Carbon Nitride Supported Bimetal Catalyst For Tandem Hydroformylation-Hydrogenation Of Styrene

Alcohol is widely used as solvent and precursor of detergent.Unlike the multi-step process for alcohol production,tandem hydroformylation-hydrogenation can directly and selectively convert olefins into alcohols,which is an ideal process.In recent years,the development of tandem hydroformylation-hydrogenation has been made possible by the exploration of collaborative catalytic systems.At present,the reported collaborative catalytic systems are mainly homogeneous catalytic systems with two or more catalysts.Although the homogeneous catalytic system of collaborative catalysis has excellent catalytic performance,it is also faced with difficulties in separation from reactive solvent and low recyclability.Therefore,it is of great significance to explore heterogeneous catalytic systems with synergistic effects,especially single catalysts with bifunctional catalytic activity.In this thesis,graphite-like carbon nitride material（g-CN）was synthesized from urea raw material,and heterogeneous catalysts supported by g-CN bimetals were prepared and characterized.High catalytic activity and chemical selectivity were achieved in styrene series hydroformation-hydrogenation reaction,and it was found that this was due to the synergistic effect of bimetals in the series hydroformation-hydrogenation reaction.The effects of metal loading,reaction solvent,temperature and time on catalytic activity and selectivity of alcohols were investigated.The specific research conclusions are as follows:（1）A series of g-CN supported Rh-Ru nanoparticles bimetallic heterogeneous catalysts（Rh-Ru/g-CN）were prepared by high temperature calcination and impregnation-chemical reduction.Rh-Ru/g-CN shows excellent catalytic activity under the best conditions,the conversion rate is up to 99.9%,the proportion of alcohol in the product is up to 80.7%,and it is easy to separate from the reaction products and solvents.（2）A series of g-CN supported Rh-Co nanoparticles bimetallic heterogeneous catalysts（Rh-Co/g-CN）were prepared by the same method.The conversion rate of Rh-Co/ g-CN is up to 99.9% under the best conditions,and the total selectivity of the product alcohols is up to87.8%.Moreover,Rh-Co/ g-CN is easy to separate from the reaction products and solvents.