【摘要】 为了提高碳酸二乙酯的转化率与选择性,对二氧化碳和乙醇直接合成碳酸二乙酯的过程进行了研究。确定了较优的催化剂为ZrO2和3A分子筛作为混合催化剂。对催化剂的制备工艺进行了优化:采用正相沉淀方式,沉淀pH值为9,焙烧温度为600℃时制备的ZrO2按质量比为5∶2的比例与3A分子筛进行物理混合后催化效果最佳。在乙醇和二氧化碳的进料比为514/225 mmol下,碳酸二乙酯的产量可以达到0.054 3 mmol,选择性在60%以上。在该催化体系中,加入脱水剂乙烯、环氧丙烷和环氧丁烷均无法达到高效提高反应产率的效果。更多还原

【Abstract】 The catalyst used in synthesis of diethyl carbonate( DEC) from CO2and ethanol was studied in order to improve the production and selectivity. The mixture of zirconium oxide( ZrO2) and 3A molecular sieves was selected as the optimal catalyst. The preparation methods of catalysts were also optimized. ZrO2was obtained by the precipitation method at pH = 9 and then calcined at 600 ℃. ZrO2and 3A molecular sieves were mixed as the mass ratio of 5∶ 2. When the feed ratio of CO2and ethanol was 514 /225 mmol,the yield of DEC could reach 0. 054 3mmol with the selectivity of more than 60%. In the catalytic system,adding dehydrating agent into the reaction can not efficiently improve the reaction yield.更多还原