Preparation Of Modified MCM-41 Catalyst And Study On Its Catalytic Oxidation Of Benzyl Methanol To Benzaldehyde

Benzaldehyde is an important chemical intermediate.It is widely used in medicine,dyes,spices,medicine and other fields.At this stage,the demand for benzaldehyde is increasing year by year.How to simplify the benzaldehyde process,reduce secondary pollution and selective preparation of benzaldehyde has always been a breakthrough point in the oxidation of benzyl alcohol to benzaldehyde.In this paper,hexadecyltrimethoxyammonium bromide,ethyl orthosilicate and ammonia are used as raw materials to synthesize MCM-41mesoporous materials by hydrothermal crystallization method,and gradually use 3-chloropropyltrimethoxy,silane,creatinine,thallium nitrate were gradually used MCM-41 mesoporous materials,and modified with ligands such as cerium nitrate and cerium nitrate.MCM-41/creatinine/Ce and MCM-41/creatinine/Pr were successfully prepared.A series of characterizations were carried out by X-ray diffraction,Fourier infrared spectroscopy,differential pyrolysis thermogravimetric analysis,scanning electron microscopy,and energy spectroscopy.Two catalysts,MCM-41/creatinine/Ce and MCM-41/creatinine/Pr,were used in the selective oxidation of benzyl alcohol for the selective preparation of benzaldehyde,and a high-performance liquid chromatography was established.?Methanol?:V?H₂O?=40:60,the content of benzyl alcohol,benzaldehyde and benzoic acid is tested.Finally,the optimal reaction conditions and service life of the two catalysts for the oxidation of benzyl alcohol to benzaldehyde were investigated.The experimental results show that When using MCM-41/creatinine/Pr as a catalyst,the conversion rate of benzyl alcohol can be up to 77.29%,and the selectivity of benzaldehyde can reach 65%;In contrast,MCM-41/creatinine/Ce catalyst shows better catalytic activity,in which the conversion rate of benzyl alcohol can reach89.02%,the selectivity of benzaldehyde is 85%.