کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
70667 48840 2010 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Ectoine improves yield of biodiesel catalyzed by immobilized lipase
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Ectoine improves yield of biodiesel catalyzed by immobilized lipase
چکیده انگلیسی

To improve the production of biodiesel by enzymatic conversion of triglycerides in cottonseed oil, compatible solutes were added to the solvent-free methanolysis system to prevent competitive methanol inhibition on the immobilized lipase (Novozym® 435). The results indicated that the addition of ectoine increased biodiesel synthesis using a three-step methanol addition process. The concentration of methyl ester (ME) reached a maximum of 95.0% in the presence of 1.1 mmol/l ectoine, an increase of 20.9% compared to that in the absence of ectoine. On the other hand, excess ectoine decreased the ME concentration. Ectoine was also shown to enhance reuse of the immobilized lipase, significantly improving ME concentrations in each recycling test. Total concentrations of ME with added ectoine were about 1.5 times that without ectoine during five recycling tests (molar ratio of cottonseed oil to methanol, 1:4). Enzymatic reaction kinetics showed, in the concentration ranges of 0.8–1.14 mol/l and 0.03–8 mol/l for triglyceride and methanol, respectively, that ectoine had no effect on the initial reaction rates when methanol concentrations were below 0.5 mol/l. When methanol concentration exceeded 0.5 mol/l, the addition of 0.8 mmol/l ectoine increased the initial reaction rates, and the lipase exhibited a lower affinity for methanol and higher affinity for triglyceride (kinetic parameters of KmA increase, KmTG decrease). However, the initial reaction rates decreased significantly when 8 mmol/l ectoine was added, with the lipase having higher affinity for methanol and lower affinity for triglyceride (KmA decrease, KmTG increase). The supplementation of ectoine provided a new method for the purpose of improving yield of biodiesel catalyzed by enzyme.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Catalysis B: Enzymatic - Volume 62, Issue 1, 2 January 2010, Pages 90–95
نویسندگان
, ,