关键词: Y型分子筛, 酸性, Bambenger重排, 对氨基苯酚, 选择性

Abstract:

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.

Key words: Y zeolite, Acidity, Bambenger rearrangement, p-Aminophenol, Selective