Research On Ru/TiO₂-lactate Catalyzed By Phenolic Resin Microspheres Catalysts For The Hydrogenation Of Ethyl

As one of important industrial chemicals,1,2-propanediol?1,2-PDO?has been widely applied in chemical industry.It is mainly used for producing all kinds of unsaturated polyester resin which is widely used.At present,the main method for the synthesis of 1,2-PDO is prepared with propylene oxide direct hydration under high temperature and high pressure.This method are not satisfied in the industry in terms of cost or environmental requirements.Therefore,the development of a conducive environment and raw materials and low cost of preparation of 1,2-PDO technology to replace the preparing process to propylene oxide as raw materials has important significance.It is a green route of selecting lactic acid or lactic acid esters as raw materials to prepare 1,2-PDO hydrogenation.At present,The literature shows that the hydrogenation reaction of lactic acid and lactic acid ester are in high temperature and high pressure conditions in the past.The key to make lactic acid or lactic acid ester hydrogenation to produce 1,2-PDO under mild conditions is to develop an efficient catalyst.Noble metal catalysts have been successfully used in many reaction system,it shows a good catalytic properties,which make it possible for the lactic acid or lactic acid ester hydrogenation under mild conditions.In this dissertation,Polymer microspheres is a good carrier supported catalyst with great active area.The noble metal as the active ingredient is dispersed and fixed on the surface of polymer microspheres carrier,can save the amount of precious metals,and can keep high catalytic activity of the catalyst.Nano-titanium dioxide because of its unique structure it has some unique surface properties?such as surface charge,etc.?,other rooms with precious metals also have some strong interaction.The use of nano-titanium dioxide modifications can be further improved carrier catalytic activity.Noble metal Ru with high activity of lactic acid ester carbonyl hydrogenation,dispersing the load on the surface of carrier can improve the efficiency of the catalytic hydrogenation of lactic acid ester.This paper have obtained phenolic resin based polymer microspheres carrier with improved hydrothermal method,and use nano titanium dioxide prepared by tetrabutyl titanate to modify the prepared phenolic resin based polymer microspheres,impregnation supported noble metal Ru to prepare the model supported Ru catalysts,using the prepared model supported Ru catalysts lactic acid catalysts for hydrogenation of ethyl 1,2-PDO glycol;Using XRD,SEM,TEM,FTIR,SEM-EDS and modern testing technology for phenolic resin based polymer microspheres and Ru/TiO₂-phenolicresinmicrospherescatalystcomposition,structureand microstructure,Using gas chromatography of ethyl lactate conversion rate and product selectivity of 1,2-PDO glycol were analyzed.Effect of reaction temperature,reaction time,hydrogen pressure,Ru loading,reaction solvent,substrate concentration on the lactate catalyzed by Ru/TiO₂-phenolic resin microspheres ester hydrogenation catalyst,Better optimized hydrogenation conditions Ru/TiO₂-phenolic resin microspherescatalytic hydrogenation of ethyl lactate.Paper also discusses the different methods for preparation of nanometer titanium dioxide,titanium different source and hydrolysis of titanium dioxide prepared catalyst preparation Ru/TiO₂-phenolic resin microspheres effect on catalytic hydrogenation of ethyl lactate.The main ideas of this paper are as follows:?1?With resorcinol and formaldehyde as raw materials,phenolic resin based polymer microspheres were synthesized by hydrothermal synthesis method of.Characterization results show that the spherical degree is high,the preparation of microspheres are functional,smooth surface,good monodispersity,low degree of reunion,microspheres particle size is about 0.8 microns.?2?The phenolic resin microspheres were modified by TiO₂,and takes it as the carrier,by the impregnation method supported noble metal Ru catalyst prepared Ru/TiO₂-phenolic resin microspheres.The characterization results show that,Ru/TiO₂-phenolic resin microspheres prepared catalyst was amorphous,which has a good sphericity,Ru and TiO₂ were uniformly dispersed on the surface of phenolic resin microspheres.?3?Ru/TiO₂-phenolic resin microspheres was optimized lactic acid ethyl ester hydrogenation catalyst preparation of 1,2-PDO better hydrogenation process conditions:Reaction temperature is 150?,filling the hydrogen pressure of 5 Mpa,the reaction time is 6 h,Ru capacity is 5%,reaction solvent is water,the molar ratio of reaction substrates and Ru for 100:1.?4?In the optimum hydrogenation conditions,Ru/TiO₂-phenolic resin microspheres the ethyl lactate catalyzed hydrogenation reaction of ethyl lactate conversion rate reached 82.3%,higher than that of Ru/phenolic resin microspheres the ethyl lactate catalyzed hydrogenation reaction of ethyl lactate conversion rate?71.3%?,and the selectivity of product will not be affected,all maintained at about 98%.?5?Effect of titanium,titanium dioxide preparation method on the Ru/TiO₂-phenolic resin microsphere catalyst in the catalytic hydrogenation of ethyl lactate in activity.Results show that with butyl titanate as titanium source,hydrolysis of nanometer titanium dioxide modified phenolic resin microspheres prepared by the carrier of the preparation of catalysts in the catalytic hydrogenation of ethyl lactate has higher catalytic activity.