脂肪酶的固定化及其催化合成生物柴油

Immobilization of a Specific Lipase and Its Catalysis in Preparing Biodiesel

以丝瓜络为载体,对Pseudomonas fluorescens脂肪酶进行固定化研究。最佳固定化条件为:在25℃、正己烷介质中固定化30 min,脂肪酶与载体的配比为500 U/g。将自制固定化脂肪酶用于催化餐饮废油合成生物柴油,在反应温度40℃、餐饮废油与甲醇的摩尔比1:3(甲醇分3次加入)、水质量分数0.4%、无溶剂条件下,甲酯收率最高达88.7%。在相同反应条件下,自制固定化脂肪酶与固定化Novozym 435脂肪酶进行比较发现,自制固定化脂肪酶的综合应用性能优于固定化Novozym 435脂肪酶。自制固定化脂肪酶重复使用10次后甲酯收率仍达85.5%,适合于工业化应用。

Pseudomonas fluorescens lipase was immobilized onto luffa supporter in n-hexane medium at 25 ℃ for 30 min. The loading amount of the lipase was 500 U/g. The immobilized Pseudomonas fluorescens lipase as catalyst was used in preparation of biodiesel from waste edible oil and methanol without other solvent. Under reaction conditions ： temperature 40℃, water mass fraction 0.4%, and mole ratio of methanol to oil 3 ： 1, that methanol was divided into 3 portions and added separately to maintain the mole ratio of methanol to oil at about 1 ： 1 during reaction, the yield of methyl ester was more than 88.7%, which was higher than that from immobilized Novozym 435 lipase at same reaction conditions. After the immobilized Pseudomonas fluorescens lipase catalyst was reused 10 times, the yield of methyl ester still remained at 85.5%. It was hopeful that the catalyst be used in industrial process.