- Acetylene carbonylation over Ni-containing catalysts: Role of surface structure and active site distribution
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Heterogenization of homogeneous catalyst for acetylene carbonylation was carried out by preparing a series of Ni-modified catalysts (Ni-ZSM-5, Ni-IM-5 and Ni-MCM-41). Several important properties of the heterogeneous catalysts were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES), XPS, XRD, N2 adsorption, pyridine-FTIR, SEM and TGA. Moreover, we used various activity criteria to dissipate perturbing factors, when we focused on the influence of surface structure and active site distribution. The result that Ni-IM-5 had the greatest TOFNi = 5107 g acrylic acid per g Ni per h showed that the surface structure of samples did not influence the catalyst performance significantly. In addition, the highest ratio of nickel sites/acid sites in Ni-MCM-41 represented the best active site distribution. Thus, Ni-MCM-41 has the highest TOFcat = 70.6 g acrylic acid per g cat. per h. Furthermore, stability testing of the catalysts showed the Ni-MCM-41 could be used four times, while others only twice.
- Xie, Hao,Lin, Tiejun,Shi, Li,Meng, Xuan
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- A unique nickel-base nitrogen-oxygen bidentate ligand catalyst for carbonylation of acetylene to acrylic acid
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A nickel-base nitrogen-oxygen bidentate ligand catalyst was prepared in-situ via the complexation method. Our results show that the ligand with nickel can form a chelate catalyst possessing a ring structure, which exhibits good catalytic performance in the carbonylation reaction of acetylene to acrylic acid (AA). Furthermore, we discovered that, under our optimized conditions, when 8-hydroxyquinoline (HQ) is used as the ligand [c(Ni(OAc)2·4H2O) = 15 × 10?6 mol L?1, n(HQ):n(Ni(OAc)2·4H2O) = 1:1, V(H2O) = 7 mL], 70.1% conversion of acetylene and 92.4% the selectivity of AA is achieved at 200 °C with 8.0 MPa pressure for 30 min. Compared to traditional acetylene carbonylation catalysts and nickel-base phosphine ligand homogeneous complex catalysts, our catalytic system has unique advantages, including no copper, no halogen and no carbon deposition generated during the reaction process. It displays high selectivity and no corrosion of equipment, suggesting that this catalytic system possesses future industrial applications.
- Cui, Long,Yang, Xiangui,Zeng, Yi,Chen, Yuntang,Wang, Gongying
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- Ni-exchanged Y-zeolite: An efficient heterogeneous catalyst for acetylene hydrocarboxylation
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A series of Ni-modified Y-zeolites with varying Ni loading in the presence of cupric salt as promoter were studied for acetylene hydrocarboxylation performed in a batch reactor. The catalysts were characterized by elemental analysis, H2-TPR, XRD, NH3-TPD, pyridine-FTIR, SEM, TG-DTG and Raman. It was found that the catalytic activity showed a pronounced dependence on the supports, metal introduction method, promoters and reaction conditions. The nickel species present as charge compensation cations in the zeolite framework constitute the active sites, and the acid sites help to promote the performance of carbonylation. Moreover, two types of coke were observed, and the remarkable reusability of NiY is attributable to the location of the coke outside the zeolite crystals. High catalytic performance was obtained over a NiY(7.0) catalyst with 62 gacrylic acid/(g cat. · h) of yield at 235 °C, 3.6 MPa of initial total pressure and 0.8 mM/l of cupric bromide within 40 min of reaction time. This is the most effective heterogeneous system for synthesizing acrylic acid by carbonylation of acetylene to date.
- Lin, Tie Jun,Meng, Xuan,Shi, Li
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- Exploring the multifunctionality and accessibility of vanadosilicates to produce acrylic acid in one-pot glycerol oxydehydration
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Acrylic acid is one of the most attractive products directly produced from glycerol, and many efforts are still made to thoroughly understand the role of different catalytic sites in the reaction. In this work, we prepared Al-free vanadosilicates presenting structures analog to ferrierite and ITQ-6 zeolites (2D and 3D structures). The materials were efficient in catalyzing the one-pot conversion of glycerol to acrylic acid. The different vanadium species in the catalysts had specific roles in each step of the reaction. By exposing samples to humid conditions, dissociative adsorption of water produced hydroxylated sites (O3V-OH-Si) that acted as extrinsic Br?nsted acid sites. The deprotonation energy of these sites was estimated by DFT calculations and found to be close to deprotonation energy of intrinsic Br?nsted acidity of aluminosilicates with the same zeolitic structure, indicating the ability of the active site to dehydrate glycerol to acrolein. The formation of these sites seems to effectively block potential Lewis acidity of the vanadosilicates since acetol, a dehydration side product, was not formed. Spectroscopic data showed changes in oxidation states of vanadium in these sites after the reaction, presenting V5+ and V4+ states, indicating the activity of these sites on the oxidation step during oxidation of acrolein to acrylic acid. By decreasing vanadium content during synthesis, delamination to ITQ-6 was more effective, increasing accessibility and, consequently, the productivity of sites.
- Jones, Christopher W.,Lopez-Castillo, Alejandro,Martins, Leandro,Vieira, Luiz H.
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- COMPETITION BETWEEN DECARBOXYLATION AND ISOMERIZATION IN THE C3H5O2(1+) ENERGY SURFACE. JUSTIFICATION OF THE EXPERIMENTAL RESULTS BY MOLECULAR ORBITAL CALCULATIONS ON THE SOLVATED IONS
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In contrast with recent molecular orbital calculations on the decarboxylation of O-protonated 2-oxetanone, this experimental work indicates that no decarboxylation of this cation occurs in sulphuric acid solution up to 150 deg C, but instead a clean isomerization to protonated acrylic acid takes place.Parallel theoretical work shows that the gas-phase model is too crude to account successfully for the experimental facts obtained in acidic media.However, the latter are well reproduced when the effect of the solvent is taken into account.The present findings do not necessarily invalidate the reaction mechanism currently accepted to explain the rate enhancement and change of stereochemistry accompanying the decarboxylation of 3,4-disubstituted 2-oxetanones under acid catalysis.
- Rajadell, Fernando,Planelles, Josep,Tomas, Francisco,Asensio, Gregorio,Miranda, Miguel A.,Sabater, Maria J.
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- Facile sub-/supercritical water synthesis of nanoflake MoVTeNbO:X-mixed metal oxides without post-heat treatment and their catalytic performance
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A fast and simple sub-/supercritical water synthesis method is presented in this work in which MoVTeNbOx-mixed metal oxides with various phase compositions and morphologies could be synthesized without post-heat treatment. It was demonstrated that the system temperature for synthesis had a significant influence on the physico-chemical properties of MoVTeNbOx. Higher temperatures were beneficial for the formation of a mixed crystalline phase containing TeVO4, Te3Mo2V2O17, Mo4O11 and TeO2, which are very different from the crystalline phases of conventional Mo-V-Te-Nb-mixed metal oxides. While at lower temperatures, Mo4O11 was replaced by Te. At high temperature, the as-prepared samples presented distinct nanoflake morphologies with an average size of 10-60 nm in width and exhibited excellent catalytic performances in the selective oxidation of propylene to acrylic acid. It is illustrated that the large specific surface area, presence of Mo4O11 and superficial Mo6+ and Te4+ ions are responsible for the high propylene conversion, while suitable acidic sites and superficial Nb5+ ions improved the selectivity to acrylic acid. This journal is
- Deng, Luyao,Fan, Yaoxin,Li, Shuangming,Liu, Yongwei,Lu, Zixuan,Yan, Yunong,Yu, Sansan,Zhang, Zhe
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- How important is the (001) plane of M1 for selective oxidation of propane to acrylic acid?
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The role of the (001) crystallographic plane of the M1 phase of MoVTeNb mixed-oxide catalysts in selective oxidation of propane to acrylic acid was addressed by investigating a phase-pure M1 material preferentially exposing this surface. A model catalyst was prepared by complete silylation of M1, followed by breakage of the SiO2-covered needles. Using this approach, the reactivity of the M1 (001) surface was investigated by combining a microreactor study of propane oxidation with high-sensitivity low-energy ion scattering (HS-LEIS). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to study the shape and microstructure of the model system and verify the surface exposure of the model catalyst. The specific rate of formation of acrylic acid on the model catalyst was found to be similar to that on the phase-pure M1 reference material, indicating that the (001) plane of the M1 crystal structure did not have better catalytic properties compared with the lateral surface of M1 needles in propane oxidation.
