金属改性多级孔TS-1催化环己烷直接合成环己酮肟

Direct synthesis of cyclohexanone oxime from cyclohexane over metal modified hierarchical TS-1

以环己烷直接制备环己酮肟是化学工业绿色和可持续化发展的理想方法之一。考察了多级孔TS-1及金属改性多级孔TS-1对环己烷、双氧水和氨水直接合成环己酮肟的催化活性,结合样品的紫外漫反射光谱,X射线电子能谱,N_(2)的等温吸附-脱附等表征,探究影响催化性能的因素。实验结果表明:多级孔TS-1中的多级孔有利于反应物和生成物迅速扩散,而Cu改性的多级孔TS-1中的Cu-O-Ti可选择性吸附并活化NH_(3),促进羟胺的原位生成,同时抑制环己酮肟进一步氧化。Cu含量为2.5%的催化剂催化活性最好,环己烷的转化率为15.3%,环己酮肟的选择性和产率分别为72.2%和11.0%。

The direct synthesis of cyclohexanone oxime from cyclohexane was one of the ideal methods for green and sustainable development in chemical industry.The catalytic activities of hierarchical TS-1 and metal hierarchical TS-1 for the direct synthesis of cyclohexanone oxime from cyclohexane,hydrogen peroxide and ammonia were investigated.To study the key factors during catalyzation,the samples were characterized by Ultraviolet-visible diffuse reflectance spectra,X-ray electron spectroscopy,N_(2) isothermal adsorption-desorption etc.The experimental results showed that the hierarchical composite pore in hierarchical TS-1 facilitated the rapid diffusion of reactants and products.Cu-O-Ti in Cu-modified hierarchical TS-1could selectively adsorb and activate NH_(3),promote the in-situ formation of the hydroxylamine,and inhibit the deep oxidation of cyclohexanone oxime.The catalyst with Cu 2.5%has the best catalytic activity,the conversion of cyclohexane was 15.3%,and the selectivity and yield of cyclohexanone oxime were 72.2%and 11.0%,respectively.