期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
Encapsulation of lipases on coordination polymers and their catalytic performance in glycerolysis and esterification
1
作者 Can Zeng Nanjing Zhong 《Grain & Oil Science and Technology》 CAS 2023年第3期113-119,共7页
In this study,lipases of CALB(Candida antarctica lipase B),TLL(Thermomyces lanuginosa lipase),RML(Rhizomucor miehei lipase),CALA(Candida antarctica lipase A)and LU(Lecitase?Ultra)were encapsulated into the nucleotideh... In this study,lipases of CALB(Candida antarctica lipase B),TLL(Thermomyces lanuginosa lipase),RML(Rhizomucor miehei lipase),CALA(Candida antarctica lipase A)and LU(Lecitase?Ultra)were encapsulated into the nucleotidehybrid metal coordination polymers(CPs)for diacylglyerols(DAG)preparation.Guanosine 5'-monophosphate(GMP)and adenosine 5'-monophosphate(AMP)were used as coordinating molecules,and metal ions of Fe^(3+),Ba^(2+),Mn^(2+),Ni^(2+)and Cr^(3+)were applied to prepare matrix.Results indicated that,besides Ba^(2+)with AMP,all other metal ions can coordinate with AMP and GMP to generate CPs.In addition,the AMP/Ni was amorphous when standing temperature was 4℃,while it was crystalline when standing temperature was from 30 to 180℃.DAG content from 47.55%to 64.99%was obtained from glycerolysis by CALB@GMP/Ba,RML@GMP/Ba,TLL@GMP/Ba,RML@GMP/Mn and TLL@GMP/Mn.Additionally,CALB@GMP/Fe showed selectivity towards DAG formation in the esterification and DAG content up to 61.88%was obtained. 展开更多
关键词 LIPASE Coordination polymers ENCAPSULATION glycerolysis ESTERIFICATION
下载PDF
Enzymatic Glycerolysis of Chinese Vegetable Tallow Fraction by Lipase and Study of the Mechanism 被引量:4
2
作者 尹春华 刘涛 谭天伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期656-662,共7页
Glycerolysis of Chinese vegetable tallow (CVT) fraction was investigated using a 1,3-specific lipase from Rhizopus arrhizus as catalyst. Based upon a binary gradient HPLC with an evaporative light-scattering detector ... Glycerolysis of Chinese vegetable tallow (CVT) fraction was investigated using a 1,3-specific lipase from Rhizopus arrhizus as catalyst. Based upon a binary gradient HPLC with an evaporative light-scattering detector (ELSD), the contents of free fatty acids (FFA), monoglycerides (MG), diglycerides(DG) and triglycerides (TG)with their positional isomers during the glycerolysis were determined. The effects of water content and the ratio of glycerol to oil on the product distribution of glycerolysis were studied. Under the optimum reactant conditions:250 units lipase per gram oil at 37 ℃ with 1:2 molar ratio of oil to glycerol in a solvent-free system, after 24 h reaction, the product consisted of 7.2% TG, 25.6% MG, 56.1% DG and 4.9% FFA (all by mass). Furthermore, the mechanism of glycerolysis was discussed in detail. 展开更多
关键词 glycerolysis Rhizopus arrhizus LIPASE Chinese vegetable tallow
下载PDF
Kinetic study and kinetic parameters of lipase-catalyzed glycerolysis of sardine oil in a homogeneous medium 被引量:2
3
作者 Angela García Solaesa María Teresa Sanz +1 位作者 Sagrario Beltrán Rodrigo Melgosa 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期596-606,共11页
The production of polyunsaturated fatty acids (PUFAs) concentrates by enzymatic catalysis has gained interest due to their stereospecificity and the milder conditions employed compared to the use of inorganic cataly... The production of polyunsaturated fatty acids (PUFAs) concentrates by enzymatic catalysis has gained interest due to their stereospecificity and the milder conditions employed compared to the use of inorganic catalysts. The enzymatic glycerolysis of sardine oil by Lipozymeò435 to get PUFA concentrates in the forms of di‐and monoacylglycerols (DAGs, MAGs) in an optimized amount of tert‐butanol as the organic solvent was studied. First, mass transfer limitation of the reaction sys‐tem was analyzed. The effects of different operating variables such as lipase loading, temperature and feed composition were investigated. A semi‐empirical kinetic model based on the reversible elementary reactions of glycerolysis and hydrolysis of the glycerides was employed to correlate the experimental kinetic data. A molar ratio glycerol:oil of 3:1 was the optimum, which produced more than 84 wt%of MAG at 323 K. A comparison with other glycerolysis systems was performed using MAG yield, reaction rate and significance of kinetic parameters. 展开更多
关键词 LIPASE glycerolysis TERT-BUTANOL Mass transfer Kinetic model
下载PDF
Low Temperature Glycerolysis as a High FFA Pre-Treatment Method for Biodiesel Production
4
作者 Godlisten G. Kombe Abraham K. Temu +2 位作者 Hassan M. Rajabu Godwill D. Mrema Keat Teong Lee 《Advances in Chemical Engineering and Science》 2013年第4期248-254,共7页
A novel low temperature glycerolysis process for lowering free fatty acid (FFA) in crude jatropha oil for alkali catalyzed transesterification has been developed. The response surface methodology (RSM) based on centra... A novel low temperature glycerolysis process for lowering free fatty acid (FFA) in crude jatropha oil for alkali catalyzed transesterification has been developed. The response surface methodology (RSM) based on central composite design was used to model and optimize the glycerolysis efficiency under three reaction variables namely;reaction time, temperature and glycerol to oil mass ratio. The optimum conditions for highest glycerolysis efficiency of 98.67% were found to be temperature of 65℃, reaction time of 73 minutes and 2.24 g/g glycerol to oil mass ratio. These conditions lower the high free fatty acid of crude jatropha oil from 4.54% to 0.0654% which is below 3% recommended for alkali catalyzed transesterification. The pre-treated crude jatropha oil was then transesterified by using homogeneous base transesterification resulting to a conversion of 97.87%. The fuel properties of jatropha biodiesel obtained were found to be comparable to those of ASTM D6751 and EN 14214 standards. The process can also utilize the crude glycerol from the transesterification reaction, hence lowering the cost of biodiesel. The glycerolysis is easier implemented than acid esterification thereby avoiding the need for neutralization and alcohol removal step. 展开更多