- Celaya Sanfiz,Hansen,Sakthivel,Trunschke,Schloegl,Knoester,Brongersma,Looi,Hamid
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- The regional hydrolysis of ethyl acrylate to acrylic acid in the rat nasal cavity
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Cytotoxicity is primarily limited to the olfactory epithelium of the dorsal meatus region of the nasal cavity of rodents following inhalation exposure to acrylic monomers. To investigate the biochemical basis for this effect, three regions of the Fischer F344N rat nasal cavity were evaluated for carboxylesterase activity for the representative acrylic ester, ethyl acrylate. Prior studies have indicated that the rodent olfactory epithelium is sensitive to the cytotoxic effects of short chain organic acids. In this study, no regional difference in carboxylesterase activity was observed between sensitive and non-sensitive regions of olfactory epithelium. Respiratory epithelium (resistant to cytotoxicity) was found to have a much lower rate of carboxylesterase activity than olfactory epithelium. These results suggest that the regional distribution of cytotoxicity observed in the rat nasal cavity at high concentrations of inhaled acrylic monomers may be due in part to the amount of released organic acid following deposition. However, the observation of the same esterase activity in sensitive and nonsensitive olfactory regions suggests that nasal air flow patterns and regional deposition may also be critical factors.
- Frederick, Clay B.,Udinsky, John R.,Finch, Lavorgie
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- Pd@Zn-MOF-74: Restricting a Guest Molecule by the Open-Metal Site in a Metal-Organic Framework for Selective Semihydrogenation
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In this work, we found that the open-metal site in a metal-organic framework (MOF) can be used to enhance such selectivity. Hydrogenation of phenylacetylene over such a catalyst enables ultrahigh styrene selectivity of 92% at full conversion with a turnover frequency of 98.1 h-1. The origin of ultrahigh selectivity, as unveiled by density functional theory calculation, is due to a coordination interaction between the open Zn(II) site and the C≡C bond of phenylacetylene.
- Wu, Hui Qiong,Huang, Ling,Li, Jian Qiang,Zheng, An Min,Tao, Yuan,Yang, Li Xiao,Yin, Wen Hui,Luo, Feng
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- Kinetics of osmium(VIII) catalyzed oxidation of allyl alcohol by potassium bromate in aqueous acidic medium-autocatalysis in catalysis
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The kinetics of oxidation of allyl alcohol with potassium bromate in the presence of osmium(VIII) catalyst in aqueous acid medium has been studied under varying conditions. The active species of oxidant and catalyst in the reaction were understood to be Bro3- and H2OsO5, respectively. The autocatalysis exhibited by one of the products, that is, Br-, was attributed to complex formation between bromide and osmium(VIII). A composite scheme and rate law were possible. Some reaction constants involved in the mechanism have been evaluated.
- Desai,Halligudi,Nandibewoor
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- Immobilization of rhodococcus AJ270 and use of entrapped biocatalyst for the production of acrylic acid
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Rhodococcus AJ270 is adsorbed by Dowex 1 at 15.4 mg dry weight per g resin with maximum amidase specific activity observed at lower loadings. Bacteria form a monolayer on the resin surface, and adsorption is complete within 2 min. AJ270 can be entrapped in agar and agarose gels (optimum loading: 20 mg dry weight bacteria per cm3 gel). Adsorption and entrapment improve amidase thermal stability 3-4 fold, and entrapment shifts the pH optimum from 8 to 7. Adsorbed and free bacteria show similar values for Km and Vmax, but entrapped bacteria have higher Km values. Compared with bacteria adsorbed to Dowex, the activity per cm3 of matrix of agar-entrapped AJ270 is eight-fold higher. In stirred-tank reactors, exposure to acrylic acid reduces the amidase activity of the biocatalyst in the hydrolysis of acrylamide. In column reactors, entrapped AJ270 suffers little reduction in amidase activity against 0.25 M acrylamide over 22 h continuous operation.
- Colby, John,Snell, David,Black, Gary W.
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- Surfactant-assisted synthesis of Mo-V mixed oxide catalysts for upgraded one-step conversion of glycerol to acrylic acid
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The catalytic properties of Mo-V mixed oxides hydrothermally synthetized in the presence of ionic surfactants (SDS and CTAB) were investigated in the gas-phase oxidative dehydration of glycerol. The presence of surfactants promoted a change in morphology of MoV2O8 phase, directing to formation of rod-shaped crystals, and, consequently, an increase in macroporosity of materials, generated by intercrystallite spaces, when compared to a reference sample. Rod-like morphology stabilized the MoV2O8 mixed oxide phase during glycerol conversion, avoiding migration of vanadium from crystalline to amorphous phase, like observed in the reference sample, favoring the dynamic of reduction/reoxidation of vanadium and, consequently contributing to an increase in efficiency and stability of the catalyst. Both SDS and CTAB catalysts presented higher productivity of acrylic acid and good catalytic stability, with no coke formation and considerable decrease in COX evolution during 6 h of reaction. SDS presented the best catalytic results with 100% of conversion, 57% of acrylic acid selectivity and 36% of COX selectivity.
- Rasteiro, Letícia F.,Vieira, Luiz H.,Santilli, Celso V.,Martins, Leandro
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- Kinetic study of specific base catalyzed hydrolysis of ethyl acrylate in water-ethanol binary system
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Kinetic study of hydroxide anion catalyzed hydrolysis of ethyl acrylate has been carried in ethanol-water (10-50% v/v) binary systems at the temperature range 30 ± 0.1, 35 ± 0.1, 40 ± 0.1, and 45 ± 0.1 C. Calculated specific rate constant values decreases with increasing proportion of ethanol at all temperatures. The observed retardation of a base catalyzed hydrolysis reaction is explained on the basis of fact that the formation of polarized transition state is disfavored with increase in % of ethanol. The relation between the change in dielectric constant due to variation in binary mixtures and change in specific rate constant are explained on the basis of electrostatic and non electrostatic contributions of solvent mixtures. The variation of ΔG*, ΔH*, ΔS with solvent composition and the specific effect of water on the reaction rate kinetics are also discussed.
- Sharma, Sangita,Ramani, Jayesh,Bhalodia, Jasmin,Vyas, Bijal
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- Enhancement of acrylic acid yields in propane and propylene oxidation by selective P Doping of MoV(Nb)TeO-based M1 and M2 catalysts
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The selective doping of M1 and M2 phases for the selective oxidation of propane and propylene to acrylic acid (AA) was investigated. A series of catalytic materials for the oxidation of propane were prepared with the general precursor composition Mo1V0.31-Te0.37Nb xPyOn. A first solution was prepared by dissolving ammonium heptamolybdate, ammonium vanadate, and telluric acid in water at 60°C. This solution was allowed to cool to room temperature. A second solution was prepared by dissolving niobic acid in oxalic acid at 60°C. The appropriate amount of the first solution, second solution, and phosphoric acid were mixed and then dried by rotary evaporation. Each catalyst was tested at four different space velocities, starting with the highest, at several reaction temperatures starting at the lowest temperature. Doping of crystalline M1 and M2 phases with P in selective oxidation of propane or propylene enhances significantly the desired AA yields at commercially relevant high hydrocarbon conversions.
- Grasselli,Lugmair,Volpe Jr.,Andersson,Burrington
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- Bi4Cu0.2V1.8O11-δ based electrolyte membrane reactor for selective oxidation of propane to acrylic acid
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An electrochemical membrane reactor using Bi4Cu0.2V1.8O11-δ as a solid electrolyte membrane was employed to investigate the selective oxidation of propane to acrylic acid over a MoV0.3Te0.17Nb0.12O catalyst. By applying an external current to the membrane reactor, the ionic oxygen was pumped to the surface of the MoV0.3Te0.17Nb0.12O catalyst, which exhibited higher conversion of propane and selectivity to acrylic acid than that in the fixed-bed reactor. The results indicate that the enhancement of catalytic performance in the membrane reactor is mainly due to the presence of the lattice oxygen, which has been proved to be necessary for the formation of acrylic acid. Thus, the Au/Bi4Cu0.2V1.8O11-δ/Au/MoVTeNbO membrane reactor achieved a higher conversion of propane (42%) and selectivity to acrylic acid (79.6%) at 380 °C with a 0.6 A current.
- Wang, Jibo,Ji, Baofeng,Chu, Wenling,Zhan, Shijing,Lin, Liwu,Yang, Weishen
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- V-Zr-P oxide catalysts for highly selective oxidation of propane to acrylic acid
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V-Zr-P oxide catalysts have been prepared and exhibited high selectivity in the oxidation of propane to acrylic acid.
