Preparation Of Co-Supported Nitrogen-Doped Carbon Materials And Study On Catalytic Esterification Of Aldehydes

Ester is an important chemical intermediate.They are usually oxidized by aldehydeor alcohol to prepare acids or derivatives of acids,and ester is prepared by esterification.However,the process is complex and the energy consumption is high.Therefore,it is urgent to explore an efficient and environmentally friendly way for oxidition esterification of aldehydeor alcohol to ester.One step oxidative esterification of aldehydes and alcohols is a simple,clean and efficient green synthesis method.The activity performance and stability of catalyst are very important in the reaction process,which mainly depends on the design and preparation of catalyst.The cost limite the application of noble metal catalysts,non noble metal catalysts will be the key research direction in the field of aldehyde oxidative esterification in the future.Cobalt supported nitrogen doped catalysts have attracted more and more attention beacuse of the excellent catalytic performance.In this paper,we prepared two kinds of cobalt supported N-doped catalysts with different preparation methods,and investigated the catalytic performance of aldehyde oxidative esterification.The main research contents are as follows:1. A series of cobalt supported N-doped catalysts were synthesized.Manganese oxide,zinc oxide and carbon black?XC-72R?were used as supports,respectively.The catalysts were applied to the oxidative esterification of methylacrolein?MAL?and methanol?Me OH?.The influence of support on the catalytic performance was studied.XRD,BET,XPS,TEM and H₂-TPR were used to characterize the structure,properties and state of the catalyst.At the same time,Co@N/C catalyst was selected to investigate the single factor conditions of catalyst.calcination temperature,alcohol aldehyde ratio,catalyst concentration,reaction temperature and reaction pressure of the catalytic system were selected to explore the most suitable reaction conditions for Co@N/C catalyst to oxidative esterification of furful.2. A series of highly dispersed co supported N-doped ordered porous carbon catalysts?CO-NOPC?were synthesized for the oxidative esterification of furfural to 2-methyl furoate.The complex of cobalt chloride and 2,2'-bipyridine was filled into the channel of sacrificial template?MCM-41,ZSM-5,SBA-15 were used to synthesize Co-NOPC-M,Co-NOPC-S,Co-NOPC-Z respectively?.Because of the restriction of sacrificial template and the strong coordination between cobalt chloride and 2,2'-bipyridine ligand,highly dispersed cobalt based nitrogen doped ordered porous carbon materials were obtained.The catalysts were characterized by XRD,Raman,SEM,TEM,BET,ICP-MS and XPS.The results show that the catalytic performance of the catalyst is related to the highly dispersed,ordered mesoporous structure and specific surface area of cobalt.The reaction mechanism of the catalyst was put forward,and the stability of the catalyst was also tested.