A load of different PW/MCM-56 molecular sieve catalyst was got by the method of impregnation. The structure of the cat-alyst was characterized by X-ray diffraction(XRD)and NH3 chemical adsorption. In the homemade reaction device,MCM-56 molec-ular sieve catalytic activity of phosphotungstic acid load was validated on phenol and isopropanol alkylation reaction. Characteriza-tion results showed that phosphotungstic acid was commendable dispersed on the surface of zeolites HMCM-56 and acid strength in acid center was increased. Acid amount and acid strength were reduced in phosphotungstic acid of high load. The result showed that PW/MCM-56 molecular sieve catalyst activity was improved with the increase of load,under optimal reaction conditions of tempera-ture of 220℃,WHSV of 3 h-1 ,nPhenolIPA was molar ratio was 0. 8,the phenol conversion was highest under the load of 10%PW/MCM-56 molecular sieve catalyst,the total of selectivity O-isopropyl phenol and isopropyl phenol was close to 80%.%采用浸渍法制得了负载量不同的PW/MCM-56分子筛催化剂,并用X射线衍射(XRD)、NH3化学吸附表征了催化剂的结构,在自制反应装置上完成苯酚与异丙醇烷基化反应,以此评价负载磷钨酸的MCM-56分子筛的催化活性.表征结果显示,磷钨酸能很好地分散在HMCM-56分子筛的表面,强酸中心酸强度有所增加,过高的负载量降低酸量及酸强度.实验结果表明,PW/MCM-56分子筛催化剂活性随着负载量的增加有所提高,负载量为10%的PW/MCM-56分子筛催化剂上,在温度220℃,异丙醇与苯酚进料配比0.8,空速为3.0 h-1的条件下,苯酚转化率最高,对、邻异丙基苯酚总选择性接近80%.
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