- Impact of composition and structural parameters on the catalytic activity of MFI type titanosilicalites
-
Titanosilicalite of the MFI type was obtained via a hydrothermal method. Its initial and annealed at 75 °C (TS-1P(75)) and 500 °C (TS-1P(500)) forms were studied by X-ray powder diffraction (PXRD), X-ray absorption spectroscopy (XAS-method), Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), temperature-programmed ammonia desorption (TPD NH3), and pyridine adsorption (Py). The full-profile Rietveld method allowed us to observe the presence of the organic template tetrapropylammonium hydroxide (TPAOH) in the framework voids, as well as to determine the silicate module (Si/Ti = 73.5) and the distribution of Ti4+ ions over the MFI-type structure sites (Ti atoms replace Si ones in two positions: T1 and T6). The coordination numbers of titanium (CNTi = 4.6 for TS-1P and TS-1P(75), CNTi = 3.8 for TS-1P(500)) were established by the XAS-method. The catalytic activity of titanosilicalites was found in the reactions of nitrous oxide decomposition (the maximal decomposition rate is demonstrated for the TS-1P(75) sample), allyl chloride epoxidation to epichlorohydrin (the best combination of all indicators was exhibited for the TS-1P sample) and propane conversion (maximum propane conversion, and butadiene and propylene selectivity were observed in both TS-1P(75) and TS-1P(500) samples). Mechanisms for the catalytic processes are proposed. The relationship between the catalytic properties and the composition (Si/Ti), Ti4+ ion distribution over the MFI-type structure sites, the local environment of titanium ions, and the number of acid sites in the titanosilicalites are discussed.
- Bruk, Lev,Chernyshev, Vladimir,Khramov, Evgeny,Kravchenko, Galina,Kustov, Aleksander,Kustov, Leonid,Kuz'Micheva, Galina,Markova, Ekaterina,Pastukhova, Zhanna,Pirutko, Larisa
-
p. 3439 - 3451
(2022/03/14)
-
- SUPPORTED TANTALUM CATALYST FOR THE PRODUCTION OF 1,3-BUTADIENE
-
The invention relates to a process for the production of 1,3-butadiene from a feed comprising ethanol and acetaldehyde in the presence of a supported tantalum catalyst obtainable by aqueous impregnation of the support with a water-soluble tantalum precursor. Furthermore, the present invention relates to a process for the production of a supported tantalum catalyst, and the supported tantalum catalyst. Finally, the invention relates to the use of the supported tantalum catalyst for the production of 1,3-butadiene from a feed comprising ethanol and acetaldehyde to increase one or both of selectivity and yield of the reaction.
- -
-
Page/Page column 14-17
(2021/04/03)
-
- Understanding Ta as an Efficient Promoter of MgO–SiO2 Catalyst for Conversion of the Ethanol–Acetaldehyde Mixture into 1,3-Butadiene
-
In this work, Ta was firstly reported as an efficient promoter of MgO–SiO2 for the conversion of ethanol and acetaldehyde to 1,3-butadiene. The doping of Ta into MgO–SiO2 forms Ta–O–Si bonds and generates more strong Lewis acid sites, which not only promote the aldol condensation reaction but also significantly facilitate the Meerwein–Ponndorf–Verley reduction, the total conversion around 80% which drops to 65% after 24?h. In addition, the catalyst showed desirable stability in 24?h long-term stability evaluation, the selectivity remained stable at 80%. Graphic Abstract: [Figure not available: see fulltext.]
- Gao, Qiang,Jiang, Angjiong,Jiang, Haoxi,Yang, Guochao,wang, Lingtao
-
-
- Chemoenzymatic Buta-1,3-diene Synthesis from Syngas Using Biological Decarboxylative Claisen Condensation and Zeolite-Based Dehydration
-
A method for producing buta-1,3-diene (1,3-BD) by an amalgamation of chemical and biological approaches with syngas as the carbon source is proposed. Syngas is converted to the central intermediate, acetyl-CoA, by microorganisms through a tetrahydrofolate metabolism pathway. Acetyl-CoA is subsequently converted to malonyl-CoA using a carbonyl donor in the presence of a carboxylase enzyme. A decarboxylative Claisen condensation of malonyl-CoA and acetaldehyde ensues in the presence of acyltransferases to form 3-hydroxybutyryl-CoA, which is subsequently reduced by aldehyde reductase to give butane-1,3-diol (1,3-BDO). An ensuing dehydration step converts 1,3-BDO to 1,3-BD in the presence of a chemical dehydrating reagent.
- Balasubramaniam, Sivaraman,Badle, Sneh,Badgujar, Swati,Veetil, Vinod P.,Rangaswamy, Vidhya
-
p. 705 - 711
(2020/12/01)
-
- Selective production of 1,3-butadiene from 1,3-butanediol over Y2Zr2O7 catalyst
-
The vapor-phase dehydration of 1,3-butanediol (1,3-BDO) to produce 1,3-butadiene (BD) was evaluated over yttrium zirconate, which was prepared through a hydrothermal aging process. 1,3-BDO was initially dehydrated to three unsaturated alcohols, namely 3-buten-2-ol, 3-buten-1-ol, and 2-buten-1-ol, followed by the further dehydration to BD. The catalytic activity of yttrium zirconate was greatly dependent on the calcination temperature. Also, the reaction temperature was one of the important factors to produce BD efficiently. The selectivity to BD was increased with increasing reaction temperature up to 375°C, while coke formation resulted in catalyst deactivation together with by-product formation at higher temperatures. Yttrium zirconate catalyst calcined at 900°C showed a high BD yield of 95% at 375°C and 10 hr on stream.
- Matsuda, Asami,Matsumura, Yoshitaka,Sato, Satoshi,Yamada, Yasuhiro
-
p. 1651 - 1658
(2021/07/21)
-
- METHOD FOR PRERARING BUTADIENE
-
The present invention relates to a method for producing butadiene, comprising butenes, steam and oxygen (O). 2 The method according to S10, wherein the mixed gas stream comprising the inert diluent gas and inert diluent 1 gas is fed to the first reactor (step S). The catalyst of claim 1, wherein the mixed gas stream is passed through a catalytic bed containing MoBi or more selected from the group consisting of a ferritic and 1-series metal oxide catalyst in the first reactor. S20. The reaction product stream is fed into the reactor 2. The 2-series metal oxide catalyst in a MnCe-th reactor passes through a catalyst layer, and includes a step (S30) of removing the oxygen compound contained in the reaction product stream, wherein the operating temperature of the first reactor 1 150 is 250, and the operating temperature of the first reactor 550 °C is 350 °C 2.
