Abstract
Dioctyl sebacate is a long carbon chain dibasic acid ester with methylene as the main body. It is widely used in plasticizers because of its good cold resistance and high viscosity. And it has excellent properties of non-toxicity and easy biodegradation, so it can be used as a potential new green bio-based plasticizer. At present, most of the preparation methods of dioctyl sebacate are chemical methods, which have many by-products and cause environmental pollution. In this article, cellulose microspheres were used as a carrier to immobilize Candida antarctica lipase B (CALB) to catalyse the esterification of sebacic acid and n-octanol to prepare dioctyl sebacate. Through single factor experiments, the lipase immobilized on cellulose microspheres was optimized to determine the best process conditions: add 500 µL CALB to the erlenmeyer flask, and then add 0.02 mol/L PBS buffer (pH 8.0). After being prepared into a 5 mL system, 0.1 g of cellulose microspheres were added as a carrier and reacted for 3 h at 35 °C and 180 r/min. Added 0.5 vt% polyethylene glycol diglycidyl ether (PEGDEG) to the system for crosslinking. The final immobilization rate of lipase immobilized on cellulose microspheres was 80.06%, and the enzyme activity was 288.07 U/g. Using the cellulose-immobilized lipase as a catalyst, in the toluene system, the molar ratio of n (sebacic acid)/n (n-octanol) substrate was 1:3.5, the amount of immobilized enzyme was 0.04 g, 4 Å molecular sieve 1.5 g, 40 °C, and 150 r/min for 30 h, the conversion rate of dioctyl sebacate was 76.45%.
Acknowledgements
We would like to thank Teacher Hua Zhou and Teacher Dingqiang Lu for their support of our experiments. And thank our entire team for their contribution to the experiments.
Author contributions
All authors contributed to the study conception and design. Yuyang Zhou: Participated in the whole experiment; Rongchen Mang and Huiyi Long: Participated in the testing of experiments; Yamiao Li: Participated in data analysis; Hua Zhou and Dingqiang Lu: Theoretical support. All authors commented on previous versions of the manuscript and all authors read and approved the final manuscript.
Disclosure statement
The authors have no relevant financial or non-financial interests to disclose.
Data availability statement
We declare that the submitted work has not previously been published in full, and is not being considered for publication, elsewhere. And we declare that the submitted work has not previously been published in full, and is not being considered for publication, elsewhere.