采用水热合成法制备了NaY分子筛,经离子交换和水热处理制得HY、USY和Ce-USY.研究了不同类型的Y分子筛对催化苯基羟胺重排合成对氨基苯酚的影响.XRD、N2吸附和Py-FTIR表征结果表明,此系分子筛虽然结晶性有差异,但均具有Y型分子筛的骨架拓扑结构.HY分子筛微孔孔径约为0.58 nm.NaY分子筛几乎无B酸中心.对其他3种分子筛而言,B酸量大小为:H Y＞USY≈Ce-USY;L酸量大小为:USY≈Ce-USY＞ HY.催化反应结果表明,Y型分子筛在此反应中表现出较差的效果,目标产物对氨基苯酚选择性和收率均低于15.00％.可见分子筛需维持酸性和孔径大小恰当时,才能使用最少的原料得到收率和纯度都较高的对氨基苯酚.%Different NaY molecular sieves,including NaY,HY,USY and Ce-USY,were prepared by in-situ hydrothermal process,ion exchange and/or hydrothermal treatment.The effects of isologous Y molecular sieves on p-aminophenol preparation from phenyl-hydroxylamine rearrangement were studied.XRD,N2 adsorption-desorption and Py-FTIR results showed that although the molecular sieves had differences in crystallinity,they all had the skeleton topology of Y type molecular sieves.The micropore size of HY molecular sieve was about 0.58 nm.NaY molecular sieve had almost no B acid site.For three kinds of other molecular sieves,B acid content ranked in the descending sequence:HY＞USY≈Ce-USY,and L acid content ranked in the descending sequence:USY≈Ce-USY＞ HY.The performance of their catalysts showed that Y-type molecular sieve had the inferior performance,the selectivity and yield of p-aminophenol of target product were less than 15％.So the p-aminophenol product with high yield and purity could be prepared from the smallest amount of reactant only when molecular sieve maintained an appropriate amount of acidity and pore size.
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