- Han, Yi-Fan,Wang, Huai-Ming,Cheng, Hua,Deng, Jing-Fa
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- The multiple benefits of glycerol conversion to acrolein and acrylic acid catalyzed by vanadium oxides supported on micro-mesoporous MFI zeolites
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The ZSM-5 zeolite (MFI structure, Si/Al?=?40) was treated using NaOH and either oxalic acid or HCl to obtain hierarchical materials with different characteristics, followed by impregnation with vanadium oxides (V2O5) to generate redox-active sites. The impact of the multiple treatments on the efficiency and stability of the catalysts in the conversion of glycerol to acrolein and acrylic acid was investigated and correlated with catalyst porosity, acidity, and chemical composition. The treated and impregnated V2O5 catalysts were subjected to XRD, 27Al NMR, nitrogen physisorption, TPD-NH3, TG, and UV–Vis analyses, in order to associate the properties of the catalysts with their activities. The studies showed that the catalytic performance of the materials depended on the acidic and textural properties of the zeolites, which influenced both the dispersion of V2O5 and its interaction with the acid sites of the supporting zeolites. All the catalysts provided conversion values exceeding 65%, even after 6?h on glycerol stream. The distribution of products strongly reflected the effects of pore formation, acid treatment with oxalic acid or HCl, and the presence of vanadium oxide. The effects of these modifications resulted in higher selectivity to acrolein and acrylic acid, a reduced rate of coke accumulation in the zeolite, and a longer catalyst lifetime.
- Possato, Luiz G.,Chaves, Thiago F.,Cassinelli, Wellington H.,Pulcinelli, Sandra H.,Santilli, Celso V.,Martins, Leandro
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- Oxidation of Propane to Acrylic Acid on V2O5-P2O5-based Catalysts
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V2O5-P2O5-based oxides, especially V2O5-P2O5-TeO2, are effective catalysts for the partial oxidation of propane to acrylic acid using gaseous oxygen as an oxidant; a yield of 9 molpercent was reached.
- Ai, Mamoru
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- Highly Selective Synthesis of Acrylic Acid from Lactide in the Liquid Phase
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A new reaction system for the highly selective, hydrobromic acid catalyzed conversion of lactide into acrylic acid under mild conditions is reported. The applied liquid reaction system consists of a temperature-stable bromide-containing ionic liquid and 2-bromopropionic acid as a source of dry HBr, with no volatile organic solvent being used. This allows for the in situ removal of the formed acrylic acid, leading to an unmatched acrylic acid selectivity of over 72 % at full lactide conversion. Accounting for leftover reaction intermediates on the way to acrylic acid, which could be recycled in an elaborate continuous process, the proposed reaction system shows potential for acrylic acid yields well above 85 % in the liquid phase. This opens new avenues for the effective conversion of biogenic lactic acid (e.g., obtained by fermentation from starch) to acrylic acid. The resulting bio-acrylic acid is a highly attractive product for, for example, the diaper industry, where we expect consumers to be especially sensitive to aspects of sustainability.
- Nagengast, Jens,Hahn, Simon,Taccardi, Nicola,Kehrer, Matthias,Kadar, Julian,Collias, Dimitris,Dziezok, Peter,Wasserscheid, Peter,Albert, Jakob
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- Hydrothermal synthesis of Mo-V mixed oxides possessing several crystalline phases and their performance in the catalytic oxydehydration of glycerol to acrylic acid
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The one-step oxydehydration of glycerol to acrylic acid over molybdenum and vanadium mixed oxides was investigated. The Mo-V oxide catalysts were prepared by a simple hydrothermal method under different synthesis and calcination atmospheres and were characterized by in situ XRD, TPD-NH3, N2 adsorption/desorption, X-ray absorption near vanadium K-edge spectroscopy and thermogravimetry. The catalytic performance of the samples at different temperatures (290, 320 and 350 °C) and under different gas flow compositions (20% O2 in N2, 100% O2, or 100% N2) revealed that the arrangement of the crystallographic structures of the active phases directly influenced the catalytic performance. It was found that the catalysts heat-treated in oxidizing atmosphere gave superior catalytic results comparing with the catalysts heat-treated in inert atmosphere due to the equilibrium between the crystalline phases MoVO5 and Mo4.65V0.35O14 that contains V+4 and V+5. Catalytic oxydehydration at 320 °C under a flow of 100% O2 gave the best performance, achieving selectivity of 33.5% towards acrylic acid and 100% conversion of glycerol.
- Rasteiro, Letícia F.,Vieira, Luiz H.,Possato, Luiz G.,Pulcinelli, Sandra H.,Santilli, Celso V.,Martins, Leandro
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- Hierarchical NaY Zeolites for Lactic Acid Dehydration to Acrylic Acid
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The industrial viability of heterogeneous catalysts for the gas-phase conversion of lactic acid to acrylic acid will strongly depend on their selectivity and durability. Here, we initially screened various aluminum-rich zeolites confirming that NaY is the most efficient catalyst for this reaction. This material was modified by sequential dealumination and alkaline treatment attaining a solid featuring a hierarchical distribution of micro- and mesopores, reduced Lewis acidity, and increased basicity owing to the presence of well-dispersed sodium ions interacting with external siloxy groups, as evidenced by in-depth characterization. These properties were crucial for determining higher selectivity (75 %) and minimizing the activity loss in a 6 h run. Remarkably, the catalyst gained in selectivity and stability upon reuse in consecutive cycles. This was ascribed to the depletion of the stronger basic sites and the clustering of sodium into oxidic particles upon the intermediate calcination.
- Lari, Giacomo M.,Puértolas, Bego?a,Frei, Matthias S.,Mondelli, Cecilia,Pérez-Ramírez, Javier
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- Selective dehydrosulfurization of 3-mercaptopropionic acid to acrylic acid on silicalite catalyst
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Dehydrosulfurization of 3-mercaptopropionic acid has been investigated in a fixed bed reactor using a silicalite catalyst in order to recover the hydrocarbon core. Under reductive conditions, acrylic acid was formed in high yield at 350 °C and atmospheric pressure as the desired product along the toxic H2S, whereas, carrying out the reaction in the presence of air, safer dihydrogenpolysulfides resulted as the co-product.
- Pina, Cristina Della,Falletta, Ermelinda,Rossi, Michele
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- A recyclable heterogeneous-homogeneous-heterogeneous NiO/AlOOH catalysis system for hydrocarboxylation of acetylene to acrylic acid
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Concerns about the high-valued utilization of coal- A nd natural gas-based acetylene has provided particular impetus for exploration of acrylic acid (AA) production via one-step hydrocarboxylation reaction. Motivated by simple recovery, recycling and reuse of the catalyst, we report a high-performance NiO/AlOOH catalyst with AA space-time-yield of 412 gAA gcat.-1 h-1, obtainable by a simple incipient wetness impregnation method. Detailed kinetic and controlled experiments confirmed that nickel species on such a solid catalyst provide a heterogeneous-homogeneous-heterogeneous catalytic cycle where the chelates formed between CO and leached nickel act as the active species. The thorough recovery of leached nickel species improves the catalyst stability greatly. These preliminary findings indicate further prospects for new heterogeneous catalyst design in traditional homogeneous catalytic systems.
- Li, Yakun,Yan, Lifang,Zhang, Qiaofei,Yan, Binhang,Cheng, Yi
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- Nickel oxide-silica core-shell catalyst for acetylene hydroxycarbonylation
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Acrylic acid and its ester derivatives are important chemicals utilized to synthesize numerous end products. Acrylic acid is industrially produced via propylene oxidation. We report in this study a nickel oxide-silica core-shell catalyst (NiO@SiO2) for acetylene hydroxycarbonylation as an alternative way to synthesize acrylic acid. NiO@SiO2 catalyst provided the higher turnover frequency and yield than commercial nickel oxide catalyst on acetylene hydroxycarbonylation. The carbon monoxide/acetylene ratio influenced more significantly to initial reaction rate than final acrylic acid yield. The silica shell protected the nickel oxide from sintering during reaction, however, the catalyst was deactivated by coke formation, attributed to acetylene decomposition.
- Choi, Hong Sub,Park, Ji Hoon,Bae, Jong Wook,Lee, Jin Hee,Chang, Tae Sun
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- Novel Mo-V Oxide Catalysts with Nanospheres as Templates for the Selective Oxidation of Acrolein to Acrylic Acid
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Abstract: Novel Mo-V-PMMA and Mo-V-PS catalysts are prepared by addition of hard polymethyl methacrylate (PMMA) and polystyrene (PS) nanospheres into Mo/V compounds in the preparation process, respectively. The catalytic tests in selective oxidation of acrolein reveal that Mo-V-PMMA catalyst shows very high acrolein conversion (99.1%) and the yield of acrylic acid (90.7%). The BET, DLS, SAXS, XRD, XPS, H2-TPR and NH3-TPD measurements reveal that the addition of PMMA and PS nanospheres causes the obvious changes of porous structure, crystal phases composition and chemical properties of catalysts. These differences between Mo-V-PMMA and Mo-V-PS catalysts are attributed to the totally different “real” nano–environment during heat treatment in the high–concentration component mixture. PS nanospheres are in a state of adhesion or agglomeration or not uniformly distributed in the active component solution, while PMMA nanospheres with much better hydrophilicity and monodispersed state promote Mo and V ions more easily and uniformly dispersed in the mixture. Graphic abstract: Novel Mo-V catalysts are prepared by addition of hard polymethyl methacrylate (PMMA) and polystyrene (PS) nanospheres into Mo/V mixture. Obvious changes of porous structure, crystal phases and chemical properties of catalysts are caused by the nanospheres introduction, showing very high acrolein conversion (99.1%) and the yield of acrylic acid (90.7%) in selective oxidation of acrolein.[Figure not available: see fulltext.].
