Sintesis Metil Oleat dari Asam Oleat dan Metanol Pada Variasi Waktu Reaksi dan Kecepatan Pengadukan

Abstract

The synthesis of methyl oleate was carried out through the esterification reaction of oleic acid and methanol using a K₂O/Zeolite catalyst with a homogeneous dispersing stirrer to determine the optimal conditions for conversion and yield of methyl oleate at varying reaction times (5, 15, 30, 45, 60, and 75 minutes) and stirring speeds (3000, 4000, 5000, and 7000 rpm). The K₂O/Zeolite catalyst was prepared by impregnating calcium acetate onto zeolite, calcined at 500°C for 4 hours, and analyzed using FT-IR, XRF, XRD, and SEM-EDX, showing a composition of K₂O (9.02%), SiO₃ (15.95%), and Al₂O₃ (70.96%) and a shift in the FT-IR absorption peak at 995 cm⁻¹. Methyl oleate conversion was measured by alkalimetric titration and gas chromatography (GC) analysis, while functional group characteristics were analyzed by FT-IR. Optimal results showed a conversion of 99.14% ±0.12% and a yield of 88.3% ±2.93% at a molar ratio of 1:15, 12% catalyst (w/w), a reaction time of 45 minutes, and a stirring speed of 5000 rpm. GC analysis showed a methyl ester conversion of 70.58%, and FT-IR confirmed the formation of ester groups (C=O at 1734,3 cm⁻¹, C-O-C at 1237,02-1171,55 cm⁻¹) without the -OH group of carboxylic acid (3400–2400 cm⁻¹), indicating the substitution of the -CH₃ group on oleic acid.