Catalyst of preparing pyrocatechol and hydroquinone in phenol hydroxylation

Abstract

The invention relates to a catalyst of preparing benzenediol in a phenol hydroxylation and a preparation technology thereof. The catalyst contains Fe2O3, ferro compound and zero valent ferri. The catalyst can transform phenol into the pyrocatechol and the hydroquinone in water containing oxyful in 0.5h (comprising about 25min of induction period) under the condition that the proportion of H2O2 to phenol is 1:1 and the temperature is 60 DEG C with the result that the transformation ratio of the phenol can reach 28 percent, the yield of the benzenediol reaches 25.5 percent, and the proportion of the pyrocatechol to the hydroquinone is about 1.3. When the proportion of H2O2 to phenol is 1.5:1, the transformation ratio of the phenol can reach 44 percent, and the yield of the benzenediol reaches 38.8 percent. The catalyst has low cost, simple preparation and stable performance. The catalyst is remarkably characterized by achieving the transformation ratio of the phenol from 0 to 28 percent within less than 2min of reaction, having higher activity and effectively reducing the side reaction.

Description

technical field [0001] The invention relates to a catalyst for preparing quinone by hydroxylation of phenol and its preparation technology, especially the composition of the catalyst. technical background [0002] In the 1980s, Enichem first successfully developed titanium-silicon molecular sieve (TS-1) [1] as a catalyst for the hydroxylation of phenol to quinone. 2 o 2 The conversion rate of phenol is 3:1, the conversion rate of phenol is 25% after 5 hours of reaction, the selectivity of hydroquinone reaches 90%, and the ratio of catechol:hydroquinone is 1:1. This process is currently internationally recognized as a model of green chemical industry, but the synthesis of TS-1 catalyst is complicated, expensive, slow in reaction and cumbersome in operation[2-3]. The overall performance of various other phenol hydroxylation catalysts [4-7] is difficult to compare with that of titanium silicon molecular sieve (TS-1). [0003] The catalyst involved in the present invention re...

AI Technical Summary

Problems solved by technology

This process is currently internationally recognized as a model of green chemical industry, but the synthesis of TS-1 catalyst is complicated, expensive, slow in reaction and cumbersome in operation[2-3]

The overall performance of various other phenol hydroxylation catalysts [4-7] is difficult to compare with that of titanium silicon molecular sieve (TS-1).