- Clean and Green Procedure for the Synthesis of Biodiesel from the Esterification of Free Fatty Acids and Alcohol Catalyzed by 6-O-(sulfobutyl)-Β-cyclodextrin
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The catalyst of 6-O-(sulfobutyl)-β-cyclodextrin (SB-CD) is renewable, non-toxic, environmentally benign and biocompatible, which could be used as efficient and recyclable catalyst for the synthesis of biodiesel from free long-chain fatty acids with low-chain alcohols as substrates. The reaction was accomplished at 60°C for 1.5 h, while the products were separated from the catalyst system by liquid/liquid at room temperature with good conversion of 91–98%. The catalyst can be reused for 10 times. The novel and clean procedure offers advantages including short reaction time, good conversion, operational simplicity, and environmentally benign characteristics.
- Zhang, Guangqing,He, Leqin,Yuan, Mingxia,Li, Hui,Chang, Tao,Qin, Shenjun
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- Immobilization of a thiol-functionalized ionic liquid onto HKUST-1 through thiol compounds as the chemical bridge
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A novel heterogeneous catalyst [HVIm-(CH2)3SO3H]HSO4@HKUST-1 (IL@HKUST-1), with both Lewis and Br?nsted acid sites, was developed for the esterification of oleic acid with short-chain alcohols. HKUST-1 was chemically modified with ethanedithiol, and the vinyl-containing ionic liquid was then grafted onto the carrier through thiol groups. The catalyst IL@HKUST-1 was characterized by XRD, N2 adsorption-desorption, FT-IR, SEM, TG, elemental analysis, and ICP. The results proved that HKUST-1 had typical microporous structure, and the thiol groups were incorporated into the channels of the carrier. Through the reaction of vinyl and thiol, the ionic liquid was successfully immobilized onto SH-HKUST-1 by chemical covalent bonds. The catalyst was applied in the esterification of oleic acid with ethanol, and the optimal conditions were determined as follows: molar ratio of ethanol to oleic acid 12 : 1, catalyst amount 15 wt% (based on oleic acid), reaction time 4 h, and reaction temperature 90 °C. Under the conditions, the conversion of oleic acid was 92.1%. After 5 times of recycling, there was no significant decrease in conversion, showing a certain stability and good reusability of the catalyst. The catalyst also exhibited high catalytic activity in esterification of oleic acid with other short-chain alcohols.
- Chen, Chong,Wu, Zuowang,Que, Yigen,Li, Bingxue,Guo, Qirui,Li, Zhong,Wang, Lei,Wan, Hui,Guan, Guofeng
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- Synthesis and analysis of the C1-C18 alkyl oleates
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The C1-C18 alkyl oleates were prepared in n-hexane by esterification of oleic acid with either the primary and secondary C1-C6 alcohols or the primary fatty C8-C18 alcohols. The esterification was acid-catalyzed in the presence of p-toluene sulfonic acid (p-TSA) in a pseudo-homogeneous phase, or in the presence of the sulfonic macroporous resin (K2411) in the heterogeneous phase. The purified alkyl oleates were characterized by 13C-NMR. The oleic acid/alkyl oleate mixtures were analyzed by high-performance liquid chromatography (HPLC).
- Vieville, Corinne,Mouloungui, Zephirin,Gaset, Antoine
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- An efficient activity ionic liquid-enzyme system for biodiesel production
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The efficient production of biodiesel in hydrophobic ionic liquids using immobilized lipase was demonstrated. The use of ionic liquids containing long alkyl chains on the cation has the important advantage of producing homogeneous systems at the start of the reaction but, when the reaction is complete, a three-phase system is created that allows selective extraction of the products using straightforward separation techniques, while the ionic liquid and the enzyme can be reused. Fifteen ionic liquids based on different alkyl chain length of the methyl imidazolium cation ([C10MIM], [C 12MIM], [C14MIM], [C16MIM] and [C 18MIM]) combined with [BF4], [PF6] or [NTf 2] anions were assayed as reaction media for two immobilized lipases (Candida antarctica lipase B and Pseudomonas fluorescens lipase AK) for biodiesel production. The highest synthetic activity was obtained in [C 16MIM] [NTf2] using Novozym 435 (immobilized Candida antarctica lipase with 245.13 U g-1 IME), its activity being more than three times higher than in a solvent-free system. Additionally, in this IL the fatty acid methyl esters production was 90.29% after 3 h, while in the solvent-free system it was 27.3%. The influence of several reaction parameters, such as temperature, methanol-to-oil molar ratio, alkyl-chain length of the alcohols, IL:substrate volume ratios, amount of enzyme, and oils feedstock were studied and optimized.
