荧光假单胞菌脂肪酶固定化及催化制备生物柴油的工艺研究

Immobilization of Lipase from Pseudomonas fluorescens in Sodium Alginate-gelatin and Catalyzing Biodiesel Production from Soybean Oil

研究了不同因素对制备固定化荧光假单胞菌脂肪酶的影响及固定化酶的酶学性质,并初步探讨了利用该固定化酶制备生物柴油的工艺。以海藻酸钠明胶为复合载体,采用包埋法制备固定化荧光假单胞菌脂肪酶,考察了载酶量、颗粒直径等因子对固定化效果的影响,并用制备的固定化酶进行了酶促酯交换合成生物柴油的工艺研究,考察了反应条件如酶量、反应温度、甲醇流加方式、醇油比等因素对甲酯得率的影响。试验结果表明,制备固定化荧光假单胞菌脂肪酶的最优条件为:每克载体给酶量为300 IU,选用6号注射器针头(内径为0.5 mm);通过酯交换,催化大豆油合成生物柴油的最佳反应工艺参数为:固定化酶25%,醇油比4:1,含水量6%,反应温度40℃;此条件下反应35 h后,甲酯的最高得率可达82%。

Lipase from Pseudomonas fluorescens was entrapped by drop-wise addition of an aqueous of sodium alginategelatin and immerged in a hardening solution of CaCl2. And the immobilized lipase was used to catalyze the transesterification reaction of soybean oil with methanol to produce biodiesel. Effects of immobilization conditions and enzyme amount, reaction temperature, adding ways of methanol, molar ratio of substrate on esterification were examined in details. The results indicated that the optimum immobilized operation conditions were lipase/sodium alginate ratio 300 IU, the diameter of the pinhead 6 （0.5 mm）. The opitimal conditions of the methanolysis were enzyme 25% of oil weight, methanol/oil molar ratio 4 ： 1, reacting at 40 ℃ for 35 h, and under which condition, the maximum methyl esters yield was over 82%.