- -
-
Paragraph 0088-0131
(2021/10/17)
-
- CATALYTIC CONVERSION OF ETHANOL TO 1-/2-BUTENES
-
Simple and economical conversion of aqueous ethanol feed streams into butenes by a single step method using transition metal oxides on a silica supports under preselected processing conditions. By directly producing a C4-rich olefin mixture from an ethanol containing stream various advantages are presented including, but not limited to, significant cost reduction in capital expenses and operational expenses.
- -
-
Paragraph 0013-0022; 0026-0046
(2021/06/11)
-
- Oxidative dehydrogenation of n-butene to buta-1,3-diene with novel iron oxide-based catalyst: Effect of iron oxide crystalline structure
-
We investigate the effect of the crystalline structure of iron oxide catalysts on oxidative dehydrogenation (ODH) of n-butene. ODH reactions of n-butene were carried out with a fixed-bed flow reactor at 450 °C under a but-1-ene (1-C4H8) or cis-but-2-ene (cis-2-C4H8)(mL/min)/O2(mL/min) flow ratio of 5/2.5. Of the various iron oxide-based catalysts (α-, β-, γ-, ε-Fe2O3, Fe3O4, ZnFe2O4), ε-Fe2O3 showed the highest ODH activity. To the best of our knowledge, ε-Fe2O3 has never been used for the ODH of n-butene. Moreover, the catalytic performance of ε-Fe2O3 was improved by adding SiO2, which is related to the maintenance of its structure and improves its redox property. A high BD selectivity of 65 % and BD yield of 18 % were then obtained for 4 h without deactivation. This catalyst can be applied to the ODH of cis-2-C4H8 and is proposed as the noble high catalytic performance catalyst for the ODH of n-butene.
- Kiyokawa, Takayasu,Ikenaga, Naoki
-
-
- Effect of Steam–Air Treatment of Alumina–Chromia Dehydrogenation Catalysts on Their Physicochemical and Catalytic Characteristics
-
The effect of calcined alumina–chromia catalyst containing 13 wt.% Cr with additions of Na+ and Zr4+ in an air–water vapor atmosphere (from 0 to 80 vol % water vapor) at 750°С and a pressure of 1 bar on the physicochemical properties of the catalyst and its activity in n-butane dehydrogenation was evaluated. The steam treatment led to a slight decrease in the specific surface area (by up to 10%), partial decomposition of Cr(VI) compounds (up to 60%), and Cr2O3 crystallization. The catalytic activity decreased with an increase in the water vapor:air ratio. Low water vapor concentration (10 vol %) favored a remarkable decrease in the amount of the coke formed (by 60%) without considerably affecting alkene yield. Thus, the introduction of water vapor into the calcination atmosphere allowed control of the Cr(VI) amount and catalyst selectivity.
- Nazimov,Klimov,Saiko,Noskov
-
p. 1283 - 1291
(2021/12/29)
-
- CATALYTIC HYDROCARBON DEHYDROGENATION
-
A catalyst for dehydrogenation of hydrocarbons includes a support including zirconium oxide and Linde type L zeolite (L-zeolite). A concentration of the zirconium oxide in the catalyst is in a range of from 0.1 weight percent (wt. %) to 20 wt. %. The catalyst includes from 5 wt. % to 15 wt. % of an alkali metal or alkaline earth metal. The catalyst includes from 0.1 wt. % to 10 wt. % of tin. The catalyst includes from 0.1 wt. % to 8 wt. % of a platinum group metal. The alkali metal or alkaline earth metal, tin, and platinum group metal are disposed on the support.
- -
-
Paragraph 0059; 0060; 0124; 0125
(2021/03/13)
-
- Pt/TS-1 catalysts: Effect of the platinum loading method on the dehydrogenation of n-butane
-
A series of catalysts in which platinum was supported on the crystalline pure titanium silicalite (TS-1) were prepared using two different loading methods, namely, an ethylene glycol (EG) reduction method and the conventional incipient wetness impregnation (IM) technique. Various characterization techniques were used to study the effect of the loading method on the physicochemical and morphological properties of the prepared catalysts. Also the effect of the platinum-loading method on the dehydrogenation of n-butane was investigated in a fixed-bed reactor. The results show that the EG method favors the formation of a more-concentrated Pt dispersion, which results in much better catalytic activities for the selective formation of butenes and butadiene (> 97 %). This phenomenon is interpreted by carrying out density functional theory (DFT) calculations with focus on the relationship between the coverage of n-butane on Pt surface and the activation barrier for the first C[sbnd]H bond cleavage.
- Shao, Mingyuan,Hu, Chaoquan,Xu, Xuebing,Song, Yang,Zhu, Qingshan
-
-
- Selective Butene Formation in Direct Ethanol-to-C3+-Olefin Valorization over Zn-Y/Beta and Single-Atom Alloy Composite Catalysts Using in Situ-Generated Hydrogen
-
The selective production of C3+olefins from renewable feedstocks, especially via C1and C2platform chemicals, is a critical challenge for obtaining economically viable low-carbon middle-distillate transportation fuels (i.e., jet and diesel). Here, we report a multifunctional catalyst system composed of Zn-Y/Beta and “single-atom” alloy (SAA) Pt-Cu/Al2O3, which selectively catalyzes ethanol-to-olefin (C3+, ETO) valorization in the absence of cofed hydrogen, forming butenes as the primary olefin products. Beta zeolites containing predominately isolated Zn and Y metal sites catalyze ethanol upgrading steps (588 K, 3.1 kPa ethanol, ambient pressure) regardless of cofed hydrogen partial pressure (0-98.3 kPa H2), forming butadiene as the primary product (60% selectivity at an 87% conversion). The Zn-Y/Beta catalyst possesses site-isolated Zn and Y Lewis acid sites (at ～7 wt % Y) and Br?nsted acidic Y sites, the latter of which have been previously uncharacterized. A secondary bed of SAA Pt-Cu/Al2O3selectively hydrogenates butadiene to butene isomers at a consistent reaction temperature using hydrogen generatedin situfrom ethanol to butadiene (ETB) conversion. This unique hydrogenation reactivity at near-stoichiometric hydrogen and butadiene partial pressures is not observed over monometallic Pt or Cu catalysts, highlighting these operating conditions as a critical SAA catalyst application area for conjugated diene selective hydrogenation at high reaction temperatures (>573 K) and low H2/diene ratios (e.g., 1:1). Single-bed steady-state selective hydrogenation rates, associated apparent hydrogen and butadiene reaction orders, and density functional theory (DFT) calculations of the Horiuti-Polanyi reaction mechanisms indicate that the unique butadiene selective hydrogenation reactivity over SAA Pt-Cu/Al2O3reflects lower hydrogen scission barriers relative to monometallic Cu surfaces and limited butene binding energies relative to monometallic Pt surfaces. DFT calculations further indicate the preferential desorption of butene isomers over SAA Pt-Cu(111) and Cu(111) surfaces, while Pt(111) surfaces favor subsequent butene hydrogenation reactions to form butane over butene desorption events. Under operating conditions without hydrogen cofeeding, this combination of Zn-Y/Beta and SAA Pt-Cu catalysts can selectively form butenes (65% butenes, 78% C3+selectivity at 94% conversion) and avoid butane formation using onlyin situ-generated hydrogen, avoiding costly hydrogen cofeeding requirements that hinder many renewable energy processes.