- De Diego, Teresa,Manjon, Arturo,Lozano, Pedro,Vaultier, Michel,Iborra, Jose L.
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- Biodiesel synthesis from the esterification of free fatty acids and alcohol catalyzed by long-chain Bronsted acid ionic liquid
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A long-chain Bronsted acid ionic liquid (IL), 3-(N,N- dimethyldodecylammonium)propanesulfonic acid p-toluenesulfonate ([DDPA][Tos]), was prepared and characterized by FT-IR, 1H NMR, 13C NMR, UV/vis and TGA. The H0 (Hammett function) value of the IL was also determined. The IL as catalyst was applied to the catalytic synthesis of biodiesel from free fatty acids (FFAs). The influencing factors, such as the type and amount of catalyst, reaction time, molar ratio of fatty acid to methanol and reaction temperature, were investigated. The results indicated that the long-chain Bronsted acid IL showed high catalytic activity and fair reusability. Esterification was accomplished under the following optimized conditions: molar ratio of alcohols to FFA at 1.5:1, mole fraction of ionic liquid at 10%, 60 °C, and 3 h. The products could be separated from the catalyst system by liquid-liquid biphase separation at room temperature with good yields of 92.5% to 96.5%. The catalyst could be reused nine times after the removal of water and alcohol. Therefore, the long-chain Bronsted acid IL has good potential for the synthesis of biodiesel from low-cost feedstocks such as waste oil and woody plant oils.
- He, Leqin,Qin, Shenjun,Chang, Tao,Sun, Yuzhuang,Gao, Xiaorui
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- Catalytic Biodiesel Production Mediated by Amino Acid-Based Protic Salts
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Hetero- and homogeneous acid catalysts are effective catalysts for the production of biodiesel from oils containing high free fatty acids. The protic salts synthesized from natural amino acids were examined for catalytic activity and efficiency for the esterification of oleic acid after structural identification and characterization. In the esterification reaction of oleic acid with methanol, [Asp][NO3] was the best catalyst, and its high activity correlated to its high Hammett acidity. The optimal reaction conditions for the esterification of oleic acid to achieve 97 % biodiesel yield were: 70 °C, 10 % catalyst loading (w/w, on oleic acid basis), methanol/oleic acid ratio 7.5:1, and 5 h. Generally, [Asp][NO3] could be a good catalyst for the esterification of oleic acid with alcohols with chain lengths of up to six. The biodiesel yield of 93.86 % obtained from palm fatty acid distillate implies that the catalyst has potential for industrial application. A study of the kinetics indicated that the reaction followed pseudo-first-order kinetics with an activation energy and pre-exponential of 57.36 kJ mol?1 and 44.24×105 min?1, respectively. The aspartic acid-derived protic salt is a promising, operationally simply, sustainable, renewable, and possibly biodegradable catalyst for the conversion of free fatty acids into biodiesel.
