高氯酸锌催化尿素与1,2-丙二醇合成碳酸丙烯酯

Synthesis of propylene carbonate from urea and 1,2-propylene glycol over zinc perchlorate hexahydrat catalysts

摘要:

针对尿素醇解合成碳酸丙烯酯工艺，系统考察了锌盐催化体系的催化反应性能。实验结果显示锌盐均表现出良好的催化活性，其中高氯酸锌的催化效果最好；高氯酸根离子强的吸电性可能是高氯酸锌催化效果好的主要原因。以高氯酸锌催化剂，考察了不同的反应时间、催化剂用量和反应温度对合成中各个反应的影响。当n(1, 2-丙二醇):n(尿素)=4:1、反应时间3 h、催化剂质量分数1.5%、反应温度170 ℃时，碳酸丙烯酯的收率可以达到94.2%。催化剂的稳定性较好，具有一定的应用前景。

Abstract:

Zinc salts are active catalysts for the reation of urea and 1,2-propylene glycol, especially zinc perchlorate hexahydrat which shows very excellent catalytic activity.The effects of reaction time，dosage of catalyst and reaction temperature on the synthesis are investigated．The optimized reaction conditions are shown as follows: 4 of molar ratio of 1, 2-propanediol to urea, 3 h of reaction time, 1.5% of catalyst mass fraction ( based on all reaction materials) and170℃ of reaction temperature. Under the optimal reaction condition，the yield of propylene carbonate can reach over 94.2% . Electron withdrawing ability of perchlorate ion might be the key factors that influenced the catalytic activities.