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以交联烯丙基葡聚糖凝胶（ Ｃ Ａ Ｄ Ｂ） 为载体，以对 － β－ 硫酸酯 乙砜基苯胺（ Ｓ Ｅ Ｓ Ａ） 为 偶联活性剂，共价固定工业脂肪酶。研究了固定化脂肪酶在有机溶剂中催化酯化反应时，有机溶剂性质、脂肪酸与脂肪醇的结构、ｐ Ｈ 值、反应温度和 体系含水量等对酯化反应 结果的影响。试验结果表明：异辛 烷是最适宜的有机溶剂；脂肪酸与脂肪醇的碳链越长，越易于酯化；固 定化脂肪酶对伯醇的选择 性优于仲醇；以异辛烷为有机溶剂，在反应温度为４０ ℃、ｐ Ｈ 为７ ．４ 时，油酸与十二醇的酯化率最高；反应初期应加入少量水以激活酶，反应后期则应除去体系中的水以避免酶失活；固定化酶间歇催化油酸与十二醇的酯化时，重复使用３０ 次（ 每次２４ ｈ） ，酯化率从９３ ．５ ％ 降至４７ ．０ ％ ，其操作半衰期约为７２０ ｈ ；在柱式固定床反应器中，固定化酶连续催化油酸与十二醇酯化时，连续运行５０ ｄ 酯化率仍高达７３ ％ 。
The industrial lipase was covalently immobilized with the crosslinked allyl dextran gel (C A D B) as the carrier and the p-β-sulfatothioate aniline (S E S A) as the coupling active agent. The effects of organic solvent, structure of fatty acid and fatty alcohol, p H value, reaction temperature and system water content on the esterification reaction of immobilized lipase catalyzed by esterification in organic solvent were studied. The results showed that isooctane was the most suitable organic solvent. The longer the carbon chain of fatty acid and fatty alcohol was, the easier it was to esterify. The selectivity of immobilized lipase to primary alcohol was better than that of secondary alcohol. Solvent, p H = 7 at a reaction temperature of 40 ° C. 4, oleic acid and dodecanol the highest esterification rate; initial reaction should be added a small amount of water to activate the enzyme, the reaction should be removed later in the system of water to avoid enzyme inactivation; immobilized enzyme intermittent catalytic oleic acid and twelve Alcohol esterification, repeated use of 30 times (24 h each), esterification rate of 93. 5% to 47. 0%. The half-life of operation was about 720 h. In the fixed-bed reactor, the esterification rate of oleic acid and dodecanol was up to 73% after 50 days of continuous operation.