超声浸渍无机盐改性Hβ分子筛催化合成乙基蒽醌

Synthesis of ethyl anthraquinone over Hβ zeolites modified with inorganic salts by ultrasonic impregnation

采用超声浸渍法将无机盐Al2(SO4)3、(NH4)2SO4、Ce(NH4)2(NO3)6和Fe(NO3)3负载于Hβ分子筛上,通过NH3-TPD、XRD和吡啶-IR对分子筛进行表征,考察改性前后分子筛酸性能和晶相的变化。将改性的Hβ分子筛用于催化乙苯和苯酐合成乙基蒽醌。结果表明,不同无机盐超声浸渍改性分子筛的催化效果差别较大,其中,每克分子筛负载0.2 g的Al2(SO4)3的Alβ分子筛催化效果最好,苯酐转化率为45.67%,乙基蒽醌选择性为50.12%。分子筛的酸性能(包括酸量、酸种类和酸强度)对催化性能影响较大。

Four kinds of new catalysts were prepared by loading inorganic salts including A12 （SOg）3, （NH4）2SO4 ,Ce（NH4 ）2 （NO3）6 and Fe（ NO3 ）3 on Hβ zeolite respectively by ultrasonic impregnation method. The acidic properties and crystal phase of as-prepared Hβ zeolites were characterized by means of NH3-TPD,XRD and Pyridine-IR. The modified Hβ zeolites were used to catalyze Friedel-Crafts reaction of ethyl benzene with phthalic anhydride to synthesize ethyl anthraquinone. The results indicated that modified H~ zeolites derived from different inorganic salts showed different catalytic capability. Among four modified Hβ zeolites, Alβ zeolite supported with A12 （ SO4 ） 3 [ 0.2 g- A1E （ SO4 ） 3 （g-zeolite） -x ] exhibited the best catalytic property,and phthalic anhydride conversion of 45.67% and the selectivity to ethyl anthraquinone of 50.12% over Al2 zeolite were attained. It was also found that the acidic properties of modified zeolites,including the amount, the type and the strength of acid, had obvious influence on the catalytic performance of the modified zeolites.