- Li, Jingbo,Guo, Zheng
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- Solvent-free esterification catalyzed by surfactant-combined catalysts at room temperature
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Solvent-free esterifications of various carboxylic acids and alcohols can be catalyzed by surfactant-combined catalysts dodecylbenzene sulfonic acid (DBSA) and copper dodecylbenzene sulfonate (CDBS) in moderate to excellent yield at room temperature. The esterification method has two notable advantages: first, there is no need for any solvent, even water, and secondly, no need for energy, the reaction can proceed smoothly at room temperature. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
- Gang, Li,Xinzong, Li,Eli, Wumanjiang
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- Synthesis and characterization of oleic succinic anhydrides: Structure-property relations
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Alkenyl succinic anhydrides (ASA) were prepared by an -ene reaction of n-alkyl (C1 to C5) oleates with maleic anhydride. The purified compounds were characterized by FTIR, 1H NMR, and MS analytical methods to elucidate their structures. Their physicochemical properties were systematically studied and found to depend on the length of the alkyl radical. Structure-property relations were established for viscosity, m.p., and density. The combination of a long hydrophobic chain and a highly polar group with density values close to that of water implied good emulsification properties for some of these molecules. Comparison of the thermal properties of alkyl oleates and their respective ASA demonstrated that the grafting of maleic anhydride allowed the synthesis of compounds with very low melting temperatures (less than -60°C) and good stability at high temperatures (greater than 350°C) under both air and helium atmospheres. All these properties suggest a strong potential for application in the biolubricant or surfactant fields. The combined influences of the succinic part and variable ester moieties imply that each ASA molecule has its own characteristics, based on which applications could be developed. Copyright
- Candy, Laure,Vaca-Garcia, Carlos,Borredon, Elisabeth
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- Novel porous and hydrophobic POSS-ionic liquid polymeric hybrid as highly efficient solid acid catalyst for synthesis of oleate
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A novel porous and hydrophobic Br?nsted acidic solid catalyst (POSS-[VMPS][H2SO4]) was successfully synthesized by copolymerization of polyhedral oligomeric vinylsilsesquioxanes (POSSs) and sulfonic acid-functionalized imidazole ionic liquids. Catalytic tests for the esterification of oleic acid with methanol have shown that this newly obtained polymeric hybrid exhibits very high catalytic activity and selectivity, which was more active or comparable to those of the common solid acid Amberlite-732 and liquid acid H2SO4. Moreover, the catalyst has a good recyclability without significant loss in the activity.
- Lu, Dan,Zhao, Jiwei,Leng, Yan,Jiang, Pingping,Zhang, Chenjun
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- Enzymatic Esterification of Oleic Acid with Aliphatic Alcohols for the Biodiesel Production by Candida antarctica Lipase
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Biodiesel can be obtained by esterification reactions of free fatty acids with enzymatic catalysts (lipases). In this study, the immobilized Candida antarctica lipase was employed in enzymatic esterifications of oleic acid with aliphatic alcohols (methanol, ethanol, n-propanol, n-butanol). Some features that influence the enzymatic esterification reaction, such as amount of biocatalysts, reaction time, hydration level and biocatalyst turnover were evaluated. The products were determined by GC-FID and 1H NMR analyses and these analytical methods were compared. The enzymatic catalyst (C. antarctica lipase) was efficient providing high yields of biodiesel (above 90 %) in less than 24 h to ethanol, n-propanol and n-butanol, whereas for methanol, the enzyme was inactive after ten cycles of reaction. Two new quantitative easy methods were also developed to quantify esters produced by 1H NMR based on the α-CH2 protons of oleic acid and esters. The quantification method used in the enzymatic reactions by 1H NMR showed effective with small differences in comparison with GC-FID analyses. Graphical Abstract: C. antarctica lipase was employed in enzymatic esterifications of oleic acid with aliphatic alcohols (methanol, ethanol, n-propanol, n-butanol) for the biodiesel production. A new method was developed to quantify esters produced (biodiesel) by 1H NMR based on the α-CH2 protons. [Figure not available: see fulltext.]
- Rosset, Isac G.,Cavalheiro, Maria Cecilia H. T.,Assaf, Elisabete M.,Porto, Andre L. M.
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- Br?nsted acid surfactant-combined dicationic ionic liquids as green catalysts for biodiesel synthesis from free fatty acids and alcohols
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Quaternary ammonium Br?nsted acid surfactant-combined dicationic ionic liquids (BASDILs) based on zwitterionic 1,2-bis[N-methyl-N-(3-sulfopropyl)-alkylammonium]ethane betaines and various anions were prepared and characterized. BASDILs possess properties similar to those of phase-separated catalysts and were applied to the catalytic synthesis of biodiesel from free fatty acids and alcohols. Several factors were investigated and the results indicated that [C12Sb][p-CH3C6H4SO3] was the optimal catalyst, with good catalytic performance and reusability under mild conditions.
