Preparation And Catalytic Performance Of Mesoporous Ti Sieve Catalysts For The Synthesis Of N-Methyl Ethyl Alcohol

N-methyl ethanolamine products is a kind of important fine chemical product,which are widely used in chemical and petrochemical enterprises of the desulfurization agent,production of pharmaceutical intermediates.In terms of energy development and environmental protection,N-methyl aminoethanol series products have an irreplaceable position.Therefore,it is of great significance to optimize the process conditions,improve the process conditions and enhance the quality of N-methyl aminoethanol products.This paper focuses on the research of epoxy ethane and dimethylamine ring-opening to produce N-monomethylethanolamine corresponding products in the presence of catalyst.The effect of reaction temperature,pressure,molar ratio and substrate were investigated on the reaction.Through the screening of a series of catalysts,the mesoporous solid acid catalyst Ti-MCM-41 was obtained.At the same time,the reusable ability and reaction process of N-methyl alcohol amine are investigated and discussed,and also reaction mechanism is proposed.The main conclusions are as follows:1.A series of Ti-MCM-41 molecular sieve catalysts were prepared by hydrothermal synthesis method,and the characteristics and properties of the catalysts were studied.The catalyst was analyzed by XRD,BET,SEM,TEM,FT-IR and DR UV-vis characterizations.It could be found that the particle size of Ti-MCM-41 can be distributed in the 20⁴0nm,which has the characteristics of high specific surface and large size.At the same time,the Ti was found to be in the framework of catalyst in the presence of the four ligand and enriched catalyst surface acidity.In addition,a series of Ti-MCM-41 molecular sieves with different structures were obtained by adjusting the ratio of Si/Ti and calcination temperature.2.DMEA?N,N-dimethyl ethanolamine?was prepared by using the method of ethylene oxide with the mesoporous Ti-MCM-41 molecular sieve as catalyst and the influence of Si/Ti ratio and calcination temperature on the reaction were studied.It can be found that the catalyst prepared by the calcination temperature of 550 ^oC is the best catalyst for Si/Ti=5.The best yield of DMEA was 85.3%at the optimum conditions as followed:the time is 40 min,the reaction temperature and pressure are 145 ^oC and 2.5MPa,and the feeding ratio of epoxy ethane:dimethylamine=1:3.5.The catalyst has a good catalytic effect and has no change in structure and property after 5 times.3.The reaction of epoxide derivatives and organic amine catalyzed by Ti-MCM-41 was systematic investigated.It could be found that simple structure of aliphatic epoxides and organic amine has higher catalytic effect and the highest yield can reach 90.17%.For aromatic and heterocyclic structure of epoxy derivative and amine compounds showed a moderate catalytic effect with a maximum yield of 69.03%.It indicated that Ti-MCM-41 zeolite catalyst had good application prospects in the synthesis of?-amine alcohols.It could be found that the reaction is affected greatly by the acid sites of Ti-MCM-41 through NH₃-TPD characterization.At the same time,the mechanism of open-ring N-alkylation to synthesize DMEA catalyzed by Ti-MCM-41 was explored and the possible reaction process was shown.