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采用浸渍法和离子交换法 ,制备出一系列改性 β沸石催化剂 ,考察了改性剂对 β沸石表面酸性及丙烯水合醚化反应性能的影响。结果表明 ,硼、锌、铝改性可以提高 β沸石的L酸中心 ,磷、镧、铈改性后 β沸石的B酸中心增加。催化剂的B酸和L酸中心与丙烯转化率和异丙醚选择性之间存在着一定的对应关系 :B酸量增加有利于提高丙烯转化率 ,L酸量增加有利于提高异丙醚的选择性。合适的B L酸比例是催化剂同时具有高活性和高异丙醚选择性的关键
A series of modified zeolite beta catalysts were prepared by impregnation method and ion exchange method. The effects of modifiers on the surface acidity of β zeolite and the hydration etherification of propylene were investigated. The results showed that the modification of boron, zinc and aluminum can improve the L acid center of β zeolite. The B acid center of β zeolite after phosphorus, lanthanum and cerium modification is increased. There is a certain relationship between the B acid and the L acid center of the catalyst and the conversion of propylene and the selectivity of isopropyl ether: Increasing the acid amount of B helps to improve the conversion of propylene, and increasing the amount of L acid is conducive to increasing the choice of isopropyl ether Sex. The proper B L acid ratio is the key to the catalyst’s high activity and high selectivity to diisopropyl ether