Cu或Ag氧化物对碱性沸石上对二甲苯与甲醇侧链烷基化反应的影响

INFLUENCE OF Cu OR Ag OXIDE ON THE SIDE-CHAIN ALKYLATION OF p-XYLENE WITH METHANOL ON BASIC ZEOLITES

本文研究了对二甲苯与甲醇在Cu或Ag氧化物改性的碱金属离子沸石上的侧链烷基化反应。研究结果表明,在碱金属离子沸石上引入Cu或Ag氧化物,对侧链烷基化初活性有明显的促进作用。研究还表明,在反应条件下Cu或Ag氧化物中的Cu或Ag元素以还原态存在,它们对反应的助催化作用不是由于调变了催化剂的酸碱性,而是还原态Cu°或Ag°使甲醇脱氢成为甲醛。

The side-chain alkylation of p-xylene with methanol on alkali cation exchanged and impregnated zeolites modified by Cu or Ag oxide has been studied. The results show that the introduction of Cu or Ag oxide greatly increases the initial activity of basic zeolites for side-chain alkylation. It is shown by ESCA that Cu or Ag oxide in the catalysts has been reduced into Co^0 or Ag^0 under the reaction conditions. No change of acid-base properties of the catalysts are observed after modification of the zeolites. In fact, the Cu^0 or Ag^0 catalyzes the dehydrogenation of methanol into formaldehyde, and therefore, they has a promoting effect on side-chain alkylation.