钛硅-1分子筛催化丙酮氨氧化反应条件优化

Optimization of reaction conditions for acetone ammoxidation over titanium silicalite-1

采用逐级优化的单因素实验考察钛硅-1分子筛(TS-1)催化丙酮氨氧化合成丙酮肟的反应条件.结果表明:催化剂用量、氨酮摩尔比、氧酮摩尔比、氨水及双氧水滴加时间、氨水及双氧水滴加组合模式、叔丁醇与水体积比及反应温度等因素对反应效果影响较显著.适宜的反应条件为:每mol丙酮催化剂用量4g以上,氨酮摩尔比2.0以上,氧酮摩尔比1.0～1.4,氨水及双氧水滴加时间不小于1h,且同时滴加完毕,后续反应时间不小于1h,V(叔丁醇)/V(水)=2.3,反应温度70℃.在此优化反应条件下,丙酮转化率可达95%,丙酮肟选择性为98%.

The reaction conditions of acetone ammoxidation with NH3 and H2O2 as ammoxidation agents over titanium silicalite-1 （TS-1） toward acetone oxime were investigated by single factor experiments. Results showed that the catalyst amount, n（ NH3 ）/n（ acetone） , n（ H2O2 ）/n（acetone）, the addition time of NH3· H2O and H2O2, the ways to introduce NH3· H2O and H2O2, V（tert-butyl alcohol）/V（ H2O） , and the reaction temperature have a remarkable influence on the reaction. The conversion of the acetone and the selectivity to acetone oxime can reach 95% and 98% under the optimized operation conditions as follows： m（ catalyst ） /n （ acetone ） was larger than 4 g/mol, n （ NH3 ）/n （acetone） was above 2. 0, n（H2O2）/ n（acetone） was at 1.0 - 1.4, the addition time of NH3 ·H2O and H2O2 was larger than 1 h, and the dropwise of NH3.H2O and H2O2 at one time, and the following reaction time longer than 1 h, the V（tert-butyl alcohol）/V（ H2O） at about 2. 3, and the reaction temperature at about 70 ℃.