Biodiesel production by esterification of palm fatty acid distillate

Production of fatty acid methyl ester (FAME) from palm fatty acid distillate (PFAD) having high free fatty acids (FFA) was investigated in this work. Batch esterifications of PFAD were carried out to study the influence of: including reaction temperatures of 70–100 1C, molar ratios of methanol to PFAD of 0.4:1–12:1, quantity of catalysts of 0–5.502% (wt of sulfuric acid/wt of PFAD) and reaction times of 15–240min. The optimum condition for the continuous esterification process (CSTR) was molar ratio of methanol to PFAD at 8:1 with 1.834wt% of H2SO4 at 70 1C under its own pressure with a retention time of 60min. The amount of FFA was reduced from 93wt% to less than 2wt% at the end of the esterification process. The FAME was purified by neutralization with 3M sodium hydroxide in water solution at a reaction temperature of 80 1C for 15min followed by transesterification process with 0.396M sodium hydroxide in methanol solution at a reaction temperature of 65 1C for 15min. The final FAME product met with the Thai biodiesel quality standard, and ASTM D6751-02. r 2007 Elsevier Ltd. All rights reserved.