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考察了分子筛的类型、硅铝比及Cu和Pd改性对分子筛催化剂上二甲醚低温水解活性的影响.结果表明,酸性的MCM-22和HZSM-5分子筛催化剂具有较高的二甲醚水解活性,且其活性随着分子筛硅铝比的增加而降低.这表明分子筛的类型及酸性对催化剂性能有重要影响,具有超笼结构的MCM-22分子筛上B酸中心的良好可接近性,使得该分子筛催化剂的水解活性较相同硅铝比的HZSM-5分子筛高.与改性前相比,Cu和Pd改性后的MCM-22催化剂显示出更高的二甲醚水解活性.
The effects of molecular sieve type, silica to alumina ratio and modification of Cu and Pd on the low temperature hydrolysis activity of dimethyl ether on molecular sieve catalysts were investigated. The results show that the acidic MCM-22 and HZSM-5 zeolites have higher dimethyl ether hydrolysis Activity, and its activity decreases with the increase of silica to alumina molecular sieve, indicating that the type and acidity of the molecular sieve have an important influence on the catalyst performance. The good accessibility of the B acid center on the MCM-22 molecular sieve with a supercaged structure makes The molecular sieve catalyst has higher hydrolytic activity than HZSM-5 molecular sieve with the same Si / Al ratio, and Cu and Pd modified MCM-22 catalysts show higher dimethyl ether hydrolysis activity than before modification.