二氧化碳与氢气合成二甲醚催化剂的研制

STUDY ON CATALYSIS FOR CONVERSION OF CARBON DIOXIDE TO DIMETHYLETHER IN HYDROGENATION

以二氧化碳为原料 ,加氢催化制甲醇和二甲醚具有重要的社会经济意义。研究采用CNJ2 0 2合成甲醇催化剂和HZSM - 5沸石分子筛制得了二氧化碳加氢一步法合成甲醇及二甲醚双功能催化剂。实验测试结果表明 ,该催化剂合适的配比是HZSM - 5 /CNJ2 0 2 =0 .5 (m) ,合适的焙烧温度 5 5 0℃ ,还原条件是在以N2 为载气 ,2 %H2 气氛中 ,于 2 5 0℃、常压下还原 6h。催化剂粒度和不太大的操作空速变化对二甲醚选择性无明显影响 ,提高反应温度有利于增大二甲醚的选择性。测试显示 ,进一步改进双功能催化剂 ,可望大幅度提高C0 2 转化率 ,获得较高的生成二甲醚的选择性 。

Carbon dioxide is rich in nature, so the study of its conversion to methanol and dimethylether is with important social and economical values. The bifunctional catalyst, which is made up of the two kinds of materials: CNJ202 catalyst and HZSM-5 is used to synthesis methanol and dimethylether in the experiment. The result shows that the two parts of the bifunctional catalyst make function independently. Under the experimental condition, the suitable ratio of HZSM-5/CNJ202 is R=0.5(wt/wt); the catalyst's most suitable baking temperature is 550℃; the catalyst can be reduced well under atmospheric pressure, at the temperature of 250℃, in the gas of N 2 that contains 2%H 2;the best reaction temperature is 260℃; The size of the catalyst and higher space velocity make no evident effect on the selectivity of dimethylether, but higher temperature is beneficial to the selectivity of dimethylether. The study shows that further improvement for the bifunctional catalyst can make it possible to meet the needs of CO 2 hydrogenation industrialization.