TS-1分子筛催化苯酚和草酸二甲酯合成草酸二苯酯

Synthesis of Diphenyl Oxalate by Transesterification of Dimethyl Oxalate with Phenol over TS-1 Catalyst

研究了以 TS-1分子筛为催化剂 ,苯酚和草酸二甲酯酯交换合成草酸二苯酯反应。通过对催化剂进行吸附吡啶的红外光谱和 NH3-TPD表征 ,确定了弱的 Lewis酸位是催化苯酚和草酸二甲酯酯交换合成草酸二苯酯反应的活性位 ,同时考察了焙烧温度对 TS-1结构及催化活性的影响 ,确定了最佳焙烧温度为 5 5 0℃。以 5 5 0℃焙烧的 TS-1为催化剂 ,苯酚和草酸二甲酯的摩尔配比为 5∶ 1 ,催化剂用量 1 .8g,反应时间 4h,DMO转化率 3 0 .0 % ,MPO和 DPO总选择性 99.3 % ,MPO收率 2 6.3 % ,DPO收率 3 .4%。

The preparation of diphenyl oxalate(DPO) by transesterification of dimethyl oxalate(DMO) with phenol over TS 1 catalyst(2 5%Ti) has been investigated as function of calcination temperature of the catalyst and reaction time. The catalysts were characterized by FTIR of absorbed pyridine and NH 3 TPD. The results showed that weak Lewis acid sites were the active sites of the catalyst in the transesterification reaction. The optimum calcination temperature appeared to be 550 ℃ when its effect on the active sites and surface area of the catalysts were taken into consideration . At atmosphere pressure, reaction temperature 180 ℃, 4 h, n (PhOH)∶ n (DMO)= 5∶1 , 1 8 g catalyst, the following results were obtained:total selectivity of methylphenyl oxalate(MPO) and DPO was 99 3%, DMO conversion 30 0%, MPO yield 26 3% and DPO yield 3 4%.