关键词 BIODIESEL glycerolysis Free FATTY ACID Re-Esterification
下载PDF
Economic Analysis of Biodiesel and Glycerol Carbonate Production Plant by Glycerolysis
5
作者 Nghi Nguyen Yasar Demirel 《Journal of Sustainable Bioenergy Systems》 2013年第3期209-216,共8页
Techno-economic analysis of an indirect use of carbon dioxide within the route of glycerolysis of glycerol with urea is investigated. The results show that the net present value of the biodiesel-glycerol carbonate pro... Techno-economic analysis of an indirect use of carbon dioxide within the route of glycerolysis of glycerol with urea is investigated. The results show that the net present value of the biodiesel-glycerol carbonate production by glycerolysis is higher than the biodiesel-glycerol carbonate production by direct carboxylationat at the end of the 12-year operation with similar capacities. The stochastic model has predicted that using glycerolysis route for the synthesis of glycerol carbonate production might increase the probability of getting positive net present value by about 15%. 展开更多
关键词 BIODIESEL Direct Carboxylation glycerolysis Glycerol Carbonate Economic Analysis
下载PDF
Enzymatic preparation of mono-and diacylglycerols:A review
6
作者 Jiawei Zheng Yudong Liang +5 位作者 Jiaxi Li Shuping Lin Qiangyue Zhang Kanghua Zuo Nanjing Zhong Xuebing Xu 《Grain & Oil Science and Technology》 CAS 2023年第4期185-205,共21页
Monoacylglycerols(MAGs) and diacylglycerols(DAGs) are partial glycerides widely used in food industry. They are safe and non-toxic food emulsifiers, especially for MAGs. MAGs account for approximately 75% of the total... Monoacylglycerols(MAGs) and diacylglycerols(DAGs) are partial glycerides widely used in food industry. They are safe and non-toxic food emulsifiers, especially for MAGs. MAGs account for approximately 75% of the total emulsifiers in food industry worldwide. DAGs are recognized as functional cooking oils, they can suppress body fat accumulation and postprandial serum triacylglycerols(TAGs) level. The traditional production of MAGs and DAGs is based on the chemical method, which requires high reaction temperature usually up to 200–260 ℃. Such high temperature is not suitable for oil containing heat sensitive polyunsaturated fatty acids. Enzymatic approach has been received increasing attentions. Enzymatic production of partial glycerides to replace chemical processes has been in industry, particularly for DAGs production as the products have been claimed as a functional and nutritional oil. Enzyme technology for the processing of oils and fats has been moved to industry step by step and case by case during the last 20 years. More and more applications are particularly moving into bulky oils and fats processing. At the same time, the cost of enzymes as a commercial product is reducing steadily. This review summarized the recent 15 years advances on the the enzymatic preparation of MAGs and DAGs. The critical process parameters under different reaction routes were presented and emphasized. The reaction media not only increased the homogeneity of the reaction system, but also shifted the reaction equilibrium towards the target product generation, and this part was stated in detail. In addition, the patent evaluation was included, and the application of MAGs and DAGs was covered. 展开更多
关键词 MONOACYLGLYCEROL DIACYLGLYCEROL Enzymatic production ESTERIFICATION glycerolysis TERT-BUTANOL Ionic liquids Patent evaluation
下载PDF
Pre-Treatment of High Free Fatty Acids Oils by Chemical Re-Esterification for Biodiesel Production—A Review
7
作者 Godlisten G. Kombe Abraham K. Temu +3 位作者 Hassan M. Rajabu Godwill D. Mrema Jibrail Kansedo Keat Teong Lee 《Advances in Chemical Engineering and Science》 2013年第4期242-247,共6页
Non edible oil sources have the potential to lower the cost of biodiesel. However, they usually contain significant high amounts of free fatty acids (FFA) that make them inadequate for direct base catalyzed transester... Non edible oil sources have the potential to lower the cost of biodiesel. However, they usually contain significant high amounts of free fatty acids (FFA) that make them inadequate for direct base catalyzed transesterification reaction (where the FFA content should be lower than 3%). The present work reviews chemical re-esterification as a possible method for the pre-treatment of high FFA feedstock for biodiesel production. The effects of temperature, amount of glycerol, type and amount of catalyst have been discussed. Chemical re-esterification lowers FFA to acceptable levels for transesterification at the same time utilizing the glycerol by product from the same process. Further researches have been proposed as a way forward to improve the process kinetics and optimization so as to make it more economical. 展开更多
关键词 CHEMICAL Re-Esterification HIGH Free Fatty Acid glycerolysis Biodiesel FEEDSTOCK
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部