Preparation Of Aldehyde Hydrogenation Trimethylolpropane

Trimethylolpropane is an important chemical intermediate and an fine chemicalproduct, mainly used for the production of alkyd resins and polyurethanes and can beused to produce high-grade paint, rosin esters, surfactants, fiber processing agents,plasticizers and advanced lubricants. In recent years, the study of their synthesis hasbeen widespread concerned，there are Connizarro and hydrogenation method, becauseduring the reaction of sodium hydroxide and other alkaline substances as a catalyst,the traditional method of Connizarro will generate a lot of formate, leading todistillation purification particularly difficult and increaseing energyconsumption.Aldehyde hydrogenation catalyst reduction is divided into two steps:first step, with alkaline catalyst, formaldehyde and butyraldehyde as raw materials,synthesize intermediate2,2-dihydroxy methyl butyl aldehyde; The second step, theintermediate2,2-dihydroxy methyl butyl aldehyde go on react to formtrimethylolpropane(TMP) in the autoclave, with hydrogenation catalyst byhydrogenation. Study some factors to make sure if they affect the intermediate2,2-dihydroxy methyl butyl aldehyde yield, and ultimately influence TMP yield, suchas the reaction temperature, amount of catalyst, the reaction of formaldehyde andbutyraldehyde molar ratio. We also consider the different hydrogen pressure, reactiontemperature, reaction time and hydrogenation catalyst, and from TMP yield todetermine the best reaction conditions of preparation of TMP.Having determined theoptimum reaction conditions for hydrogenation reaction mechanism, investigate andstudy some basic hydrogenation catalyst, such as palladium-carbon, ruthenium-carbon,Raney nickel and other precious metal hydrogenation catalytic performance, access torelevant literature, the main use of impregnation, coprecipitation and physicalmethods such as ultrasonic vibration catalysts prepared in different ways. Becausehydrogenation reactions usually react on the catalyst surface, so increase reactants andcatalyst contact area, and use SiO2, Al2O3, ZSM-5, MCM-41and SBA-15molecularsieve as a carrier material prepared by different of copper, nickel and other catalysts,through experiments, freshly prepare catalyst selectivity better than conventional catalysts, the yield higher. Compare copper catalyst and nickel catalyst, the catalyticeffect of copper are better. Different metal loading, indicate the catalytic effect of20%copper catalytic effect is best, and by XRD, BET, FTIR and other means the featureare evaluated.