- Allard, Lawrence F.,Assary, Rajeev S.,Cordon, Michael J.,Krause, Theodore R.,Kropf, A. Jeremy,Li, Zhenglong,Lin, Fan,Liu, Dongxia,Miller, Jeffrey T.,Purdy, Stephen C.,Unocic, Kinga A.,Wang, Huamin,Wegener, Evan C.,Yang, Ce,Zhang, Junyan,Zhou, Mingxia
-
p. 7193 - 7209
(2021/06/30)
-
- Zeolitic catalytic conversion of alcohols to olefins
-
A catalyst composition for converting an alcohol to olefins, the catalyst composition comprising the following components: (a) beta zeolite; (b) at least one element selected from the group consisting of zinc, magnesium, calcium, strontium, sodium, and potassium; and (c) at least one element selected from the group consisting of hafnium, yttrium, zirconium, tantalum, niobium, and tin; wherein the components (b) and (c) are independently within or on a surface of said beta zeolite. The catalyst may also further include component (d), which is copper or silver. Also described herein is a method for converting an alcohol to one or more olefinic compounds, the method comprising contacting the alcohol with a catalyst at a temperature of at least 100° C. and up to 500° C. to result in the alcohol being converted to the one or more olefinic compounds.
- -
-
Page/Page column 11; 12
(2021/07/08)
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- Vapor-phase dehydration of 1,4-butanediol to 1,3-butadiene over Y2Zr2O7 catalyst
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Vapor-phase catalytic dehydration of 1,4-butanediol (1,4-BDO) was investigated over Y2O3-ZrO2 catalysts. In the dehydration, 1,3-butadiene (BD) together with 3-buten-1-ol (3B1OL), tetrahydrofuran, and propylene was produced depending on the reaction conditions. In the dehydration over Y2O3-ZrO2 catalysts with different Y contents at 325°C, Y2Zr2O7 with an equimolar ratio of Y/Zr showed high selectivity to 3B1OL, an intermediate to BD. In the dehydration at 360°C, a BD yield higher than 90% was achieved over the Y2Zr2O7 calcined at 700°C throughout 10 h. In the dehydration of 3B1OL over Y2Zr2O7, however, the catalytic activity affected by the calcination temperature is roughly proportional to the specific surface area of the sample. The highest activity of Y2Zr2O7 calcined at 700 °C for the BD formation from 1,4-BDO is explained by the trade-off relation in the activities for the first-step dehydration of 1,4-BDO to 3B1OL and for the second-step dehydration of 3B1OL to BD. The higher reactivity of 3B1OL than saturated alcohols such as 1-butanol and 2-butanol suggests that the C=C double bond of 3B1OL induces an attractive interaction to anchor the catalyst surface and promotes the dehydration. A probable mechanism for the one-step dehydration of 1,4-BDO to BD was discussed.
- Matsuda, Asami,Matsumura, Yoshitaka,Sato, Satoshi,Yamada, Yasuhiro
-
-
- Nickel-catalyzed reductive 1,3-diene formation from the cross-coupling of vinyl bromides
-
Facile construction of 1,3-dienes building upon cross-electrophile coupling of two open-chain vinyl halides is disclosed in this work, showing moderate chemoselectivities between the terminal bromoalkenes and internal vinyl bromides. The present method is mild and tolerates a range of functional groups and can be applied to the total synthesis of a tobacco fragrance solanone.
- Sha, Yunfei,Liu, Jiandong,Wang, Liang,Liang, Demin,Wu, Da,Gong, Hegui
-
supporting information
p. 4887 - 4890
(2021/06/16)
-
- Synthesis of Butadiene from Formaldehyde and Propylene on Cesium Salts of Silicotungstic Heteropoly Acid
-
Abstract: A one-stage gas-phase synthesis of butadiene from formaldehyde and propylene on silica-supported cesium salts of silicotungstic heteropoly acid was realized for the first time. The physicochemical properties of the catalysts were studied by X-ray fluorescence analysis, low-temperature nitrogen adsorption, XRD, SEM, Raman spectroscopy, and NH3–TPD. The coke deposits were studied by the TGA–DTA method. Analysis of the catalytic properties showed that an increase in the concentration of cesium atoms in CsxH4–xSiW12O40/SiO2 (x = 0–3) has a beneficial effect on the endurance of the catalyst but is accompanied by a decrease in activity and butadiene selectivity. In the case of CsH3SiW12O40/SiO2, the butadiene selectivity was 51 mol %. [Figure not available: see fulltext.]
- Dobryakova, I. V.,Ivanova, I. I.,Kasyanov, I. A.,Matveeva, О. D.,Nikiforov, A. I.,Ponomareva, О.А.,Shkuropatov, A. V.
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p. 916 - 924
(2021/08/16)
-
- Direct Evidence on the Mechanism of Methane Conversion under Non-oxidative Conditions over Iron-modified Silica: The Role of Propargyl Radicals Unveiled
-
Radical-mediated gas-phase reactions play an important role in the conversion of methane under non-oxidative conditions into olefins and aromatics over iron-modified silica catalysts. Herein, we use operando photoelectron photoion coincidence spectroscopy to disentangle the elusive C2+ radical intermediates participating in the complex gas-phase reaction network. Our experiments pinpoint different C2-C5 radical species that allow for a stepwise growth of the hydrocarbon chains. Propargyl radicals (H2C?C≡C?H) are identified as essential precursors for the formation of aromatics, which then contribute to the formation of heavier hydrocarbon products via hydrogen abstraction–acetylene addition routes (HACA mechanism). These results provide comprehensive mechanistic insights that are relevant for the development of methane valorization processes.
- ?ot, Petr,Hemberger, Patrick,Pan, Zeyou,Paunovi?, Vladimir,Puente-Urbina, Allen,van Bokhoven, Jeroen Anton
-
supporting information
p. 24002 - 24007
(2021/10/01)
-
- DEPOLYMERIZATION OF OLIGOMERS AND POLYMERS COMPRISING CYCLOBUTANE UNITS
-
Methods of polymer and/or oligomer depolymerization are described herein which, in some embodiments, enable facile polymer and/or oligomer decomposition under mild, non-energy intensive conditions. Briefly, a method of depolymerization comprises providing a reaction mixture comprising a transition metal catalyst, and a polymer or oligomer having a backbone including cyclobutane units, and decomposing the polymer or oligomer to provide diene monomer or alkene monomer.