- Chang, Tao,He, Leqin,Zhang, Xiaojing,Yuan, Mingxia,Qin, Shenjun,Zhao, Jiquan
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- Novel and highly efficient SnBr2-catalyzed esterification reactions of fatty acids: The notable anion ligand effect
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In this work, the efficiency of Lewis acid catalysts, SnX2 (X = F-, Cl-, Br-, or -OAc), was investigated on the esterification reactions of fatty acids (i.e., myristic, palmitic, stearic, oleic, linoleic, and linoleic) with different alcohols (i.e., methyl, ethyl, propyl, isopropyl, and butyl alcohol). Tin(II) bromide was the most active catalyst in all reactions studied. We investigated the effects of main reaction parameters, such as catalyst concentration, temperature, and nature of alcohol and fatty acid. The highest activity of SnBr2 catalyst was discussed in terms of its lower activation energy, higher Lewis acid strength, and higher softness of anionic ligand. Finally, the SnBr 2 catalyst can be easily recovered and reused without loss of catalytic activity. Graphical Abstract: Effect of the tin catalyst nature on the oleic acid esterification with ethyl alcohol. [Figure not available: see fulltext.]
- Ferreira, Arthur Batista,Cardoso, Abiney Lemos,Da Silva, Marcio Jose
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- Carica papaya by-products as new biocatalysts for the synthesis of oleic acid esters
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Carica papaya lipase is a versatile biocatalyst that is employed for many biotechnological purposes. Its lipase activity was first observed to be tightly linked to the insoluble fraction of latex. Nevertheless, recent studies have shown that this activity is also present in the fruit peel and seeds, suggesting that the lipase activity occurs in other parts of the plant. In the present work, the hydrolytic activity on trioctanoin was determined in various plant by-products, including latex, leafs, petioles, meristems, fruits, and the stem. The most hydrolytic activity was found in the latex (11 U/mL), followed by the petioles (1.7 U/mL). The hydrolytic selectivity was determined using triacetin, tripropionin, tributyrin, and trioctanoin. The enzymes present in the latex showed a higher rate of hydrolysis of tributyrin, while those present in the petioles had a preference for tripropionin, possibly indicating the occurrence of at least two different triacylglycerol hydrolases. Five self-immobilized biocatalysts were obtained: lyophilized latex (LL), lyophilized petioles (LP), bagasse from petioles (BP), and, after a simple cold water washing treatment, treated lyophilized latex (TLL), and treated lyophilized petioles (TLP). This procedure yielded a 5- and 10-fold increase in the latex and petiole activity, respectively, on tributyrin. The selected biocatalysts, TLL and BP, were tested for the synthesis of oleic acid esters (OAE), reaching conversions over 80%. Unexpectedly, only BP preferentially synthesized dodecyl oleate (DO) and showed the highest thermostability. Therefore, BP was further assayed for DO synthesis in a packed bed reactor (PBR), achieving 96% conversion over 40 h. This study shows the great potential of C. papaya by-products, particularly BP, as biocatalysts for the synthesis of OAE.
- Armendáriz-Ruiz, Mariana,Mateos-Díaz, Eduardo,Rodríguez-González, Jorge Alberto,María Camacho-Ruiz, Rosa,Gutiérrez-Mora, Antonia,Sandoval-Fabian, Georgina,Gallegos-Tintoré, Santiago,Mateos-Díaz, Juan Carlos
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- Investigation of the catalytic efficiency of a new mesoporous catalyst SnO2/WO3 towards oleic acid esterification
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The synthesis of a new, effective and reusable heterogeneous catalyst, mesoporous SnO2/WO3 (SW) to promote the esterification involving oleic acid and ethanol for the production of ethyl oleate is presented here. The developed mesoporous SnO2/WO3 with surface area of 130 m2/g and pore size of 3.9 nm exhibits up to 90% conversion of oleic acid (for 2 h reaction, at 80 °C) with high yield (~92%) to the ethyl oleate, a product of the esterification reaction of oleic acid. The catalyst exhibits a comparable activity of H2SO4, which is a known catalyst for esterification of organic acids. Kinetic investigation reveals that the experimental data follows a first order dependency on the concentration of the oleic acid and the catalyst. The conversion of oleic acid also has noticeable dependency on the reaction temperatures and different alcohols. Regeneration through heating of the used mesoporous SnO 2/WO3 catalyst at 400 °C for 3 h allows it for reuse without losing of its catalytic activity.
