Sintesis Metil Oleat dengan Menggunakan Katalis H2SO4 dan Alat Pendispersi Homogen pada Suhu Ruang

Abstract

Synthesis of methyl oleate from esterification of oleic acid with methanol using H2SO4 catalyst and homogeneous dispersing apparatus at room temperature has been carried out based on three parameters, namely, the molar ratio of oleic acid : methanol, catalyst concentration, and rotational speed. The reaction conditions were carried out on the parameters of the molar ratio of oleic acid : methanol 1:6, 1:9, 1:12, catalyst concentration H2SO4 0,1; 0,2; 0,3; 0,5; 0,7 M, and rotational speeds of 3000, 4000, 5000 rpm. The conversion of methyl oleate that was monitored every 5, 15, 30, 45, 60, 75, 90 minutes was determined based on the change in acid number before and after the reaction based on SNI 7709:2012 and was confirmed again based on gas chromatography analysis and changes in its functional groups with an FT-IR spectrophotometer. Based on the three parameters that have been carried out, the maximum reaction conditions were obtained at the molar ratio of oleic acid : methanol (1:12), catalyst concentration of 0,7 M H2SO4, rotation speed of 4000 rpm, and reaction time of 60 minutes the conversion of methyl oleate reached 96,9 ± 0,1%, supported by the results of gas chromatography analysis of 97.2%, and analysis of changes in functional groups using an FT-IR spectrophotometer shows that there is absorption of -C=O stretching ester at wave number 1738.8 cm-1 and there is no stretching vibration of carboxylic acid -OH groups in the wave number area 3400-2400 cm-1 and supported by the characteristic stretching absorption band of the -C-O-C- group in the 1300-1000 cm-1 area where the absorption band with the smallest wave number on the right experiences a significant increase in absorption intensity. So that it can be concluded that there has been a process of substitution of the -CH3 group for the H atom of the -OH group of oleic acid.