- -
-
Paragraph 0033; 0034
(2021/08/06)
-
- Synthesis of 1,3-Butadiene from 1-Butanol on a Porous Ceramic [Fe,Cr]/γ-Al2O3(K,Ce)/α-Al2O3 Catalytic Converter
-
Abstract: —A two-stage method was developed for the synthesis of 1,3-butadiene by dehydration of 1-butanol to a mixture of butenes on γ-Al2O3 granules prepared by self-propagating high-temperature synthesis (SHS) followed by dehydrogenation of the butene fraction to 1,3-butadiene using a porous ceramic catalytic SHS converter [Fe,Cr]/γ-Al2O3(K,Ce)/α-Al2O3. The dehydration of 1-butanol to the butene mixture proceeded almost completely at ~100percent selectivity on γ-Al2O3 granules obtained by SHS at 300°C, which is 50 degrees lower than on industrial gamma-alumina granules. The use of an original hybrid catalytic membrane reactor (HCMR) with selective removal of hydrogen from the reaction zone led to a ~1.3-fold increase in the yield of 1,3-butadiene at ultrapure hydrogen extraction of up to 16 mol percent of the total amount of the hydrogen product. The catalytic activity of the system did not decrease after 20 h of experiment, in contrast to its activity in the industrial process, where catalyst regeneration is performed every 8–15 min.
- Dumeignil, F.,Fedotov, A. S.,Heyte, S.,Marinova, M.,Moiseev, I. I.,Paul, S.,Simon, P.,Tsodikov, M. V.,Uvarov, V. I.
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p. 390 - 404
(2020/07/03)
-
- Ethanol Conversion to Butadiene over Isolated Zinc and Yttrium Sites Grafted onto Dealuminated Beta Zeolite
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Zinc and Yttrium single sites were introduced into the silanol nests of dealuminated BEA zeolite to produce Zn-DeAlBEA and Y-DeAlBEA. These materials were then investigated for the conversion of ethanol to 1,3-butadiene. Zn-DeAlBEA was found to be highly active for ethanol dehydrogenation to acetaldehyde and exhibited low activity for 1,3-butadiene generation. By contrast, Y-DeAlBEA was highly active for 1,3-butadiene formation but exhibited no activity for ethanol dehydrogenation. The formation of 1,3-butadine over Y-DeAlBEA and Zn-DeAlBEA does not occur via aldol condensation of acetaldehyde but, rather, by concerted reaction of coadsorbed acetaldehyde and ethanol. The active centers for this process are Si-O-Y(OH)-O-Si or Si-O-Zn-O-Si-O groups closely associated with adjacent silanol groups. The active sites in Y-DeAlBEA are 70 times more active than the Y sites supported on silica, for which the Y site is similar to that in Y-SiO2 but which lacks adjacent hydroxyl groups, and are 7 times more active than the active sites in Zn-DeAlBEA. We propose that C-C bond coupling in Y-DeAlBEA proceeds via the reaction of coadsorbed acetaldehyde and ethanol to form crotyl alcohol and water. The dehydration of crotyl alcohol to 1,3-butadiene is facile and occurs over the mildly Br?nsted acidic Si-OH groups present in the silanol nest of DeAlBEA. The catalysts reported here are notably more active than those previously reported for both the direct conversion of ethanol to 1,3-butadiene or the formation of this product by the reaction of ethanol and acetaldehyde.
- Qi, Liang,Zhang, Yanfei,Conrad, Matthew A.,Russell, Christopher K.,Miller, Jeffrey,Bell, Alexis T.
-
supporting information
p. 14674 - 14687
(2020/10/13)
-
- Highly active and durable WO3/Al2O3catalysts for gas-phase dehydration of polyols
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Gas-phase glycerol dehydration over WO3/Al2O3catalysts was investigated. WO3loading on γ-Al2O3significantly affected the yield of acrolein and the catalyst with 20 wt% WO3loading showed the highest activity. The WO3/Al2O3catalyst with 20 wt% WO3loading showed higher activity and durability than the other supported WO3catalysts and zeolites. The number of Br?nsted acid sites and mesopores of the WO3/Al2O3catalyst did not decrease after the reaction, suggesting that glycerol has continuous access to Br?nsted acid sites inside the mesopores of WO3/Al2O3, thereby sustaining a high rate of formation of acrolein. Dehydration under O2flow further increased the durability of the WO3/Al2O3catalyst, enabling the sustainable formation of acrolein. In addition, the WO3/Al2O3catalyst with 20 wt% WO3loading showed high activity for the dehydration of various polyols to afford the corresponding products in high yield.
- Aihara, Takeshi,Asazuma, Katsuya,Miura, Hiroki,Shishido, Tetsuya
-
p. 37538 - 37544
(2020/10/19)
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- N,N,O-Coordinated tricarbonylrhenium precatalysts for the aerobic deoxydehydration of diols and polyols
-
Rhenium complexes are well known catalysts for the deoxydehydration (DODH) of vicinal diols (glycols). In this work, we report on the DODH of diols and biomass-derived polyols using L4Re(CO)3as precatalyst (L4Re(CO)3= tricarbonylrhenium 2,4-di-tert-butyl-6-(((2-(dimethylamino)ethyl)(methyl)amino)methyl)phenolate). The DODH reaction was optimized using 2 mol% of L4Re(CO)3as precatalyst and 3-octanol as both reductant and solvent under aerobic conditions, generating the active high-valent rhenium speciesin situ. Both diol and biomass-based polyol substrates could be applied in this system to form the corresponding olefins with moderate to high yield. Typical features of this aerobic DODH system include a low tendency for the isomerization of aliphatic external olefin products to internal olefins, a high butadiene selectivity in the DODH of erythritol, the preferential formation of 2-vinylfuran from sugar substrates, and an overall low precatalyst loading. Several of these features indicate the formation of an active species that is different from the species formed in DODH by rhenium-trioxo catalysts. Overall, the bench-top stable and synthetically easily accessible, low-valent NNO-rhenium complex L4Re(CO)3represents an interesting alternative to high-valent rhenium catalysts in DODH chemistry.