- Sarkar, Arpita,Ghosh, Sudip K.,Pramanik, Panchanan
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- Evolving the Promiscuity of Elizabethkingia meningoseptica Oleate Hydratase for the Regio- and Stereoselective Hydration of Oleic Acid Derivatives
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The addition of water to non-activated carbon–carbon double bonds catalyzed by fatty acid hydratases (FAHYs) allows for highly regio- and stereoselective oxyfunctionalization of renewable oil feedstock. So far, the applicability of FAHYs has been limited to free fatty acids, mainly owing to the requirement of a carboxylate function for substrate recognition and binding. Herein, we describe for the first time the hydration of oleic acid (OA) derivatives lacking this free carboxylate by the oleate hydratase from Elizabethkingia meningoseptica (OhyA). Molecular docking of OA to the OhyA 3D-structure and a sequence alignment uncovered conserved amino acid residues at the entrance of the substrate channel as target positions for enzyme engineering. Exchange of selected amino acids gave rise to OhyA variants which showed up to an 18-fold improved conversion of OA derivatives, while retaining the excellent regio- and stereoselectivity in the olefin hydration reaction.
- Engleder, Matthias,Strohmeier, Gernot A.,Weber, Hansj?rg,Steinkellner, Georg,Leitner, Erich,Müller, Monika,Mink, Daniel,Schürmann, Martin,Gruber, Karl,Pichler, Harald
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- Heterogenization of ionic liquid based on mesoporous material as magnetically recyclable catalyst for biodiesel production
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To develop green and reusable catalysts for the biodiesel preparation, a novel magnetically separable nanocatalyst was fabricated by covalent bonding of 3-sulfopropyl-1-(3-propyltrimethoxysilane) imidazolium hydrogen sulfate ([SO3H-PIM-TMSP]HSO4) on mesoporous silica modified Fe3O4 nanoparticle. The catalyst possessed uniform core-shell structure with magnetic response core and Br?nsted ionic liquid functionalized mesoporous silica shell. The multifunctional catalyst also exhibited appealing physicochemical features like high specific surface area, mesoporous channel, magnetic response, and fine catalytic activity in esterification of oleic acid with alcohol. Under mind conditions, the conversion of oleic acid was up to 93.5%. The catalyst exhibited recyclable property based on magnetism and the separation of the catalyst would be simply using external magnetic field without obvious mass loss, allowing a clean biodiesel product.
- Wan, Hui,Wu, Zuowang,Chen, Wen,Guan, Guofeng,Cai, Yuan,Chen, Chong,Li, Zhong,Liu, Xiaoqin
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- Chemically Modified Lipase from Thermomyces lanuginosus with Enhanced Esterification and Transesterification Activities
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Lipase from Thermomyces lanuginosus is one of the most explored enzymes for the esterification of several added-value industrial compounds, such as biodiesel, fragrances, and flavors. Its selectivity in these reactions is mostly related with its activity towards small alcohols. In this work, the impact of the chemical modification, with 4 dodecyl chains at its surface, was evaluated regarding its transesterification and esterification activities, comparing with the native form. Linear size-differentiated alcohols (from 1 to 20 carbons in the aliphatic chain) were used to explore for the first time the effect of the chain length in both transesterification and esterification reactions, using p-nitrophenyl palmitate and oleic acid as model compounds, respectively. The chemically modified lipase showed an outstanding improvement of its catalytic performance than the native enzyme, being this increase directly proportional to the size of the alcohols chain used as substrates. The enormous potential and remarkable versatility of this novel super catalyst was here demonstrated, where diverse types of esters, differing in their potential applications (biodiesel, cosmetics, fine chemistry), were efficiently synthesized. The produced esters were fully characterized by 1H NMR, GC-MS, and FTIR.
