| Summary: | 碩士 === 國立中興大學 === 化學工程學系所 === 101 === The thesis was to investgate esterification of 4-amino benzoic acid sodium salt (Ph(NH2)COONa) and 1-bromobutane(RBr) to synthesize 4-minobenzoic acid butyl ester by phase transfer catalyst and ionic liquid in solid-liquid System. The operating parameters included type of catalyst, amount of catalyst, type of ionic liquid, amount of ionic liquid, agitation speed, amount of water, amount of KOH, type of organic solvent, amount of organic reactants, salts effect, and temperature.
The results indicated tetrabutylammonium bromide(TBAB) had best catalytic effect, because it is with more stable characteristics in alkaline. The reaction can not be conducted without adding any catalysts and ionic liquid, when adding 0.3 mmol catalysts and ionic liquid the yield increases to 94.79%. When the agitation speed was 300rpm, the yield had a maximum, more than 300rpm due to the solution splashed on the sidewall. Adding a little water can compose omega phase to improve the yield. When adding 2.5 ml of water the yield was 6.08 times to that in anhydrous condition, adding water to 15 ml the yield declined due to system becoming liquid-liquid type. When 0.27 mmol of KOH was used, the yield was 2.97 times that without KOH. When using highly polar solvent such as methyl isobutyl keton (MIBK), there would be the best catalytic effect than toluene, which indicated that the level of solvent effect is one of factors in the catalytic reaction. In this experiment, using (Ph(NH2)COONa) as limiting reagent, excess organic reactants could enhance the concentration in organic phase, adding excess 1-bromobutane up to 8 times would have the highest yield.
In the kinetic part, catalytic intermediate and organic reactants reaction dominated to conduct in the interface between the organic and middle phase. The kinetic results were correlated by us -ln(1-Y)=kappt equation successfully, where kapp was the apparent reaction rate constant, and the activation energy was 11.79 kcal/mol.
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