- Wang, Weihua,Xu, Wenjie,Song, Weilin,Yang, Bin,Li, Li,Guo, Xuhong,Wu, Lianghua,Liu, Hongxing
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p. 2326 - 2338
(2021/01/11)
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- Parahydrogen-Induced Polarization Relayed via Proton Exchange
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The hyperpolarization of nuclear spins is a game-changing technology that enables hitherto inaccessible applications for magnetic resonance in chemistry and biomedicine. Despite significant advances and discoveries in the past, however, the quest to establish efficient and effective hyperpolarization methods continues. Here, we describe a new method that combines the advantages of direct parahydrogenation, high polarization (P), fast reaction, and low cost with the broad applicability of polarization transfer via proton exchange. We identified the system propargyl alcohol + pH2 → allyl alcohol to yield 1H polarization in excess of P ≈ 13% by using only 50% enriched pH2 at a pressure of ≈1 bar. The polarization was then successfully relayed via proton exchange from allyl alcohol to various target molecules. The polarizations of water and alcohols (as target molecules) approached P ≈ 1% even at high molar concentrations of 100 mM. Lactate, glucose, and pyruvic acid were also polarized, but to a lesser extent. Several potential improvements of the methodology are discussed. Thus, the parahydrogen-induced hyperpolarization relayed via proton exchange (PHIP-X) is a promising approach to polarize numerous molecules which participate in proton exchange and support new applications for magnetic resonance.
- Them, Kolja,Ellermann, Frowin,Pravdivtsev, Andrey N.,Salnikov, Oleg G.,Skovpin, Ivan V.,Koptyug, Igor V.,Herges, Rainer,H?vener, Jan-Bernd
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supporting information
p. 13694 - 13700
(2021/09/07)
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- Cu(II)-Based Ionic Liquid Supported on SBA-15 Nanoparticles Catalyst for the Oxidation of Various Alcohols into Carboxylic Acids in the Presence of CO2
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In this paper, we have produced carboxylic acids by the oxidation of various alcohols in the presence of CO2 using SBA-15/IL supported Cu(II) (SBA-15/IL/Cu(II)) as nanocatalyst. The obtained products showed to have excellent yields by taking into account of SBA-15/IL/Cu(II) nanocatalyst. In addition, the analysis of EDX, SEM, TGA, TEM, XPS, and FT-IR showed the heterogeneous structure of SBA-15/IL/Cu (II) catalyst. It is determined that, after using SBA-15 excess, the catalytic stability of the system was enhanced. Moreover, hot filtration provided a full vision in the heterogeneous catalyst nature. The recycling as well as reuse of the catalyst were studied in cases of coupling reactions many times. Moreover, we have studied the mechanism of the coupling reactions. Graphic Abstract: [Figure not available: see fulltext.]
- Chen, Yanwu,Hou, Dejian,Lin, Litian,Peng, Qi,Sadeghzadeh, Seyed Mohsen
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- METHOD FOR MANUFACTURING A NUMBER OF REACTION TUBES FOR PRODUCING (METH)ACRYLIC ACID
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The present invention relates to a method for producing a plurality of reaction tubes for acrylic acid production. A method for manufacturing a plurality of reaction tubes is provided to minimize pressure difference between a plurality of reaction tubes.
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Paragraph 0176-0201
(2021/03/09)
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- Mo–V–O nanocrystals synthesized in the confined space of a mesoporous carbon
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Ternary Mo–V oxide nanocrystals (Nano-MoVO) were hydrothermally synthesized in the confined space of a mesoporous carbon template and tested in the oxidative dehydrogenation (ODH) of ethane and propane. The synthesized nanocrystals are approximately 60 nm in length, 20 nm in diameter on average, and possess a structure resembling orthorhombic MoVO (Orth-MoVO) as indicated by spectroscopic and microscopy characterization. The Nano-MoVO catalyst has a 5-fold higher mesopore volume and a 4-fold larger external surface area than an Orth-MoVO synthesized by a conventional method (Orth-MoVO) as characterized through N2 adsorption analysis. Nano-MoVO shows similar activation energy in the ODH of ethane compared with other conventional MoVO catalysts. However, Nano-MoVO exhibits significantly higher propane/ethane activation rate ratio and higher propene selectivity even in the absence of elements such as Te and Nb that suppress overoxidation of propane-derived species to COx. The results suggest the benefits of the nanocrystalline morphology to limit overoxidation.
- Mukai, Shin R.,Obunai, Ryo,Ogino, Isao,Tamura, Keisuke,Ueda, Wataru
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- Confined alkali metal ions in two-dimensional aluminum phosphate promoted activity for the condensation of lactic acid to 2,3-pentanedione
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The sustainable production of 2,3-pentanedione from bio-lactic acid was investigated over alkali metal ion-intercalated laminar aluminum phosphate. The confined alkali metal ion through the adjacent layers of aluminum phosphate offered excellent stability for the condensation of lactic acid to 2,3-pentanedione at least 80 h on stream, remaining constant at 55% conversion of lactic acid as well as around 80% of 2,3-pentanedione selectivity. The intercalated alkali metal ions can efficiently stabilize the enol intermediate, promoting the activity of lactic acid condensation. Besides, it can also prevent the occurrence of a layered stack of aluminum phosphate, providing an excellent mass transfer space for molecular diffusion, which is demonstrated by the calculation of the relation between molecular mean free paths for lactic acid and 2,3-pentanedione and the interlamellar spacing of aluminum phosphate. As a result, the alkali metal ion-intercalated laminar aluminum phosphate exhibited excellent performance for the condensation of lactic acid to 2,3-pentanedione at 270 °C, achieving 90% of lactic acid conversion and 80% of selectivity towards 2,3-pentanedione.
- Dai, Yunsheng,Li, Xinli,Tang, Congming,Yang, Chenglong,Zhang, Ju
-
supporting information
p. 13806 - 13813
(2021/08/16)
-
- METHOD FOR PREPARING ACRYLIC ACID AND METHYL ACRYLATE
-
The present invention provides a method for preparing acrylic acid and methyl acrylate. The method comprises passing the feed gas containing dimethoxymethane and carbon monoxide through a solid acid catalyst to generate acrylic acid and methyl acrylate with a high conversion rate and selectivity at a reaction temperature in a range from 180 to 400 and a reaction pressure in a range from 0.1 MPa to 15.0 MPa, the mass space velocity of dimethoxymethane in the feed gas is in a range from 0.05 h?1 to 10.0 h?1, and the volume percentage of dimethoxymethane in the feed gas is in a range from 0.1% to 95%.
- -
-
Paragraph 0076-0081
(2021/04/23)
-
- β(L)-Bi2Mo2O9: A new, highly active and selective, mild oxidation bismuth molybdate catalyst
-
A new bismuth molybdate, obtained by means of microwave-assisted hydrothermal synthesis, is described by the chemical formula: β(L)-Bi2Mo2O9, in accordance with its low crystallization temperature and transition to β-Bi2Mo2O9 at 532 °C. Its structure, solved ab initio using powder diffraction data, crystallizes in the monoclinic system (space group P21/c), with a = 8.11413(5), b = 8.54445(5), c = 13.43623(6) ?, and β = 123.5085(2)°. This phase has been tested as a catalyst for the oxidation of propene. It appears to be highly stable on stream, with a specific rate of propene conversion comparable to that of α-Bi2Mo3O12 and a slightly higher selectivity to acrolein. A possible active site for the abstraction of the first hydrogen from propene has been identified, by analogy with that proposed for α-Bi2Mo3O12 and seems to correspond to a molybdenyl Mo = O oxygen that is weakly coordinated to a neighboring Bi cation.
- Aouine, M.,Elka?m, E.,Guillou, N.,Le, T. M. N.,Millet, J. M. M.
