【作者】 王海鸥；

【导师】 王延吉；

【作者基本信息】 河北工业大学 ， 生物化工， 2005， 硕士

【摘要】 甲苯二异氰酸酯(TDI)是一种重要的有机中间体,主要用于制造聚氨酯泡沫塑料。用碳酸二甲酯(DMC)代替光气合成甲苯二氨基甲酸甲酯(TDC),进而分解生成甲苯二异氰酸酯(TDI)是一条绿色合成路线。生物酶在有机溶剂中有较强的催化活性,且具有反应条件温和、后处理容易、结构稳定、不容易失活等优点。所以,本文选用生物酶作催化剂,研究了酶在碳酸二甲酯与甲苯二胺合成甲苯二氨基甲酸甲酯反应中的作用,并通过数学方法进行了深入的分析。通过对十一种酶的筛选,确定木瓜蛋白酶、风味蛋白酶、胃蛋白酶和猪肝酯酶对本反应有一定的催化活性。发现对本反应具有较高催化活性和选择性的催化剂为木瓜蛋白酶。并筛选出适宜溶剂四氢呋喃,溶剂用量为15ml/g papain。对反应条件进行了优化,当温度40℃、n(TDA)/n(DMC)=1/20、 酶浓度17. 4mg/ml、反应时间40min时,TDC产率达到3. 94%。采用响应曲面法考察了TDC产率受酶浓度(3. 5～31. 3 mg/ml)、DMC用量(6. 9～20. 7 ml)和反应温度(25～55℃)三个因素的交互作用影响。通过对拟和方程的深入分析可知,TDC产率最高可达4. 02%。对影响木瓜蛋白酶酶活的诸多因素进行了研究。得到在酶浓度1mg/ml,PH值7. 0,反应温度40℃,激活剂半胱氨酸盐酸盐浓度0. 04mol/l,反应时间30分钟,保温时间30分钟的条件下,木瓜蛋白酶具有最优催化活性。通过实验发现,有机溶剂四氢呋喃、碳酸二甲酯对木瓜蛋白酶酶活有一定影响。当四氢呋喃浓度为60%(V/V)时,酶活达到最大为12. 84×10~U/mg;当DMC浓度为40%(V/V)时,酶活达到最大为9. 76×10~5U/mg。更多还原

【Abstract】 Toluene Diisocyanate ( TDI), an important organic medium, is mainly applied in the making of poly urethane(PU). The method that Toluene Dicarbamate(TDC)is synthesized by Dimethyl Carbonate (DMC) instead of phosgene, and then is decomposed and forms TDI is a green and healthy way.Biological enzyme is characterized by a strong catalytic activity in the organic solvent, and it has many advantages, such as mild reaction requirement, easy aftertreatment, stable structure, and retaining activity, etc. therefore, I chose biological enzyme as the catalyzer, and by means of mathematical analysis, I studied the function of enzyme in the synthetic process TDC by DMC and TDA.After making selection to 11 enzymes, papin, flavourzyme, pepsin, and eaterase from porcine liver are proved to have catalytic activity to the reaction, and I found out the catalyzer that has fairly strong catalytic activity and selectivity- papain. What’s more, I sorted out the most suitable solvent- Tetrahydrofuran, with 15ml/g papain. And an optimization to the reaction is made, when the temperature is 40 °C, n(TDA)/n(DMC)=l/20, and the enzyme concentration is 17.4mg/m, the TDC yield can reach 3.94% after reacting for 40 minutes.With the response surface methodology, I studied the influence of the interaction of three factors to the rate of production of TDC. The three factors are: enzyme concentration (3.5-31.3 mg/ml) , the volume of DMC (6.9-20.7 ml) and the temperature for reaction (25~55℃) . Through further analysis to the equation, it is learned that the rate of production of TDC has a great value 4.02% within chosen limits.I made a study to the multiple factors that will affect the activity of Papin. Papin has the best catalytic activity under the following conditions: enzyme concentration is 1 mg/ml, value of PH 7.0, temperature of reaction 40℃, the concentration of the activator CYS HC1 0.04mol/l, time for reaction 30 minutes, and time for keeping temperature 30 minutes. After the experiment, it is found that the organic solvent Tetrahydrofimuu DMC can influence the enzyme activity of Papin to a certain degree. When the concentration of Tetrahydrofuran is 60% (V/V) , the enzyme activity can reach its highest value 12.84 X 105U/mg; when the concentration of DMC is 40% (V/V) , the enzyme activity can reach its highest value 9.76 X 105U/mg.更多还原