Transesterification of palm oil in a microtube reactor

Abstract Transesterification of palm oil and methanol with KOH as a catalyst in biodiesel synthesis was studied in a microtube reactor. The first part is the investigation on the influences of catalyst amount (5–13 mg/g, 0.5–1.3 mass%), reaction temperature (52–70 °C), methanol‐to‐oil molar ratio (4.5:1–9:1), and residence time (5–20 s) on fatty acid methyl ester content (%FAME). The optimal %FAME of 97.14 % was achieved with the catalyst amount of 10 mg/g (1 mass%), operating at 60 °C, and using a methanol‐to‐oil molar ratio of 6:1 and a residence time of 5 s. High %FAME was obtained at low residence time due to the small size of droplets in the micro‐channel reactor. The second part deals with the effect of mixer and reactor geometry. A comparison between %FAME obtained from the synthesis in a batch stirred‐tank reactor and in a microtube suggested that the reaction proceeded much faster for the latter. The use of a T‐mixer provided superior reaction performance compared to the J‐mixer throughout the conditions studied.