- Noro, Jennifer,Cavaco-Paulo, Artur,Silva, Carla
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p. 4524 - 4531
(2021/09/02)
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- Revealing the Roles of Subdomains in the Catalytic Behavior of Lipases/Acyltransferases Homologous to CpLIP2 through Rational Design of Chimeric Enzymes
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The lipases/acyltransferases homologous to CpLIP2 of Candida parapsilosis efficiently catalyze acyltransfer reactions in lipid/water media with high water activity (aW>0.9). Two new enzymes of this family, CduLAc from Candida dubliniensis and CalLAc8 from Candida albicans, were characterized. Despite 82 % sequence identity, the two enzymes have significant differences in their catalytic behaviors. In order to understand the roles played by the different subdomains of these proteins (main core, cap and C-terminal flap), chimeric enzymes were designed by rational exchange of cap and C-terminal flap, between CduLAc and CalLAc8. The results show that the cap region plays a significant role in substrate specificity; the main core was found to be the most important part of the protein for acyltransfer ability. Similar exchanges were made with CAL-A from Candida antarctica, but only the C-terminal exchange was successful. Yet, the role of this domain was not clearly elucidated, other than that it is essential for activity.
- Jan, Anne-Hélène,Dubreucq, éric,Subileau, Maeva
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p. 941 - 950
(2017/05/26)
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- Synthesis, characterization and catalytic performance of a novel picolinic acid-12-molybdophosphoric acid hybrid catalyst
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A novel 12-molybdophosphoric acid (HPM)-based complex (H2 PI)2(H 3 O)[PMo12O 40] [Mo2 O5 (H2 O)2 (PI)2 ]?11H2 O (PI-HPM) was prepared by modification with picolinic acid (HPI) and characterized by the methods of Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG), X-ray powder and single crystal diffraction. The complex retained the classical Keggin structure of bulk HPM, there were some strong hydrogen bonds existing between the [PMo12 O40 ]3- polyanion, the [Mo2 O5 (H2 O)2 (PI)2 ] coordination moiety, the protonated HPI and the lattice water molecules. Then PI-HPM was employed as heterogeneous catalyst for esterification reaction to evaluate its acid-catalytic activity. The complex exhibited high activity and good durability in reaction mixtures, indicating that it was a promising heterogeneous acid catalyst for esterification that including the conversion of oleic acid to oleates.
- Liu, Lijun,Wang, Honghong,Gong, Shuwen,Lu, Jing,Zhang, Qian
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p. 1007 - 1013
(2016/06/15)
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- Epoxidized fatty acid ester plasticizer epoxidized fatty acid ester plasticizer and manufacturing method
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Epoxidized fatty acid alkyl ester and methods for making epoxidized fatty acid alkyl ester. The epoxidized fatty acid alkyl ester is prepared from a fatty acid alkyl ester starting material comprising at least one of mono-unsaturated and di-unsaturated fatty acid alkyl ester molecules in a combined amount of at least 85 weight percent. Such epoxidized fatty acid alkyl esters can be employed in plasticizer compositions, either alone or in combination with other plasticizers, such as epoxidized natural oils. Such plasticizers in turn may be used in the formation of polymeric compositions.
