W/Sn/Mg复合氧化物催化合成过氧乙酸的工艺研究

The synthesis and the technological study of peroxyacetic acid catalyzed by composite oxides W/Sn/Mg

采用沉淀法制备W/Sn/Mg复合氧化物催化剂,并用其催化乙酸(AA)和过氧化氢(HP)制备过氧乙酸(PAA).考察了催化剂用量、带水剂种类及用量、乙酸与双氧水的摩尔比以及反应时间对产品收率和所得液中平衡水含量的影响,并用正交实验对反应条件进行优化.实验结果表明,适宜的反应条件为:催化剂用量1.5g,n(HP)∶n(AA)=0.5∶1,带水剂乙酸丁酯100g,反应时间10h,在此条件下,过氧乙酸的收率可达33.83%,反应液中含水量可降低至3.0%左右;催化剂在重复使用一次后,过氧乙酸收率为19.62%,催化活性降低的原因可能是其表面吸附了有机物,部分活性中心被覆盖以及活性组分WO3流失.

Peroxyacetic acid （PAA） was synthesized from acetic acid （AA） and hydrogen peroxide （HP） on W/Sn/ Mg composite oxides catalyst. The catalyst was prepared by precipitation method. Influencing factors of end product yield and the water content were investigated. Orthogonal experiment was used to optimize reaction conditions. The optimal reaction conditions are： 1.5 g catalyst mass, n（HP） ： n（AA） as 0.5 ： 1, 100 g butyl acetate as water-carrying agent, and 10 hours of reaction time. Under the above conditions the yield of peroxyacetic acid is 33.83%, and the water content is able to be reduced to about 3%; the yield of PAA is reduced to 19.62% after catalyst was being used for one time, and catalyst deactivation is mainly due to covering of active sites by organic substances and losing of active component WO3.