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-
- ISOTOPES OF ALPHA KETOGLUTARATE AND RELATED COMPOUNDS AND THEIR USE IN HYPERPOLARIZED IMAGING
-
A compound of the Formula I or a pharmaceutically acceptable salt thereof, wherein R1, Ca, Cb, Cd, and n are the same as described in the specification. Disclosed is a method of diagnosing or monitoring a patient suffering from cancer, the method comprising: administering a pharmaceutical composition comprising an effective amount of an active agent, wherein the active agent is the compound of Formula I, a pharmaceutically acceptable salt of any of the foregoing thereof, or a combination thereof, together with a pharmaceutically acceptable carrier to the patient; and diagnosing or monitoring the patient by hyperpolarized 13C-MRI. Also disclosed is a method of synthesizing 1-13C- 5-12C-diacid.
- -
-
Paragraph 0156
(2021/07/24)
-
- Expanding the repertoire of nitrilases with broad substrate specificity and high substrate tolerance for biocatalytic applications
-
Enzymatic conversion of nitriles to carboxylic acids by nitrilases has gained significance in the green synthesis of several pharmaceutical precursors and fine chemicals. Although nitrilases from several sources have been characterized, there exists a scope for identifying broad spectrum nitrilases exhibiting higher substrate tolerance and better thermostability to develop industrially relevant biocatalytic processes. Through genome mining, we have identified nine novel nitrilase sequences from bacteria and evaluated their activity on a broad spectrum of 23 industrially relevant nitrile substrates. Nitrilases from Zobellia galactanivorans, Achromobacter insolitus and Cupriavidus necator were highly active on varying classes of nitriles and applied as whole cell biocatalysts in lab scale processes. Z. galactanivorans nitrilase could convert 4-cyanopyridine to achieve yields of 1.79 M isonicotinic acid within 3 h via fed-batch substrate addition. The nitrilase from A. insolitus could hydrolyze 630 mM iminodiacetonitrile at a fast rate, effecting 86 % conversion to iminodiacetic acid within 1 h. The arylaliphatic nitrilase from C. necator catalysed enantioselective hydrolysis of 740 mM mandelonitrile to (R)-mandelic acid in 4 h. Significantly high product yields suggest that these enzymes would be promising additions to the suite of nitrilases for upscale biocatalytic application.
- Rayavarapu, Pratima,Shah, Shikha,Sunder, Avinash Vellore,Wangikar, Pramod P.
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p. 289 - 296
(2020/05/18)
-
- Highly efficient oxidation of alcohols to carboxylic acids using a polyoxometalate-supported chromium(iii) catalyst and CO2
-
Direct catalytic oxidation of alcohols to carboxylic acids is very attractive, but economical catalysis systems have not yet been well established. Here, we show that a pure inorganic ligand-supported chromium compound, (NH4)3[CrMo6O18(OH)6] (simplified as CrMo6), could be used to effectively promote this type of reaction in the presence of CO2. In almost all cases, oxidation of various alcohols (aromatic and aliphatic) could be achieved under mild conditions, and the corresponding carboxylic acids can be achieved in high yield. The chromium catalyst 1 can be reused several times with little loss of activity. Mechanism study and control reactions demonstrate that the acidification proceeds via the key oxidative immediate of aldehydes.
- Han, Sheng,Wang, Ying,Wei, Yongge,Wu, Zhikang,Yu, Han
-
p. 3150 - 3154
(2020/06/19)
-
- Macrolactam Synthesis via Ring-Closing Alkene-Alkene Cross-Coupling Reactions
-
Reported herein is a practical method for macrolactam synthesis via a Rh(III)-catalyzed ring closing alkene-alkene cross-coupling reaction. The reaction proceeded via a Rh-catalyzed alkenyl sp2 C-H activation process, which allows access to macrocyclic molecules of different ring sizes. Macrolactams containing a conjugated diene framework could be easily prepared in high chemoselectivities and Z,E stereoselectivities.
- Goh, Jeffrey,Loh, Teck-Peng,Maraswami, Manikantha
-
supporting information
p. 9724 - 9728
(2020/12/21)
-
- FIXED-BED MULTITUBULAR REACTOR METHOD FOR PRODUCING (METH)ACRYLIC ACID USING THE SAME
-
The present invention relates to a fixed-bed multitubular reactor and a method for producing (meth)acrylic acid using the same. According to the present invention, provided is a fixed-bed multitubular reactor for producing (meth)acrylic acid, which facilitates the replacement of a catalyst to improve productivity.COPYRIGHT KIPO 2020
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Paragraph 0145-0184
(2020/08/20)
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- Catalyst for dehydration of glycerin, preparation method thereof, and production method of acrolein using the catalyst
-
The present disclosure relates to a catalyst for dehydration of glycerin, a preparation method thereof, and a production method of acrolein using the catalyst. Particularly, the catalyst according to an embodiment of the present disclosure is used in a dehydration reaction of glycerin to exhibit high catalytic activity, a high yield, and high selectivity to acrolein and acrylic acid, and has a longer lifetime compared to the conventional catalysts due to a characteristic that coke carbon cannot be easily deposited on the surface of the catalyst.
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-
Page/Page column 13-18
(2020/03/14)
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- Investigation of the acrolein oxidation on heteropolyacid catalysts by transient response methods
-
Acrylic and methacrylic acid are industrially produced via the partial oxidation of their corresponding aldehydes, namely acrolein and methacrolein. Different catalysts are used for these tasks: mixed-oxides based on Mo, V and W for the acrolein oxidation, and heteropolyacids based on Mo, V and P for the methacrolein oxidation, since the respective other catalyst has a poor performance. To generate a deeper knowledge of the catalytic mechanism, especially of the different properties of the catalysts, the heteropolyacid catalyzed acrolein oxidation was investigated and the results were compared to the mixed-oxide catalyzed acrolein oxidation. Stationary kinetic measurements and isotopic exchange experiments, such as 18O2-SSITKA H218O-SSITKA, D2O-SSITKA as well as the exchange of acrolein by its perdeuterated isotopologue, were performed. These studies provided details of the reaction mechanisms and showed many similarities but also critical differences between mixed-oxide and heteropolyacid catalysts.
- Albert, Barbara,Drochner, Alfons,Etzold, Bastian,Gora, Niklas,Heid, Maurice,Knoche, Stefan,Ohlig, Dominik,Steffan, J?rg,Vogel, Herbert
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p. 5231 - 5244
(2020/11/07)
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- METHOD FOR PREPARING LOW-GRADE UNSATURATED FATTY ACID ESTER
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Provided is a method for preparing a lower unsaturated fatty acid ester, which comprises carrying out an aldol condensation reaction between dimethoxymethane (DMM) and a lower acid or ester with a molecular formula of R1—CH2—COO—R2 on an acidic molecular sieve catalyst in an inert atmosphere to obtain a lower unsaturated fatty acid or ester(CH2═C(R1)—COO—R2), wherein R1 and R2 are groups each independently selected from the group consisting of H- and C1-C4 saturated alkyl group.
- -
-
Paragraph 0050-0057
(2020/03/09)
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- Aldol condensation of acetic acid and formaldehyde to acrylic acid over a hydrothermally treated silica gel-supported B-P-V-W oxide
-
Supported on silica B-P-V-W-Ox catalysts of the aldol condensation process, subjected to hydrothermal treatment (HTT), were synthesized and characterized. It was found that HTT of silica has a significant effect on catalyst texture, namely specific surface area, pore size. These properties affect the distribution of the active phase on the support surface. It was suggested that this is the reason of change in acid-base characteristics of the catalysts. It was observed that HTT at 100?150 °C leads to increase in surface, available for the reagents, ability to sorb acetic acid, decrease of acidity, improving catalytic activity and selectivity. It had been demonstrated that HTT allows to increase acrylic acid yield up to 67.6 % which is 10 % higher compared to that for catalyst supported on initial silica. The HTT of silica support before the active phase deposition is suggested as a cheap and efficient way to improve catalytic performance of B-P-V-W-Ox/SiO2 catalysts.
- Khalameida, S.,Khyzhun, O.,Kubitska, I.,Nebesnyi, R.,Pavliuk, A.,Pikh, Z.,Sydorchuk, V.,Voronchak, T.