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Paragraph 0066
(2017/01/26)
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- The 3D model of the lipase/acyltransferase from Candida parapsilosis, a tool for the elucidation of structural determinants in CAL-A lipase superfamily
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Abstract Because lipids are hydrophobic, the development of efficient bioconversions in aqueous media free of organic solvents is particularly challenging for green oleochemistry. Within this aim, enzymes exhibiting various abilities to catalyze acyltransfer reaction in water/lipid systems have been identified. Among these, CpLIP2 from Candida parapsilosis has been characterized as a lipase/acyltransferase, able to catalyze acyltransfer reactions preferentially to hydrolysis in the presence of particularly low acyl acceptor concentration and high thermodynamic activity of water (aw > 0.9). Lipase/acyltransferases are thus of great interest, being able to produce new esters at concentrations above the thermodynamic equilibrium of hydrolysis/esterification with limited to no release of free fatty acids. Here, we present a 3D model of CpLIP2 based on homologies with crystallographic structures of Pseudozyma antarctica lipase A. Indeed, the two enzymes have 31% of identity in their primary sequence, yielding a same general structure, but different catalytic properties. The quality of the calculated CpLIP2 model was confirmed by several methods. Limited proteolysis confirmed the location of some loops at the surface of the protein 3D model. Directed mutagenesis also supported the structural model constructed on CAL-A template: the functional properties of various mutants were consistent with their structure-based putative involvement in the oxyanion hole, substrate specificity, acyltransfer or hydrolysis catalysis and structural stability. The CpLIP2 3D model, in comparison with CAL-A 3D structure, brings insights for the elucidation and improvement of the structural determinants involved in the exceptional acyltransferase properties of this promising biocatalyst and of homologous enzymes of the same family.
- Subileau, Maeva,Jan, Anne-Hélène,Nozac'h, Hervé,Pérez-Gordo, Marina,Perrier, Véronique,Dubreucq, Eric
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p. 1400 - 1411
(2015/08/03)
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- Lipase activity and enantioselectivity of whole cells from a wild-type Aspergillius flavus strain
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This study reports the high enantiomeric preference of whole cell lipase from Aspergillus flavus wild-type that allows the preparation of a chiral secondary alcohol. Whole cells prepared from a wild-type Aspergillus flavus strain were used as biocatalysts to prepare (R)-1-phenylethyl acetate. (R)-1-Phenylethanol was esterified into (R)-1-phenylethyl acetate with a 94.6% enantiomeric excess (ee) within 24 h at 40 C and (S)-1-phenylethanol remained in the reaction medium with a >99%ee. Besides, this biocatalyst allows the preparation of ethyl laurate and a mixture of 2-chloro-1-(chloromethyl)ethyl acrylate and 2,3-dichloro-1-propyl acrylate. The ethyl laurate yield was 96%, whereas the synthesis of a mixture of the acrylate regioisomers, 2-chloro-1-(chloromethyl)ethyl acrylate and 2,3-dichloro-1-propyl acrylate gave similar yields to those obtained using commercial lipases.
- Solarte, Carmen,Yara-Varon, Edinson,Eras, Jordi,Torres, Merce,Balcells, Merce,Canela-Garayoa, Ramon
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- Studies on the lipase-catalyzed esterification of alkyl oleates in solvent-free systems
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The alkyl oleates were prepared by esterification of oleic acid with alkyl alcohols catalyzed by the lipase from Candida sp. 99-125 in solvent-free system. The influence of several factors, including enzyme concentration, temperature, molar ratio between oleic acid and alkyl alcohols, the structure of alcohols and water content, was also investigated. The results indicated that the reactions catalyzed by Candida sp. lipase at 20 °C, in the presence of 5% (w/w) lipase, on the molar ratio of 1:1 between oleic acid and alcohols, afforded products in high yield and showed high selectivity to primary alcohols. The enzymatic synthesis gave purer products, compared with the conventional chemical synthesis. The lipase from Candida sp. 99-125 was identified to be an effective catalyst in the esterification of alcohol and oleic acid at low temperature.
- Zhong, Hui,Fang, Zheng,Zou, Baohua,Li, Xin,Ouyang, Pingkai,Guo, Kai
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p. 114 - 117
(2013/05/08)
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- Melting points and viscosities of fatty acid esters that are potential targets for engineered oilseed
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Our previous isolation of branched-chain fatty acid (BCFA) methyl esters from lanolin was improved and scaled up. Also, oleate esters of isopropanol, oleyl alcohol and normal alcohols of 1-12 carbons chain lengths were prepared. Esters were made by interesterification with sodium alcoholates and by esterification with Candida antarctica lipase. It proved easier to obtain pure esters by the enzymatic synthesis. Melting points and viscosities over the range of 0-70 °C were determined in order to better identify potential lubricant targets that might be produced by genetically modified oilseed crops. Isopropyl and butyl oleate have melting points of -33 and -32 °C, respectively and viscosities that range from ~17 cp (0 °C) to ~2.5 cp (70 °C). They should have suitable stability for lubricants. BCFA esters had viscosities similar to their straight chain analogs. Viscosities increased with alcohol chain length and decreased with temperature. The dependence of viscosity on temperature was fit with an equation based on Erying's rate equation. Some esters with branched acid or branched alcohol moieties, and some oleate esters might be utilized as biolubricants or biofuels on the basis of their melting points and viscosities.
