新型甲苯择形歧化催化剂工艺条件优化

Optimization of Conditions for Toluene Disproportionation over a Novel Shape Selective Catalyst

以纯甲苯为原料,分别考察了温度、压力、空速和氢烃比等工艺条件对新型甲苯择形歧化催化剂性能的影响。结果表明:在新型甲苯择形歧化催化剂作用下,反应温度提高或反应压力增加,甲苯转化率增加,对二甲苯选择性下降;反应空速提高,甲苯转化率降低,对二甲苯选择性增加;氢烃比增加,甲苯转化率降低,对二甲苯选择性没有明显的变化。该催化剂稳定性良好,在反应温度445℃,压力2.0 MPa,氢烃分子比2.0和空速4.0 h^(-1)的条件下进行1 000 h催化剂稳定性试验,甲苯转化率可达30.2%,对二甲苯选择性可达94.3%。

The effects of temperature, pressure, space velocity and ratio of hydrogen to hydrocarbon on toluene disproportionation over a novel shape selective catalyst were investigated using pure toluene as feed. The results showed that the conversion of toluene increased while the selectivity of p-xylene decreased with the increase of the reaction temperature or reaction pressure. The conversion of toluene decreased while the selectivity of p-xylene increased with the increase of space velocity; the conversion of toluene decreased and the selectivity of p-xylene did not change obviously with the increase of molar ratio of H2 to hydrocarbon. Under optimized conditions of 445℃, 2.0 MPa, space velocity 4. 0 h-1 and molar ratio of hydrogen to hydrocarbon 2. 0, the stability of the catalyst was carried out. After reaction 1 000 h, the catalyst performance was very stable, and the conversion of toluene and the selectivity of p-xylene reached 30.2% and 94.3%, respectively.