Biodiesel production from transesterified yellow grease by ZSM-5 zeolite-supported BaO catalyst: process optimization by Taguchi's experimental design approach

Methanolysis of yellow grease (YG) was performed to synthesize its corresponding methyl ester (YGME) using BaO loaded on ZSM-5 (BaO/ZSM-5) as a heterogeneous base catalyst that was prepared via metallic solution hydrolysis method and characterized using N-2 adsorption-desorption (BET), surface basicity, XRD, TGA/DTA, SEM, FTIR and Raman techniques.### The Taguchi design approach was utilized to optimize the transesterification process factors, and among the parameters studied, calcination temperature was found to have a significant influence on YGME yield. At 70 degrees C for 3 h, a YGME yield of 95.9 +/- 0.94% was obtained using a methanol/YG molar ratio of 15:1 and 1 g (2 wt.% of YG used) of BaO/ZSM-5 sample calcined at 700 degrees C. The BaO/ ZSM-5 catalyst was reused six times with only a 15% decrease in activity.