- Klein Gebbink, Robertus J. M.,Li, Jing,Lutz, Martin
-
p. 3782 - 3788
(2020/06/22)
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- METHOD FOR PREPARING 1,3-BUTADIENE
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One embodiment of the present application provides a method for preparing 1,3-butadiene, the method comprising the steps of: introducing a reactant containing butene and oxygen into a first reactor and performing an oxidative dehydrogenation process in the first reactor; and introducing oxygen and a first product formed through the first reactor into a second reactor connected in series with the first reactor, wherein the first product formed through the first reactor includes 1,3-butadiene, a light component, and a heavy component, and removing the heavy component from the second reactor.(AA) O2 inputCOPYRIGHT KIPO 2020
- -
-
Paragraph 0069; 0072-0075
(2020/05/15)
-
- SINGLE-STAGE METHOD OF BUTADIENE PRODUCTION
-
The invention relates to a gas-phase synthesis of butadiene from ethanol or from a mixture of ethanol and acetaldehyde. The method of production includes conversion of ethanol or a mixture of ethanol with acetaldehyde in the presence of a catalyst, wherein the reaction is carried out in the presence of a solid catalyst with a mesoporous Zr-containing zeolite having a BEA type structure and at least one metal in a zero oxidation state selected from the group: silver, copper and gold. The claimed method is suitable for carrying out the reaction under continuous flow conditions in the reactor with a fixed bed of catalyst. The invention makes possible to achieve a high yield of butadiene with high selectivity to butadiene and high stability of the catalyst.
- -
-
Paragraph 0039-0042
(2020/11/24)
-
- Catalyst for reaction for preparing 1,3-butadiene from ethanol, preparation and applications thereof
-
The invention relates to a catalyst for a reaction for preparing 1,3-butadiene from ethanol, a preparation method and applications thereof. The catalyst is an MFI type molecular sieve, which has a nanosheet layer structure, contains two transition metals X and Y and an alkaline earth metal Z, and is formed by cross growth of nanosheet layers, wherein the thickness of the nanosheet layer is 2-50 nm, the metal component X of the catalyst is one or more than two selected from transition metal elements Zn, Ni, Fe, Cu and Ag, the component Y of the catalyst is one or more than two selected from acidic or alkaline metals Zr, Y, Hf, La, Ce, Sn and Ta, and the metal elements are loaded on a molecular sieve carrier in a post-treatment manner. The invention provides a catalyst for preparing 1,3-butadiene by stably and efficiently catalyzing ethanol conversion, a preparation method and applications thereof, wherein the catalyst has obvious industrial application value in a process for preparing butadiene from ethanol.
- -
-
Paragraph 0040-0095
(2020/06/17)
-
- Dehydrogenation of 1-butene with CO2 over VOx supported catalysts
-
Butadiene (BD) is an important intermediate in chemical industry and is obtained predominantly from fossil sources. In the future new and sustainable BD sources and synthesis routes might be required to meet the rising demands for this compound. Here, the synthesis of BD from 1-butene in the presence of CO2 was studied using supported vanadium oxide as active compound. Among the tested supports SBA-15 was shown to be the most effective one and a maximum BD yield of 39 % could be achieved. The VOx/SBA-15 catalysts were characterized by complementary methods to obtain insight about the effect of catalyst synthesis and vanadium loadings on the formation of VOx surface structures as well as the catalytic performance. CO2 has a positive impact on the reaction. Coking was considered to be the main reason for the catalyst deactivation and the decreasing BD yield with increasing time on stream.
- Bartling, S.,Eckelt, R.,Iffl?nder, K.,Kreyenschulte, C.,Lund, H.,Steinfeldt, N.,Wotzka, A.
-
-
- Oxidative dehydrogenation of n-butane to butadiene catalyzed by new mesoporous mixed oxides NiO-(beta-Bi2O3)-Bi2SiO5/SBA-15 system
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NiO-beta-Bi2O3-Bi2SiO5/SBA-15 catalysts, containing 10?20 wt% Ni and 10?30 wt% Bi loaded as metal weight on mesoporous SiO2 support (SBA-15), were utilized for the oxidative dehydrogenation of n-butane to butadiene, comparing from the viewpoint of Bi oxide phase and combination balance with Ni oxide and the support. Bi2SiO5 and beta-Bi2O3 phases change depending on Ni/Bi ratio. “Reverse core-shell” structure with uniform mesoporosity catalytically active for the oxidative dehydrogenation of n-butane to butadiene was successfully synthesized with semi-dry conversion method. The shell was formed as Bi2SiO5/SBA-15 by partially dissolving an array of silanol inside SBA-15 mesopores with impregnated bismuth nitrate. The Bi2SiO5 of the shell was increased by co-impregnated nickel nitrate. The layered core faced to mesopore was formed as catalytically active NiO/beta-Bi2O3 on the shell. The degrees of formation Bi2SiO5 and beta-Bi2O3 reflected in the butadiene selectivity through changing the reducibility and dispersion properties. The catalyst with moderate loading of 20 wt% Ni and 10 wt% Bi exhibited a high advantage in the n-butane conversion: 30 % and butadiene selectivity: 49 % at 450 °C compared to the less and excess loaded catalysts. The catalytic performance of other mesoporous silica support catalysts also changed differently depending on Bi2SiO5 and beta-Bi2O3 phases.
- Aitani, A. M.,Alasiri, H.,Asaoka, S.,Tanimu, G.
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- MESOPOROUS SILICA SUPPORTED CATALYST FOR OXIDATIVE DEHYDROGENATION
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Oxidative dehydrogenation catalysts comprising bismuth and nickel oxides impregnated on mesoporous silica supports such as SBA-15 and mesoporous silica foam. Methods of preparing and characterizing the catalysts as well as processes for oxidatively dehydrogenating n-butane to butadiene using the catalysts are also described. The disclosed catalysts demonstrate higher n-butane conversion and butadiene selectivity than catalysts supported by conventional silica.
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Paragraph 0035; 0052; 0122-0127
(2020/07/07)
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- Conversion of ethanol to butadiene over mesoporous In2O3-promoted MgO-SiO2 catalysts
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Mesoporous MgO-SiO2 mixed oxide catalysts were prepared for the conversion of ethanol to 1,3-butadiene. Mesoporosity was obtained by using SBA-15 material as support for magnesia or by applying one-pot synthesis method wherein magnesia precurso
- Barthos, Róbert,Hancsók, Jen?,May, Zoltán,Novodárszki, Gyula,Szabó, Blanka,Valyon, József
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- CATALYST, DEVICE FOR MANUFACTURING CONJUGATED DIENE, AND METHOD FOR MANUFACTURING CONJUGATED DIENE
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A catalyst for synthesizing a conjugated diene from a raw material including an alcohol, which includes at least Ce and Zn as metal elements constituting the catalyst. An apparatus for producing a conjugated diene, including: a reaction tube (1) provided with the catalyst; a supply means for supplying a raw material gas containing the raw material into the reaction tube (1); and an outlet means for releasing a product from the reaction tube (1). A method for producing a conjugated diene, including contacting a raw material gas containing a raw material with the catalyst to obtain a conjugated diene. The amount of the raw material is preferably 10 to 50% by volume (in terms of gas volume) with respect to 100% by volume (in terms of gas volume) of the raw material gas.