-
-
- Sustainable production of pyruvic acid: Oxidative dehydrogenation of lactic acid over the FeMoO/P catalyst
-
Fe-Mo bimetallic oxide catalysts doped with elemental P (FeMoO/P) were synthesized using a hydrothermal method, followed by calcination in air. The resultant catalysts were used to catalyze the oxidative dehydrogenation of lactic acid to pyruvic acid using air as an oxidant. UV-Vis characterization revealed that Fe2O3 was highly dispersed on the surface of MoO3 for the FeMoO/P sample due to the enhanced band gap energy. The FeMoO/P sample showed distinct diffraction lines of MoO3, while the diffraction of the typical (011) line slightly shifted to a higher 2 theta value. This indicated the incorporation of Fe3+ into the MoO3 lattice, forming a surface substituted Fe-Ox-Mo solid solution. Furthermore, the other characterization techniques such as XPS and H2-TPR disclosed a strong interaction between Fe2O3 and MoO3 by binding energy shift and reducible peak change, respectively. The enhanced oxidizability of Fe species is responsible for the activation of the α-OH group in the lactic acid molecule, transferring hydrogen to the adjacent FeOx site to achieve a crucial step for the oxidative dehydrogenation of lactic acid. For comparison, the Fe-Mo bimetallic oxide catalyst offered far better activity than its corresponding monometallic oxide/physically mixed oxide due to the increasing oxidizability of FeMoO/P by electron transfer between Fe and Mo species. On-line analysis of the tail gas revealed that no hydrogen was detected, precluding direct dehydrogenation of lactic acid to form pyruvic acid during the catalytic reaction. Furthermore, the experimental results in the absence of O2, replaced by N2, showed that a small amount of pyruvic acid formed, and it gradually decreased with time on stream, demonstrating lattice oxygen as an active species for the oxidative dehydrogenation of lactic acid. Encouragingly, the oxidative dehydrogenation reaction of lactic acid over the FeMoO/P catalyst proceeded efficiently at around 60 h on stream and with an excellent selectivity (>70%).
- Yin, Chunyu,Li, Xinli,Chen, Zhi,Peng, Yanli,Wei, Song,Tang, Congming,Zou, Weixin,Dong, Lin
-
supporting information
p. 5884 - 5894
(2020/04/27)
-
- Features of the Thermolysis of Li, Na, and Cd Maleates
-
Abstract: Processes of the multi-stage decomposition of maleic acid and Li, Na, and Cd maleates in an inert atmosphere are studied via thermal analysis with synchronous analysis of the composition of the released gases. Reaction mechanisms are proposed according to the data on the mass loss stages determined via thermal analysis, gaseous products, and the final solid decomposition products. It is shown that when heated to 700°C, Li and Na carbonates incorporated into the porous carbon matrix are the final products. Above 350°C, cadmium is reduced from oxide to metal and evaporates to form a porous carbon residue as the only product of thermolysis. All carbon products are X-ray amorphous. Maleic acid decomposes completely into gaseous products in the range of 133–239°C. The maleate ion is more stable in the structure of lithium maleate than in free maleic acid, and Na and Cd cations reduce its stability.
- Avdin, V. V.,Merzlov, S. V.,Nayfert, S. A.,Polozov, M. A.,Polozova, V. V.,Sakthi Dharan, C. P.,Taskaev, S. V.,Zherebtsov, D. A.
-
p. 1311 - 1318
(2020/07/21)
-
- Byproducts formed During Thiol-Acrylate Reactions Promoted by Nucleophilic Aprotic Amines: Persistent or Reactive?
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The nucleophile-initiated mechanism of thiol-Michael reactions naturally leads to the formation of undesired nucleophile byproducts. Three aza-Michael compounds representing nucleophile byproducts of thiol-acrylate reactions initiated by 4-dimethylaminopyridine (DMAP), 1-methylimidazole (MIM), and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) have been synthesized and their reactivity in the presence of thiolate has been investigated. Spectroscopic analysis shows that each nucleophile byproduct reacts with thiolate to produce a desired thiol-acrylate product along with liberated aprotic amines DMAP, MIM, or DBU, thus demonstrating that these byproducts are reactive rather than persistent. Density functional theoretical computations support experimental observations and predict that a β-elimination mechanism is favored for converting each nucleophile byproduct into a desired thiol-acrylate product, though an SN2 process can be competitive (i. e. within 2.5 kcal/mol) in less polar solvents.
- Drogkaris, Vasileios,Northrop, Brian H.
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p. 2466 - 2474
(2020/12/03)
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- PROCESS FOR THE PRODUCTION OF METHYL ACRYLATE FROM METHYL LACTATE
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The present invention is directed to a process for the production of methyl acrylate wherein methyl lactate is contacted with a ZSM-5 catalyst in the presence of methanol. It was found that the presence of methanol is essential to obtain a selective process with a high yield. With the process according to the invention methyl acrylate may be obtained as the major product of the reaction, especially if methanol is used as solvent instead of water, while acrylic acid is detected in minor quantity (usually below 10C%, but often below 5 C%). Methanol may be used as the sole solvent in the process, but preferably also a small amount of water is present in the solvent. In one aspect of the invention, between 1 and 25 wt% of water, based on the total amount of solvent is present.
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-
Page/Page column 17
(2019/07/04)
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- Acrylonitrile Derivatives from Epoxide and Carbon Monoxide Reagents
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The present invention is directed to reactor systems and processes for producing acrylonitrile and acrylonitrile derivatives. In preferred embodiments of the present invention, the processes comprise the following steps: introducing an epoxide reagent and carbon monoxide reagent to at least one reaction vessel through at least one feed stream inlet; contacting the epoxide reagent and carbon monoxide reagent with a carbonylation catalyst to produce a beta-lactone intermediate; polymerizing the beta-lactone intermediate with an initiator in the presence of a metal cation to produce a polylactone product; heating the polylactone product under thermolysis conditions to produce an organic acid product; optionally esterifying the organic acid product to produce one or more ester products; and reacting the organic acid product and/or ester product with an ammonia reagent under ammoxidation conditions to produce an acrylonitrile product.
- -
-
Paragraph 0256-0260
(2019/01/15)
-
- SYNTHESIS METHOD OF α,β-UNSATURATED CARBOXYLIC ACID
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PROBLEM TO BE SOLVED: To provide a synthesis method of α,β-unsaturated carboxylic acid capable of improving a generation amount of the α,β-unsaturated carboxylic acid. SOLUTION: A synthetic method of α,β-unsaturated carboxylic acid, which includes to form a metal lactone compound having a specific structure as an intermediate body by reacting alkene and carbon dioxide with a transition metal complex under the presence of Lewis acid and a base to form a metal lactone compound having a specific structure as an intermediate body and to act the Lewis acid and base on the metal lactone compound, the relationship between the acid dissociation constant of the base (pKa1) of a conjugate acid of the base and the acid dissociation constant (pKa2) of the α,β-unsaturated carboxylic acid is pKa1pKa2. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPO&INPIT
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-
Paragraph 0061; 0067-0074
(2019/11/16)
-
- XANES study of the dynamic states of V-based oxide catalysts under partial oxidation reaction conditions
-
A XANES study under reaction conditions has been performed with two different V-based catalytic systems, Mo-V-Nb-Te-O and V-Sb-O. For this study, an alumina-supported nanoscaled bulk catalyst has been used. In all cases XANES determined the average vanadium oxidation state during reaction. XANES also demonstrated that the nanosized phases are more dynamic, and able to participate in the redox catalytic cycle without significant changes either in their structure or in the overall vanadium oxidation state. Such a stability is also apparent under oxidizing conditions.
- Guerrero-Pérez,López-Medina,Rojas-Garcia,Ba?ares
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p. 210 - 215
(2018/01/01)
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- PREPARING METHODE OF ACRYLIC ACID
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The present invention relates to a method for preparing acrylic acid comprising the following steps: (step 1) extracting 3-hydroxypropionic acid included in a fermented liquid using an organic solvent including an amine-based extraction agent and an alcohol-based extraction agent; (step 2) adding acid to the organic solvent extract in the step 1; and (step 3) distilling the organic solvent extract in the step 2 under reduced pressure and recovering acrylic acid. According to the present invention, acrylic acid with high purity and high yield can be manufactured from an organic acid fermented liquid with low concentration of 3-hydroxypropionic acid.COPYRIGHT KIPO 2020
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Paragraph 0042-0044
(2019/10/29)
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- Influence of the structure of trigonal Mo-V-M3rd oxides (M3rd?=?-, Fe, Cu, W) on catalytic performances in selective oxidations of ethane, acrolein, and allyl alcohol
-
Crystalline “MoVO”, “MoVCuO”, “MoVFeO” and “MoVWO” catalysts with a trigonal symmetry were successfully synthesized and characterized. The influence of the as-obtained structures on catalytic performances in selective oxidation reactions was investigated. MoVFeO and MoVCuO accomodated Fe and Cu species inside heptagonal channels, while W in MoVWO was incorporated in pentagonal {Mo6O21}6? units. Whereas MoVO and MoVWO showed catalytic activity in the selective oxidation of ethane and acrolein, MoVFeO and MoVCuO performed very poorly in the same reaction, suggesting that the presence of empty heptagonal channels is related to ethane and acrolein activations. In the selective oxidation of allyl alcohol, substantial amounts of acrolein (formed by oxidative dehydrogenation) and propanal (formed by isomerization) were formed as primary products over MoVO and MoVWO, whereas MoVFeO and MoVCuO preferentially promoted the formation of acrolein. It was found that the local crystal structure around the heptagonal channel was related with a modification of the reaction pathway for the selective oxidation of allyl alcohol. Due to the prevention of isomerization over MoVFeO, a high acrylic acid yield of 83.1% from allyl alcohol was achieved at 350 °C over this sample.
