SAPO-11分子筛催化合成2,6-二甲基萘

摘要

以1,3,5-三甲苯(TMB)为溶剂,研究了萘与甲醇(ME)在SAPO-11分子筛催化剂上的烷基化反应,考察了原料配比、反应温度和空速对萘的转化率及2,6-二甲基萘(2,6-DMN)选择性的影响.实验结果表明,适宜的反应条件为∶n(萘)∶n(ME)∶n(TMB)=1.0∶5.0∶3.5,反应温度425 ℃,空速0.06 h-1.利用CuNO3对SAPO-11分子筛进行浸渍改性,采用BET和NH3-TPD方法对改性前后的SAPO-11分子筛的结构和酸性进行了表征.表征结果显示,改性后的SAPO-11分子筛的比表面积和孔体积减小,总酸量下降.随SAPO-11分子筛上Cu负载量的增加,2,6-DMN的选择性提高,萘的转化率降低.%The alkylation of naphthalene(NAPH) with methanol(ME) over SAPO-11 zeolite with 1, 3, 5-trimethylbenzene(TMB) as the solvent was investigated. The effects of the mole ratio of the reactants, reaction temperature and WHSV on the conversion of NAPH and the selectivity to 2, 6-dimethylnaphthalene(2, 6-DMN) were studied. The results indicate that the optimum reaction conditions are: 425 ℃, n(NAPH) : n(ME) : n(TMB) 1.0 : 5.0 : 3.5 and WHSV 0.06 h-1. The SAPO-11 was modified by impregnation with CuNO3 solution. The structures and acidities of the SAPO-11 before and after the modification were characterized by means of BET and NH3-TPD. The results showed that the specific surface area, pore volume and total acid amount of the SAPO-11 after the modification were decreased. The selectivity to 2, 6-DMN increased and the conversion of NAPH decreased with the increase of the Cu loading on the SAPO-11.