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Paragraph 0119-0120
(2020/07/14)
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- MgO?SiO2 Catalysts for the Ethanol to Butadiene Reaction: The Effect of Lewis Acid Promoters
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MgO?SiO2 samples, having the composition of natural talc (NT), were obtained by co-precipitation (CP) and wet kneading (WK) methods. The materials were used as catalysts of the ethanol-to-1,3-butadiene reaction. ZnO, Ga2O3 and In2O3 were tested as promoters. The catalyst WK gave the highest 1,3-Butadiene (BD) yield among the non-promoted catalysts because of the high specific surface area and strong basicity. Results suggested that over the neat WK catalyst the acetaldehyde coupling to crotonaldehyde was the rate-determining process step. Formation of crotyl alcohol intermediate was substantiated to proceed by the hydrogen transfer reaction between crotonaldehyde and ethanol. The crotyl alcohol intermediate becomes dehydrated to BD or, in a disproportionation side reaction, it forms crotonaldehyde and butanol. The promoter was found to increase the surface concentration of the reactant and reaction intermediates, thereby increases the rates of conversion and BD formation. The order of promoting efficiency was Zn>In>Ga.
- Szabó, Blanka,Novodárszki, Gyula,Pászti, Zoltán,Domján, Attila,Valyon, József,Hancsók, Jen?,Barthos, Róbert
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p. 5686 - 5696
(2020/09/22)
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- Improving the synthesis of Zn-Ta-TUD-1 for the Lebedev process using the Design of Experiments methodology
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The synthesis method of a zinc-tantalum catalyst supported on three-dimensional mesoporous silica with high specific surface area was studied. Its activity in the conversion of ethanol to butadiene was optimized using the Design of Experiment approach. A Plackett-Burman screening design identified the important preparation parameters, notably the ratio of Zn to Ta. It was subsequently optimized using the Response Surface Methodology, affording a highly active catalyst.
- Pomalaza, Guillaume,Capron, Micka?l,Dumeignil, Franck
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- The influence of zinc loadings on the selectivity control of bio-ethanol transformation over MgO-SiO2 catalysts
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Catalytic transformation of ethanol has been studied over a series of MgO-SiO2 composite catalysts with different ZnO loadings. Vast differences in product selectivity are obtained by varying ZnO loadings in enabling the control over product distribution. Our results reveal that MgO-SiO2 composite catalysts with low ZnO loadings tend to show an enhanced efficiency for C[sbnd]C bond coupling and exceptionally high selectivity to 1,3-butadiene whereas the high ZnO loadings favor the formation of acetaldehyde via dehydrogenation. Thorough analysis of characterization results via XRD, BET, IR, TPD, and 29Si MAS NMR indicates that ZnO loading influences the extent of MgO and SiO2 interaction during preparation, and the surface acid-base chemistry, which were both found to correlate with the catalytic performance. This study proposes that the Mg[sbnd]O[sbnd]Si interfacial structure formed by the strong MgO and SiO2 interaction at low ZnO loadings is of prime importance for the formation of 1,3-butadiene, benefiting from the desirable properties of balanced dehydrogenation and C[sbnd]C bond coupling while excess ZnO loadings destroy the Mg[sbnd]O[sbnd]Si interfacial bonds over the MgO-SiO2 composite catalysts, which are the key structures required for C[sbnd]C bond growth.
- Liu, Shuang,Men, Yong,Song, Qiaoling,Wang, Jinguo,Wang, Xuefei,Yang, Mei
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- Properties and activity of Zn-Ta-TUD-1 in the Lebedev process
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A zinc and tantalum-containing mesoporous silica catalyst highly active and selective in the Lebedev process has been prepared using the one-pot TUD-1 methodology. Selectivity towards butadiene reached 60-70%, making Zn-Ta-TUD-1 one of the best performing catalysts in the literature. To rationalize these results and establish a structure-activity relationship, a series of similar catalysts was prepared and characterized. Nitrogen physisorption, XPS, ICP-AES, XRD, TEM, UV-vis spectroscopy, TGA NH3-TPD, H2-TPR and FT-IR techniques were used. The most active samples were found to possess a large specific surface area and highly dispersed metal oxide phase incorporated within the mesoporous silica matrix. In combination with catalytic testing, characterization also showed a direct correlation between the number of Lewis acid sites and butadiene yield, confirming the structure-activity relationship theory prevalent for the Lebedev process. Deactivation of Zn-Ta-TUD-1 was also studied using the same techniques to characterize the properties of spent catalysts. It was found that the accumulation of heavy carbonaceous species caused a reduction of specific surface area and pore size coinciding with the observed loss in activity. Nevertheless, the pores of TUD-1 were large enough to avoid total pore blockage and a high selectivity could be maintained for 72 hours.
- Pomalaza, Guillaume,Simon, Pardis,Addad, Ahmed,Capron, Micka?l,Dumeignil, Franck
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supporting information
p. 2558 - 2574
(2020/05/13)
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- METHOD AND CATALYST FOR THE PRODUCTION OF 1, 3-BUTADIENE FROM ETHANOL
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The present invention is concerned with a catalyst for the conversion of ethanol to 1,3-butadiene comprising a component A selected from the list consisting of zeolite, silicon dioxide, aluminium oxide, or any combination thereof; and a component Bcat comprising a mixed metal oxide, a catalyst precursor for the preparation of a catalyst for the conversion of ethanol to 1,3-butadiene comprising a component A selected from the list consisting of zeolite, silicon dioxide, aluminium oxide, or any combination thereof; and a component Bpre comprising a layered double hydroxide (LDH) as well as a process for the conversion of ethanol to 1,3-butadiene, in which said catalyst is used.
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Page/Page column 19; 20
(2020/08/28)
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- Detection of Steady State Multiplicity during Dimethyl Ether Conversion Catalyzed by ZnO/γ-Al2O3 Composite: Effect of Coke and Hydrogen Peroxide
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Abstract: The heterogeneous catalytic conversion of dimethyl ether (DME) to 1,3-butadiene and butylenes in the presence of a ZnO/γ-Al2O3 catalyst in a wide range of temperatures, feed space velocities, and reactant concentrations has been studied. It has been found that temperature regions of 380–420 and 440–480°C, which are conventionally designated as low-temperature and high-temperature regions, differ in the laws governing the occurrence of the process associated with the specificity of coking of the catalyst surface and a redistribution of the surface concentration of Br?nsted and Lewis acid sites. A hypothesis of a change of the catalytic process mechanism upon the transition of the reaction into the high-temperature region has been put forward and confirmed by the occurrence of a hysteresis detected in this temperature range. The effect of hydrogen peroxide on the hysteresis parameters and the steady state stability during DME conversion has been shown.
- Maksimov, A. L.,Talyshinskii, R. M.,Tret’yakov, V. F.