- Ishikawa, Satoshi,Murayama, Toru,Katryniok, Benjamin,Dumeignil, Franck,Araque, Marcia,Heyte, Svetlana,Paul, Sébastien,Yamada,Iwazaki, Mizuki,Noda, Nagisa,Ueda, Wataru
-
-
- Precisely phase-modulated VPO catalysts with enhanced inter-phase conjunction for acrylic acid production through the condensation of acetic acid and formaldehyde
-
A type of precisely phase-modulated vanadium phosphorus oxides (VPOs)was fabricated for the first time by quantitatively mixing the pure phase of γ-VOPO4, δ-VOPO4, and (VO)2P2O7 in certain ratios through a mechanical milling approach. The resulting materials were used as catalysts for very efficient condensation of acetic acid and formaldehyde to acrylic acid as well as methyl acrylate. The modulated dual phase VPO catalyst outperforms the single-phase counterpart, and by optimizing the reaction conditions especially the contact time, we can further considerably enhance the catalyst performance. Over an optimized catalyst of δ-VOPO4/γ-VOPO4 (w/w, 3/1), the (AA + MA)yield of 84.2% with the equivalent (AA + MA)formation rate of 1.71 mmol·g?1·h?1 or the (AA + MA)yield of 41.8% with the equivalent (AA + MA)formation rate of 4.25 mmol·g?1·h?1 is achievable at 360 °C on the formaldehyde input basis. This sort of catalyst is rather durable within a period of 110 h, and fully recovered by simple air-treatment at the reaction temperature. Due to the enhanced conjunction at the interface of two phases, the surface property of phase-modulated catalyst such as the P-O bond length and surface acidity is notably modified/enhanced, accounting for the promising catalytic performance.
- Liu, Jun,Wang, Pengcheng,Feng, Yina,Xu, Zhijia,Feng, Xinzhen,Ji, Weijie,Au, Chak-Tong
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p. 171 - 182
(2019/05/14)
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- Method for synthesizing acyclicacrylic acid from glycerinum
-
The invention relates to a method for synthesizing acyclicacrylic acid from glycerinum, aims to solve the problem of low acyclicacrylic acid yield in a process for synthesizing the acyclicacrylic acidfrom the glycerinum in the prior art. The method comprises the following steps: making a raw material containing glycerinum and a raw material containing oxygen be in contact with a catalyst; dehydrating the glycerinum to generate acrolein; further oxidizing the acrolein into the acyclicacrylic acid. The catalyst is prepared from a carrier and an active component, wherein the active component isselected from at least one of Ru, Os and Ag. By adopting the technical scheme, the technical problem is solved well. The method can be applied to the industrial production for the synthesis of the acyclicacrylic acid from the glycerinum.
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-
Paragraph 0112; 0113
(2019/02/19)
-
- PREPARATION METHOD OF ACRYLIC ACID FROM LACTIDE BY USING ION EXCHANGE RESIN
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The present invention relates to a method for manufacturing acrylic acid by dehydration of lactide derived from a biomass using a strongly acidic cation exchange resin. An object of the present invention is to provide the method for manufacturing acrylic acid, which is a high moisture absorbent raw material, in an environmentally friendly manner at a high yield and a high selectivity by using the strongly acidic cation exchange resin.COPYRIGHT KIPO 2019
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-
Paragraph 0051-0054; 0060; 0066; 0072; 0078; 0084
(2019/10/10)
-
- PREPARATION METHOD OF ACRYLIC ACID FROM LACTIDE BY USING ION EXCHANGE RESIN
-
The present invention provides a method for manufacturing acrylic acid from a dehydration reaction of lactide derived from biomass using two or more strongly acidic cation exchange resins, for example, a strong acid cation exchange resin having a particle
- -
-
Paragraph 0048-0054
(2019/10/11)
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- A synthetic acrylic acid (by machine translation)
-
The invention relates to a method for synthesis of acrylic acid, the method first methyl imidazole and bromine decane NaY molecular sieve is introduced into the cage by in-situ synthesis of the ionic liquid, further introduced into the organic acid, preparation NaY molecular sieve supported acid functionalization of the ionic liquid, and finally Pd2 + , N, P ligand sequentially introduced to the molecular sieve of the supercage in, in-situ form a palladium complex, NaY molecular sieve supported by acid functionalized ion liquid arrowhead phosphine ligand complex catalyst, then the catalyst under the action of acetylene carbonyl compound to acrylic acid. Through this method, the stability of catalyst is greatly enhanced, acetylene conversion can be up to 99% or more, acrylic acid yield can reach 98% or more, the catalyst can be repeatedly 10 times, can still be 98% of the yield of acrylic acid. (by machine translation)
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Paragraph 0022-0076
(2019/04/17)
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- An efficient and durable hierarchically porous KLA/TiPO catalyst for vapor phase condensation of lactic acid to 2,3-pentanedione
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Sustainable production of 2,3-pentanedione from bio-lactic acid via a vapor condensation reaction over KLA/TiPO (KLA: potassium lactate) was investigated in this work. A KNO3 precursor supported on the surface of TiPO was in situ converted to basic sites in a KLA/TiPO catalyst. KLA together with Ti4+(Lewis acidic site) make up the acid-base pairs in the KLA/TiPO catalyst, resulting in excellent activity for the condensation of lactic acid to 2,3-pentanedione. The loading amount of KNO3 was shown to have an important influence on the catalytic performance, since the acid-base properties of the catalysts were found to vary with the addition of KNO3. Reaction conditions such as lactic acid feed flow rate and lactic acid concentration were also discussed. Both lactic acid conversion and 2,3-pentanedione selectivity increased with elevated lactic acid feed flow rates, indicating the existence of an external diffusion resistance of the lactic acid reactant during the catalytic reactions. However, the lactic acid feed flow rate increased to 1.0 mL h?1 (corresponding to LA liquid hourly space velocity (LHSV) = 2.6 H?1), and the external diffusion resistance was efficiently eliminated. Enhancing the LA concentration improved the selectivity of 2,3-pentanedione, suggesting that the reaction order of the lactic acid molecule for lactic acid conversion to 2,3-pentanedione is higher than the other side reactions. Encouragingly, in retaining 30-45% of the lactic acid conversion, the condensation reaction with a 2,3-pentanedione selectivity of around 73% proceeded efficiently for at least 116 h on stream. The long-term stability of the present catalyst was found to be related to its hierarchical pores, which ameliorated the mass transfer effect of the reactant and product, except for the appropriate acid-base properties for lactic acid condensation to 2,3-pentanedione.
- Zhang, Ju,Li, Xinli,Pang, Jun,Zou, Weixin,Tang, Congming,Dong, Lin
-
supporting information
p. 5972 - 5979
(2019/04/17)
-
- ΑII-(V1-xWx)OPO4 catalysts for the selective oxidation of n-butane to maleic anhydride
-
The vanadyl pyrophosphate (VPP) based catalyst is unique in converting n-butane selectively (60–70%) into maleic anhydride (MAN), whereas a MAN selectivity of 20% may be regarded as high for structurally different catalyst systems. We present novel vanadium phosphorus oxides and mixed metal phosphate solid solutions tested for n-butane oxidation to MAN with a selectivity of >30%. The majority of the catalysts were prepared by solution combustion synthesis. (V1-xWx)OPO4 with αII structure was found to be more active and selective in the oxidation of n-butane compared to β-VOPO4. By adjusting the tungsten content the oxidation state of vanadium in (V1-xWx)OPO4 can be tuned between 4.74 and 4.99, which is regarded as a key factor for MAN production. All catalysts were structurally stable, but the specific surface area increased during the reaction, as detected by X-ray diffraction and N2 physisorption, respectively. (V1-xMox)OPO4 was also stable, but the MAN selectivity was lower compared to β-VOPO4. Low conversions result from the low surface area of the screening samples, however, could be overcome by advanced synthesis protocols.
