Abstract: Traditional biodiesel production primarily uses methanol as the acyl acceptor, but its toxicity to lipase increases process complexity and operational difficulty elevate manufacturing costs. This study aimed to explore a new method for enzymatic synthesis of biodiesel with methyl methacrylate (MMA) as acyl acceptor. Meanwhile, a 1, 3-position specific lipase Lipozyme RM IM was applied as biocatalyst, which enables simultaneous production of biodiesel (FAMEs) and methacrylate fatty acid glycerides (MFAGs) via specific sn-1, 3 transesterification of MMA with triglyceride. Under the optimal reaction conditions: temperature of 50 ℃, molar ratio of 4:1 for MMA to triglyceride, enzyme dosage of 7.5% (mass), and an extra water addition of 0.5% (mass); triglyceride conversion rate of 97%, and FAMEs yield of 65% could be obtained. Simultaneously, the multistage short-path distillation and column chromatographic method were combined used for the separation of the mixed products. Finally, the purity of FAME, MFADG, DMFAG, and MMFAG were 98%, 97.8%, 95.3%, and 81.78%, respectively. In this new approach, MMA demonstrates lower toxicity to lipases, allowing for straightforward addition of all the substrates without complex addition process, and enhancing operational feasibility. Meanwhile, the by-products of MFAGs could be applied as monomers in varnishes and protective coatings, which increased the value of the products. Thus, this investigation providing an alternative way to produce biodiesel, and providing a new pathway for the sustainable development of biodiesel.

Key words: Biodiesel, Methacrylated fatty acid, Transesterification, Enzymatic catalysis, Short-path distillation, Co-production

摘要： Traditional biodiesel production primarily uses methanol as the acyl acceptor, but its toxicity to lipase increases process complexity and operational difficulty elevate manufacturing costs. This study aimed to explore a new method for enzymatic synthesis of biodiesel with methyl methacrylate (MMA) as acyl acceptor. Meanwhile, a 1, 3-position specific lipase Lipozyme RM IM was applied as biocatalyst, which enables simultaneous production of biodiesel (FAMEs) and methacrylate fatty acid glycerides (MFAGs) via specific sn-1, 3 transesterification of MMA with triglyceride. Under the optimal reaction conditions: temperature of 50 ℃, molar ratio of 4:1 for MMA to triglyceride, enzyme dosage of 7.5% (mass), and an extra water addition of 0.5% (mass); triglyceride conversion rate of 97%, and FAMEs yield of 65% could be obtained. Simultaneously, the multistage short-path distillation and column chromatographic method were combined used for the separation of the mixed products. Finally, the purity of FAME, MFADG, DMFAG, and MMFAG were 98%, 97.8%, 95.3%, and 81.78%, respectively. In this new approach, MMA demonstrates lower toxicity to lipases, allowing for straightforward addition of all the substrates without complex addition process, and enhancing operational feasibility. Meanwhile, the by-products of MFAGs could be applied as monomers in varnishes and protective coatings, which increased the value of the products. Thus, this investigation providing an alternative way to produce biodiesel, and providing a new pathway for the sustainable development of biodiesel.

关键词: Biodiesel, Methacrylated fatty acid, Transesterification, Enzymatic catalysis, Short-path distillation, Co-production