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p. 773 - 784
(2020/07/31)
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- New ZnCe catalyst encapsulated in SBA-15 in the production of 1,3-butadiene from ethanol
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ZnO-CeO2/SBA-15 catalysts were prepared by two kinds of solid-state grinding method and used for the production of 1,3-butadiene (1,3-BD) from ethanol. A mixture of SBA-15 (with or without organic template) and metal precursors were ground in solid-state. The obtained catalysts were characterized by TG, N2 adsorption-desorption, TEM, XRD, Py-FTIR and NH3-TPD techniques. Superior dispersion of metal oxides and more exposed acid sites were achieved on the catalyst 10Zn1Ce5-AS with the presence of organic template in SBA-15 during the solid-state grinding process. The catalytic performance was evaluated in a fixed-bed reactor and a 1,3-butadiene selectivity of as high as 45% is achieved. This is attributed to the coupling effect of Zn and Ce species in the mesopores of SBA-15, in which Zn promotes ethanol dehydrogenation and Ce enhances aldol-condensation, respectively. Additionally, solvent-free method inspires new catalyst synthesis strategy for the production of 1,3-butadiene from ethanol.
- Zhao, Yujun,Li, Sijia,Wang, Zheng,Wang, Shengnian,Wang, Shengping,Ma, Xinbin
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supporting information
p. 535 - 538
(2019/05/21)
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- New PtSn structured catalysts with ZnAl2O4 thin film for n-butane dehydrogenation reaction
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Starting from structured supports based on compact spheres coated with a thin and porous layer of ZnAl2O4, mono and bimetallic catalysts were prepared. These catalysts were applied for the n-butane dehydrogenation reaction to produce light olefins. The structured supports were synthesized by coating with: bohemite-nitrate purified method (BP) and citrate-nitrate method (C). From the characterization results, the existence of strong Pt-Sn interaction in both bimetallic catalysts with probable alloys formation was found. In the PtSn/Sp-Zn-C catalyst, where higher metallic Pt-Sn interactions were observed, most of its metallic particles have sizes between 1 and 1.5 nm, which indicates a good metallic dispersion. These properties led to a catalyst with the best catalytic behavior, thus showing high yields to butenes, and a very good stability. Moreover, the presence of a structured support improves the mass and heat transference in this reaction carried out at high temperature.
- de Miguel, Sergio,Ballarini, Adriana,Bocanegra, Sonia
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- Borane-induced ring closure reaction of oligomethylene-linked bis-allenes
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The trimethylene-linked bis-allene 3a reacts with Piers' borane [HB(C6F5)2] by a hydroboration/allylboration sequence to generate the cyclization product 5a. Its pyridine adduct was isolated and characterized by X-ray diffraction. Compound 5a undergoes a typical frustrated Lewis pair 1,2-P/B alkene addition reaction with PPh3 to give the heterobicyclic bridged olefinic zwitterionic product 9a. The tetramethylene-linked bis-allene 3b and its phenylene annulated analogue 3c react with HB(C6F5)2 to give the analogous seven-membered ring products 5b,c under mild conditions. The cyclization product 5a undergoes a series of sequential allylboration reactions with two equivalents of allene followed by ring-closure to give the four-component coupling product 12a. It undergoes FLP addition to an exo-methylene group upon treatment with PPh3. Compound 12a is oxidatively converted to the boron-free alcohol.
- Tao, Xin,?koch, Karel,Daniliuc, Constantin G.,Kehr, Gerald,Erker, Gerhard
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p. 1542 - 1548
(2020/02/25)
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- Insight in the relationship between magnetism of stoichiometric spinel ferrites and their catalytic activity
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In this work, spinel ferrites were chosen as prototype systems for oxidative dehydrogenation of 1-butene to address the long-standing issue that whether there is a correlation between catalytic and magnetic properties of magnetic catalysts. Under zero magnetic field, the conversion was the largest for NiFe2O4 (74.5 mol%) and the least for ZnFe2O4 (12.6 mol%), with no quantative relationship between magnetism and catalytic activity. In contrast, under a magnetic field of 1603 Oe, the largest and least conversion values changed to 86.6 and 13.5 mol% for MgFe2O4 and ZnFe2O4, respectively, and these values exhibited an inverse Gauss relation with initial susceptibility.
- Chen, Kezheng,Liu, Chunting,Ma, Ji
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- Single-reactor conversion of ethanol to 1-/2-butenes
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A simplified processes for producing desired chemicals such as butenes from feedstock mixtures containing ethanol. In one set of embodiments this is performed in a single step, wherein a feed containing ethanol in a gas phase is passed over an acidic metal oxide catalyst having a transition metal dispersion of at least 5% on a metal oxide support. The ethanol content of the feedstock mixture may vary from 10 to 100 percent of the feed and in those non-eat applications the ethanol feed may contain water.
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Page/Page column 9
(2020/06/03)
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- Intermetallic GaPd2 Thin Films for Selective Hydrogenation of Acetylene
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The preparation of single-phase and catalytically active GaPd2 coatings was accomplished via DC magnetron sputtering using an intermetallic sputter target. Thin and uniform layers were deposited on borosilicate glass, Si(111) and planar as well as micro-structured stainless steel foils. The specimens were examined regarding their phase composition, film morphology and microstructure. Thin films of different layer thickness were catalytically characterized in the semi-hydrogenation of acetylene, which was conducted at 473 K and a feed gas composition of 0.5 vol.percent C2H2, 5 vol.percent H2 as well as 50 vol.percent C2H4 in helium. Pre-reduction of the catalyst was found to be essential to enhance the catalytic selectivity. Sputtered GaPd2 showed a high selectivity of 73 percent for the hydrogenation to ethylene at conversion levels above 80 percent. The surface-specific activity was strongly increased to 8.97 molacetylene·(A0·h)–1 compared to bulk- or nanoscale GaPd2 (1.93 and 0.30 molacetylene·(A0·h)–1, respectively) caused by the high specific surface area of the thin films.
