Study On The Synthesis Of Carboxylic Esters By Br?nsted-Lewis Acidic Ionic Liquid

As an important fine organic chemical product,ester compounds were used widely in industry and daily life.In industry,acid alcohol esterification is often used to prepare ester compounds with H₂SO₄ as catalyst.For the strong acidity and strong oxidizing properties,H₂SO₄ has caused serious corrosion to production equipment,and also generated a large amount of waste water.To find environment-friendly catalyst is an important research in the current esterification reaction.As a new generation of green catalyst,ionic liquids（ILs）has the characteristics of structural design.In this study,a series of Br?nsted-Lewis acidic ILs were synthesized to increases the acidity of ILs,thus improving the catalytic performance.Firstly,the triethylamine Br?nsted-Lewis acidic ILs was synthesized and characterized.The acidity and corrosivity of the ILs was determined.The catalytic performance of the ILs was investigated by catalytic synthesis of n-butyl acetate.The yield of n-butyl acetate was 96.94%,and the ILs was could be used for 6 times.Secondly,the morphine Br?nsted-Lewis acidic ILs was synthesized and characterized.The acidity and corrosivity of ILs was determined.The catalytic performance of ILs was investigated by catalytic synthesis of ethyl octanoate.The conversion of octanoic acid was91.5%.The yield of ethyl octanoate was 89.6%,and ILs was highly active after the catalyst were used for 6 times.Finally,the caprolactam Br?nsted-Lewis acidic ILs was synthesized and characterized.The solubility,acidity and corrosivity of ILs were investigated.The catalytic activity of ILs was investigated by catalytic synthesis of n-butyl acetate.The Box-Behnken was used to optimize the esterification process.The yield of n-butyl acetate could reach 97.54%,and ILs was still highly active after repeated use of 6 times.