- Yao, Linxing,Hammond, Earl,Wang, Tong
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- Diesters from oleic acid: Synthesis, low temperature properties, and oxidation stability
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Several diesters were prepared from commercially available oleic acid and common organic acids. The key step in the three step synthesis of oleochemical diesters entails a ring opening esterification of alkyl 9,10-epoxyoctadecanoates (alkyl: propyl, isopropyl, octyl, 2-ethylhexyl) using propionic and octanoic acids without the need for either solvent or catalyst. Each synthetic diester was evaluated for both low temperature operability and oxidation stability through measurement of cloud point, pour point, oxidation onset temperature, and signal maximum temperature. It was discovered that increasing chain length of the mid-chain ester and branching in the end-chain ester had a positive influence on the low temperature properties of diesters. Improved oxidation stability is achieved when the chain length of the mid-chain ester is decreased. Additionally, the mid-chain ester plays a larger role in oxidation stability than the end-chain ester. These products may prove useful in the search for bio-based industrial materials, such as lubricants, surfactants, and fuel additives.
- Moser, Bryan R.,Sharma, Brajendra K.,Doll, Kenneth M.,Erhan, Sevim Z.
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p. 675 - 680
(2008/09/21)
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- Process for producing fatty acid alkyl ester composition
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An object of the present invention is to solve a problem of separation and recovery of catalysts present in an alkali metal catalytic method currently often used, a problem of excess consumption of a catalyst by a free fatty acid in a raw material, and other problems, and to solve a problem of the presence of a large excess amount of alcohol in a conventional supercritical methanol method, and to provide a method for producing a fatty acid alkyl ester composition in a reaction system containing water and free fatty acid present. The present invention has attained the above-mentioned object by provided a method for producing a fatty acid alkyl ester composition using fats and oils containing a fatty acid glyceride and/or fatty acid, wherein alcohol and/or water is allowed to co-exist with the above-mentioned fats and oils and the reaction is conducted under conditions of a temperature of 100° C. to 370° C. and a pressure of 1 to 100 MPa.
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Page/Page column 7-8
(2008/06/13)
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- Improvement in the gas chromatographic resolution of petroselinate from oleate
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In the extraction of oils from seeds of the genus Coriandrum, GC separations of petroselinate from oleate often gave poor resolution of these two isomers. Oleic and petroselinic acids were esterified with a series of alcohols (methanol, ethanol, 1 propanol, 2-propanol, 2-methyl-1 -propanol, 1 -butanol, 3-methyl1-butanol, and 2-ethyl-1-hexanol). GC resolution of the A6 from the Δ9 and Δ11 octadecenoates was examined for all ester derivatives on a polar phase column. The Δ6 and Δ9 isomers were unresolved as methyl esters; however, the 2-ethyl-1-hexyl esters gave baseline separation of all three isomers under temperature programming conditions. When isothermal conditions were optimized for each ester, separation of these isomers was possible with good resolution values (>89%) for all the alcohols except methanol, which had a partial resolution of 51%. The rates of esterification of all the alcohols were determined for reactions with both oleic acid and triolein using potassium hydroxide as the esterification catalyst. Methanol gave the largest rate constant in both acid and oil esterification reactions with a rate constant 10-fold better than all of the other alcohols. Based on rates of reaction, resolution of petroselinate from oleate, and removal of residual alcohol, the ethyl ester derivative appears to be the best choice for seed oils containing petroselinic acid. Copyright
- Isbell, Terry A.,Green, Lindsay A.,DeKeyser, Stephanie S.,Manthey, Linda K.,Kenar, James A.,Cermak, Steven C.
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p. 429 - 434
(2007/10/03)
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