The objective of this study was to use n -hexane containing an ionic liquid for the extraction of oil and transesterification for the production of methyl esters from Jatropha curcas oil. A solid acidic ionic liquid polymer was synthesized using vinyl imidazole, 1,3-propane sultone, N , N -dimethylhexadecyl amine, allyl bromide, toluene, and the product was characterized by NMR and used for the transesterification. The optimum reaction conditions that resulted in the highest methyl ester yield of 94% were a J. curcas oil-to-dimethyl carbonate molar ratio of 1:5, a solid acidic ionic liquid polymer catalyst loading of 260 wt%, for 6 h with 500 rpm at 80 °C. Methyl esters were purified using celite powder and then analyzed by GC–MS. The activation energy and reaction rate constant were calculated from 4.862 to15.382 kJ/mol, and 0.389 to 4.602, respectively. The methyl esters met the quality standards defined under ASTM D6751-02.
Biodiesel is recognized as green and renewable energy with low carbon intensity and less environmental impacts. The preparation of an economical immobilized lipase becomes much urgent challenge in the enzymatic production of biodiesel. In this study, recombinant Thermomyces lanuginosus lipase (TLL) was immobilized on the surface of silica-containing materials mediated by solid-binding peptides (SBPs). The obtained immobilized biocatalysts were effective in converting the oil from Jatropha curcas into biodiesel. The appropriate attachment mode of SBPs and TLL was investigated firstly, and the results showed that the activity of TLL was not negatively affected only when SBPs were fused at the C-terminus of TLL. Secondly, the immobilization efficiency of different SBPs (CecA, EctP1, VKT) on different silica-containing materials (SiO 2 , zeolite ZSM-5, SAR-100, MCM-41 and Na-Y) was systematically studied and it was concluded that the best immobilization efficiency was achieved for TLL-EctP1 immobilized on zeolite ZSM-5 (TLL- EctP1 @ZSM-5). TLL-EctP1 @ZSM-5 was found great performance in stability of pH, temperature, elution and storage. Eventually, biodiesel yield of 93 wt% was achieved using TLL-EctP1 @ZSM-5 as a biocatalyst to catalyze J. curcas oil for 48 h, and 81% of its initial yield was retained after 7 cycles of reuse. These results highlight the application of solid-binding peptides in enzyme immobilization for biocatalysts used in preparation of biodiesel or other chemicals.