合成醋酸乙烯催化剂制备条件的研究

STUDY ON THE PREPARATION CONDITION FOR CATALYST OF SYNTHESIZING VINYL ACETATE

采用过量浸渍法制备乙炔气相法合成醋酸乙烯催化剂醋酸锌/活性炭,对制备条件进行了研究.结果表明,较合适的浸渍条件为醋酸锌浓度0.8mol/L,平衡时间60min,浸渍温度55℃.120℃下干燥30min水分就完全烘干,而90℃下干燥70min催化剂才达到恒重.由比表面积分析可知,随着干燥温度的升高,中孔被堵塞,催化剂的平均孔半径减小;干燥温度高于110℃后,比表面积和平均孔半径变化不明显.由SEM可以看出,催化剂表面明显存在醋酸锌晶体.

The zinc acetate/activated carbon catalyst which was used in vinyl acetate synthesis from acetylene was prepared by excessive impregnation and the impregnation condition were studied. The results show that the suitable zinc acetate concentration is 0.8 mol/L. The time is 60 min. The temperature is 55 ℃. Water complete drying needs 30 min at 120 ℃, but it needs 70 min at 90 ℃. The BET analysis showed that mesopore of catalyst is blocked and the average pore radius reduce during the dry temperature increase. The BET and average hole radius don＇t change clearly when the dry temperature reaches 110 ℃. The SEM analysis shows that vinyl acetate crystal is on the catalyst surface.