- Schulz,Roy,Wittich,d'Alnoncourt, R. Naumann,Linke,Strempel,Frank,Glaum,Rosowski
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p. 113 - 119
(2018/06/20)
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- CeO2 promoting allyl alcohol synthesis from glycerol direct conversion over MoFe/CeO2 oxide catalysts: morphology and particle sizes dependent
-
MoFe-N, MoFe/c–CeO2, MoFe/p1–CeO2, and MoFe/p2–CeO2 (where N, c, and p stand for non-supported, nanocube, and nanoparticle) oxide catalysts were designed for gas-glycerol direct catalytic conversion into allyl alcohol. The catalysts also were characterized by XRD, TEM, BET, H2-TPR, and NH3-TPD. Mo–Fe oxides were highly dispersed on the surface of c-CeO2 and p-CeO2 supports, different with the MoFe-N consist of crystalline Fe2(MoO4)3 and Fe2O3 crystalline phase. The support effect and special natural property of CeO2 significantly improve the allyl alcohol selectivity from gas-glycerol over MoFe/CeO2. The p-CeO2 with low particle sizes and crystalline degree was superior to high-crystalline nanocube c-CeO2 to promote its interaction with the MoFe oxide active components, and improve the surface acid site concentration and reducibility of MoFe/CeO2 as well as catalytic activity and stability for allyl alcohol synthesis from gas-glycerol without any extra hydrogen donors. Over the MoFe/p2–CeO2, the glycerol conversion reached 97.1%, and the selectivity of allyl alcohol, enthanal, propanoic acid, and acrylic acid were 23.3%, 8.6%, 12.6%, and 7.8%, respectively, yielding allyl alcohol of 22.6%.
- Lan, Hai,Zeng, Jia,Zhang, Biao,Jiang, Yi
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p. 1565 - 1580
(2018/12/13)
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- Transient directing ligand-and solvent-controlled C-H/C-H cross-coupling/quaternization cyclization/dequaternization of benzaldehydes with thiophenes
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Rh(iii)-Catalyzed oxidative C-H/C-H cross-coupling between benzaldehydes and thiophenes has been accomplished for the first time. In such reactions, transient directing ligands (TDLs) can not only promote ortho-C-H activation, but can also control the chemoselectivity through a suitable combination of different solvents.
- Sun, Denan,Du, Jiping,Fang, Hao,Lan, Jingbo,Wu, Di,You, Jingsong
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supporting information
p. 7518 - 7521
(2019/07/04)
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- Selenium-Modified Microgels as Bio-Inspired Oxidation Catalysts
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Active colloidal catalysts inspired by glutathione peroxidase (GPx) were synthesized by integration of catalytically active selenium (Se) moieties into aqueous microgels. A diselenide crosslinker (Se X-linker) was successfully synthesized and incorporated into microgels through precipitation polymerization, along with the conventional crosslinker N,N′-methylenebis(acrylamide) (BIS). Diselenide bonds within the microgels were cleaved through oxidation by H2O2 and converted to seleninic acid whilst maintaining the intact microgel microstructure. Through this approach catalytically active microgels with variable amounts of seleninic acid were synthesized. Remarkably, the microgels exhibited higher catalytic activity and selectivity at low reaction temperatures than the molecular Se catalyst in a model oxidation reaction of acrolein to acrylic acid and methyl acrylate.
- Tan, Kok H.,Xu, Wenjing,Stefka, Simon,Demco, Dan E.,Kharandiuk, Tetiana,Ivasiv, Volodymyr,Nebesnyi, Roman,Petrovskii, Vladislav S.,Potemkin, Igor I.,Pich, Andrij
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supporting information
p. 9791 - 9796
(2019/06/24)
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- Diazotization of S-Sulfonyl-cysteines
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We report the preparation of enantiomerically enriched β-thio-α-hydroxy and α-chloro carboxylic acid and ester building blocks by diazotization of S-sulfonyl-cysteines. The thiosulfonate protecting group demonstrated resistance to oxidation and attenuation of sulfur's nucleophilicity by the anomeric effect. The key transformation was optimized by a 22 factorial design of experiment, highlighting the unique reactivity of cysteine derivatives in comparison with aliphatic amino acids.
- Mear, Sarah Jane,Jamison, Timothy F.
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p. 15001 - 15007
(2019/11/05)
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- A glyceric acid preparation of acrylic acid (by machine translation)
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The invention relates to a method for the preparation of acrylic acid from the glyceric acid, under mild reaction conditions in the first, in water, hydrogen iodic acid and glyceric acid generating 3 - iodoproptonic acid; then, extracting with an organic solvent 3 - iodoproptonic acid; finally, alkaline catalyst or Lewis acid catalyst catalytic 3 - iodoproptonic acid generating cancels out the reaction producing the acrylic. The reactant used in the present invention is cheap, source green; the reaction time is short, high-efficiency energy-saving; very few [...], 1st step product 3 - iodoproptonic acid productive rate can reach 99%, 2nd step product acrylic acid yield can be up to 99%. This method for the method of extraction separation 1st step product, and directly used for 2nd step two-phase system cancels out the reaction. This method high selectivity, after treatment is simple, easy industrialization; reaction system is simple, low in cost, has very important application value. (by machine translation)
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Paragraph 0020; 0021; 0031; 0033; 0035; 0037; 0039; 0041
(2019/01/07)
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- CATALYSTS FOR MAKING ACRYLIC ACID FROM LACTIC ACID OR ITS DERIVATIVES IN LIQUID PHASE
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Catalysts for the dehydration of lactic acid, lactic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof in liquid phase comprising an ionic liquid (IL) and an acid are provided.
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Page/Page column 67
(2018/02/28)
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- METHOD OF MAKING ACRYLIC ACID FROM LACTIC ACID OR LACTIDE USING MOLTEN SALT CATALYSTS
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A method of making acrylic acid in liquid phase by contacting a feed stream containing lactic acid, lactide, or mixtures thereof with a molten salt catalyst comprising a protic ionic liquid (PIL), which contains a bromide anion (Br-), is provided.
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Page/Page column 24-32; 54
(2018/09/28)
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- HETEROGENEOUS CATALYST FOR PREPARING ACRYLIC ACID, AND ACRYLIC ACID PREPARATION METHOD USING SAME
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The present disclosure relates to a catalyst used in the preparation of acrylic acid and acrylic acid preparation method using the same, and more specifically, discloses a catalyst capable of enhancing selectivity of acrylic acid and a production yield of acrylic acid when preparing acrylic acid from allyl alcohol using a heterogeneous catalyst including bimetallic alloy catalyst particles of gold and another metal, and an acrylic acid preparation method using the same.
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Paragraph 0091; 0092; 0093; 0116
(2018/08/03)
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- METHOD FOR PRODUCING UNSATURATED CARBOXYLIC ACID SALT
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PROBLEM TO BE SOLVED: To provide a method for producing a useful chemical which is a carboxylate, which enables the hydrocarboxylation reaction of olefins by effectively utilizing carbon dioxide without using an expensive reducing agent. SOLUTION: There is provided a method for producing an unsaturated carboxylic acid salt which comprises: a step of reacting olefins and carbon dioxide in the presence of a transition metal complex containing at least one metal element selected from Group 6 to Group 9 to obtain a metallalactone species; a step of converting the metallalactone species into an O-carboxylate complex by β-hydrogen desorption; and a step of regenerating the transition metal complex from the O-carboxylate complex and obtaining an unsaturated carboxylic acid salt. SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
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Paragraph 0067; 0068
(2018/04/14)
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- Method for oxidizing propylene to synthesize acrylic acid
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The invention belongs to the field of acrylic acid synthesis and in particular relates to a method for oxidizing propylene to synthesize acrylic acid. The method comprises the following steps: mixingpropylene, oxygen, vapor and an inert gas according to a volume ratio of 1:(5-25):(0.1-0.5):(5-25), introducing mixed gases into a reaction device, and carrying out an oxidation reaction on the mixedgases at 0.5-1.3MPa at 320-400 DEG C; putting an oxidation catalyst into the reaction device, condensing a reaction product after the oxidation reaction is completed so as to obtain an acrylic acid solution, treating the acrylic acid solution by using an extraction process, and carrying separation, thereby obtaining the acrylic acid. The oxidation catalyst used in the method is composed of expanded graphite as a carrier and specific active components carried by the carrier, the amounts of different active components are optimized, then the catalyst has good selectivity and catalysis activity,and thus the concentration of the acrylic acid can be greatly increased.
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Paragraph 0013-0026
(2018/11/22)
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- METHOD FOR PREPARING ACRYLIC ACID FROM GLYCERIN
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The present invention relates to a method for preparing acrylic acid from glycerin. More specifically, the present invention provides a method which can improve the selectivity of acrolein by applying a specific catalyst composition and process conditions to minimize the generation of coke carbon of the catalyst, and can prepare acrylic acid with higher productivity for a longer duration of time because a dehydration reaction can be performed for a longer working period while maintaining catalyst activity at a high level during the reaction.
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Paragraph 0062; 0063; 0068; 0070; 0071
(2018/10/19)
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