- Zimmermann, René R.,Siebert, Martin,Ibrahimkutty, Shyjumon,Dittmeyer, Roland,Armbrüster, Marc
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p. 1218 - 1226
(2020/06/09)
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- Conversion of ethanol to 1,3-butadiene over high-performance Mg-ZrO: X/MFI nanosheet catalysts via the two-step method
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Mg-Zr/MFI nanosheet (NS) catalysts were prepared by a wet impregnation method for ethanol conversion to 1,3-butadiene (1,3-BD) via the two-step method in a dual fixed bed reaction system. Compared with Zr catalysts loaded on MFI(micro) or commercial SiO2, 16%Zr/MFI(NS) gave the better performance, with 42.3% 1,3-BD selectivity and 60.5% total conversion of ethanol and acetaldehyde. Introducing 1.2 wt% Mg to 16%Zr/MFI(NS) improved the 1,3-BD selectivity to 54.7% at the expense of a 6% drop in the catalytic activity. Reaction conditions imposed remarkable influence on the reaction results. When the reaction was conducted at 350 °C, a WHSV of 1.44 h-1 and a 2 : 1 ratio of ethanol to acetaldehyde, the 1,3-BD selectivity reached 74.6% with 41.5% total conversion. Such high performance over 1.2%Mg-16%Zr/MFI(NS) was maintained well in a 7 day (168 h) run without deactivation. The catalysts were characterized by XRD, N2 adsorption, UV-Vis, Raman, and infra-red spectroscopy, NH3-TPD, TEM and TG. The results showed that the Zr species on MFI(NS) are well distributed with the highest dispersion as compared with the microporous MFI and SiO2 supported Zr catalysts. The Zr species preferentially occupied the silanol nests of MFI(NS) and eliminated the Br?nsted acid sites at 4 wt% Zr loading, and afforded abundant Lewis acid sites in the form of Zr(OH)(OSi)3 when the Zr loading was increased to 16 wt%. As a base site, Mg is inactive for MPVO reduction but slightly active for the aldol condensation of acetaldehyde, both of which are much inferior to that of the Lewis acid sites. The 1.2%Mg-16%Zr/MFI(NS) catalyst with hierarchical structures of meso- and micro-pores, abundant weak Lewis acid sites but nearly no Br?nsted acid sites is competent for the two-step ethanol to 1,3-BD conversion process with high activity, selectivity and stability.
- Li, Lin,Li, Xianquan,Pan, Xiaoli,Pang, Jifeng,Wang, Chan,Zhang, Tao,Zheng, Mingyuan
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p. 2852 - 2861
(2020/06/17)
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- Deoxygenation of Epoxides with Carbon Monoxide
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The use of carbon monoxide as a direct reducing agent for the deoxygenation of terminal and internal epoxides to the respective olefins is presented. This reaction is homogeneously catalyzed by a carbonyl pincer-iridium(I) complex in combination with a Lewis acid co-catalyst to achieve a pre-activation of the epoxide substrate, as well as the elimination of CO2 from a γ-2-iridabutyrolactone intermediate. Especially terminal alkyl epoxides react smoothly and without significant isomerization to the internal olefins under CO atmosphere in benzene or toluene at 80–120 °C. Detailed investigations reveal a substrate-dependent change in the mechanism for the epoxide C?O bond activation between an oxidative addition under retention of the configuration and an SN2 reaction that leads to an inversion of the configuration.
- Maulbetsch, Theo,Jürgens, Eva,Kunz, Doris
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p. 10634 - 10640
(2020/07/30)
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- Olefin reaction in the catalyst and the olefin production
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PROBLEM TO BE SOLVED: To provide a catalyst for obtaining an olefin in high selectivity with a vicinal diol as a raw material.SOLUTION: A catalyst for olefination reaction for use in a reaction to produce an olefin by a reaction of a polyol, having two adjacent carbon atoms each having a hydroxy group, with hydrogen comprises: a carrier; at least one oxide selected from the group consisting of oxides of the group 6 elements and oxides of the group 7 elements supported on the carrier; and at least one metal selected from the group consisting of silver, iridium, and gold supported on the carrier.SELECTED DRAWING: None
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Paragraph 0145-0146; 0149
(2020/10/31)
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- SHS Membrane for the Dehydrogenation of n-Butanol to Butadienes
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Abstract—: We have synthesized catalytically active membranes based on α- and γ-Al2O3 powders for the dehydration and dehydrogenation of butyl alcohol to butadiene and hydrogen. The open porosity of the samples obtained in this study is 41% in the case of α-Al2O3 and 38% in the case of γ-Al2O3. The open pore size is 4.6–5.1 μm in the α-Al2O3 material and 0.5–0.8 μm in the γ-Al2O3 material. We have implemented a hybrid, membrane–catalytic process for the dehydrogenation of butanol by combining reaction and hydrogen separation steps in a single device. It has been demonstrated that the dehydration of n-butanol on a γ-Al2O3 converter leads to the formation of a butylene fraction with a selectivity of 99.88–100% at a temperature of 300°C, which is 50°C lower than in the case of commercially available gamma-alumina granules. The dehydrogenation of butylene to butadiene on an α-Al2O3 membrane with selective hydrogen removal from the reaction zone has made it possible to raise the 1,3-butadiene output from 16.5 to 22.6 L/(h gact. comp.), with the degree of ultrapure hydrogen extraction reaching ~16%. After the experiment was run for 20 h, no decrease in the catalytic activity of the system was detected, as distinct from commercial solutions, in which a regeneration step is necessary every 8–15 min.
- Uvarov,Alymov,Loryan,Shustov,Fedotov,Tsodikov
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p. 798 - 802
(2019/09/09)
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- Method for synthesizing diene compounds based on aldehyde-ketone condensation reaction
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The invention provides a method for synthesizing diene compounds based on an aldehyde-ketone condensation reaction. The method comprises the following steps: firstly, under the action of a condensation catalyst, performing a condensation reaction on ketone compounds and aldehyde compounds to obtain condensation products; then, under the action of a reduction catalyst, performing a reduction reaction on the condensation products obtained in the previous step to obtain reduction products; under the action of a catalyst, performing a dehydration reaction on the reduction products obtained in theprevious step to obtain the diene compounds. According to the method, ketone, aldehyde as well as homologues of ketone and aldehyde which are cheap and easy to obtain can be used as raw materials forsynthesizing the diene compounds such as butadiene, piperylene as well as homologues of butadiene and piperylene, experimental conditions are mild, the operation is simple, and a large-scale synthesisprospect is achieved.
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Paragraph 0156; 0166-0168; 0205; 0211-0214
(2019/05/08)
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- METHODS OF PRODUCING 1,3-BUTADIENE FROM ETHYLENE AND SULFUR
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Methods, catalysts, and systems for the production of 1,3-butadiene from a reaction mixture including ethylene and gaseous sulfur are described.
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Paragraph 0058
(2019/03/05)
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- Catalysts for Selective Coupling of Olefins, and Methods of Making and Using Same
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The present invention relates in part to the unexpected discovery of novel complexes capable of catalyzing the selective dehydrogenative coupling of olefins. The invention further relates to the use of these complexes for the selective coupling of olefins.
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Paragraph 0160; 0166-0169
(2019/05/15)
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- CATALYST FOR OXIDATIVE DEHYDROGENATION AND METHOD OF PREPARING THE SAME
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The present invention relates to a catalyst for oxidative dehydrogenation and a method of preparing the same. More particularly, the present invention provides a catalyst for oxidative dehydrogenation allowing oxidative dehydrogenation reactivity to be secured while increasing a first pass yield, and a method of preparing the catalyst.
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Paragraph 0101-0107
(2019/07/04)
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