For synthesizing glycerol carbonate (GC) by a reaction between glycerol (GL) and dimethyl carbonate (DMC), a lipase immobilized on magnetic organosilica nanoflowers was prepared and utilized as a biocatalyst. Candida antarctica lipase B (CALB) was chosen as a model enzyme for preparing an immobilized biocatalyst ([email protected]). The obtained [email protected] was characterized using scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy. Effects of GL/DMC molar ratio, biocatalyst amount, temperature, surfactant and molecular sieve addition, and reaction time on the conversion of GL and the selectivity of [email protected] were investigated. The optimal catalytic performance (yield of GC: 88.66% and conversion of GL: 94.24%) was achieved under the condition of 1:20 molar ratio of GL to DMC with 0.2 g of molecular sieves added at 50 °C for 24 h. After recycling seven times, the [email protected] maintained over 79% of its initial activity and the yield of GC was 70.31%.

中文翻译：

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使用固定在磁性有机硅纳米花上的脂肪酶作为催化剂酶法合成碳酸甘油酯

为了通过甘油（GL）和碳酸二甲酯（DMC）之间的反应合成碳酸甘油酯（GC），制备了固定在磁性有机二氧化硅纳米花上的脂肪酶并将其用作生物催化剂。选择南极假丝酵母脂肪酶 B (CALB) 作为制备固定化生物催化剂的模型酶 ([email protected])。使用扫描电子显微镜、透射电子显微镜和共焦激光扫描显微镜对获得的[email protected]进行了表征。研究了GL/DMC摩尔比、生物催化剂用量、温度、表面活性剂和分子筛添加量以及反应时间对GL转化率和[email protected]选择性的影响。当GL与DMC摩尔比为1:20，添加0.2 g分子筛，50 ℃反应24 h时，催化性能达到最佳（GC产率：88.66%，GL转化率：94.24%）。循环7次后，[email protected]仍保持初始活性的79%以上，GC收率为70.31%。