Preparation Of Rh-doped Mesoporous Materials And Application On Carbonylation Of Methyl Acetate

Vinyl acetate is a kind important chemical raw material,which can be used for the production of polyvinyl alcohol and other products.The traditional production methods of vinyl acetate are mainly acetylene and ethylene.China is limited by the resource structure of multiple coals and less oil,mostly by the acetylene method.Mainly,but acetylene pollution is heavy and energy consumption is high.The process for the production of vinyl acetate from the carbonylation of methyl acetate by Harkon,USA,has been decoupled from the traditional process,making full use of methyl acetate,which is of low industrial value,and using complexes such as ruthenium,palladium,and nickel as catalysts.It is of great significance to increase the utilization of resources and,on the other hand,to see the depletion of oil resources.From the current research status,the use of this method to produce vinyl acetate has achieved very good conversion rate and selectivity,and the reaction conditions are relatively mild,but mainly based on homogeneous catalytic systems,there are still difficult to separate products and catalysts Problems such as easy loss of catalyst active species and short catalyst life time have caused this method to be difficult to apply to industrial production at the current stage.Since these common problems of homogeneous catalytic systems are more difficult to solve,people gradually shift their focus to building corresponding The heterogeneous catalytic system aims to solve the above problems.The loading of the catalyst on the inorganic carrier is a common method of heterophasizing the homogeneous system,and the mesoporous material benefits from its good pore structure and structural characteristics.It is undoubtedly a hot topic for research workers.In the reaction of vinyl acetate in the production of polyvinyl alcohol,a large amount of methyl acetate by-products are generated.If a suitable high-efficiency catalyst can be found,a process route for the preparation of methyl acetate-vinyl acetate-polyvinyl alcohol,the by-product of the reaction,acetate is recycled into the cycle and is believed to be of great help to the relevant industrial applications of vinyl acetate.This paper attempts to use hydrothermal synthesis method to prepare mesoporous materials such as SBA-15,MCM-41 and SBA-16,and immobilize the ruthenium metal complexes with good performance in the homogeneous system on the inorganic skeleton of these materials.The reaction of ester carbonylation to produce vinyl acetate,using XRD,nitrogen adsorptiondesorption,SEM,TEM,FT-IR,NH3-TPD,etc.,to mesoporous SBA-15,MCM-41,SBA-16 materials before and after loading The characteristics of the crystals,pore structures,overall morphology,elements,and acidity of the materials were investigated.The reaction products were analyzed by gas chromatography and the reaction conversion and selectivity were calculated.Finally,it was found that the use of mesoporous materials such as SBA-15,MCM-41,SBA-16,etc.can well load Rh metal complexes,and the heterogeneous catalytic system built on this basis is very good in the carbonylation of methyl acetate.The performance of the catalyst increases the reuse rate of the catalyst while ensuring the conversion and selectivity,and makes the product easier to separate.