15 Energy 46 132 139 2012 (original) (raw)

Homogeneous Catalysis of High Free Fatty Acid Waste Cooking Oil to Fatty Acid Methyl Esters (Biodiesel)

The waste cooking oil (WCO) is a promising feed stock for the synthesis of biodiesel. In this study, the WCO used for biodiesel production has a very high acid value (>13 mg KOH/g) so a simple base transesterification process was not suitable, which resulted in soap formation. Here we reported a two step process for biodiesel production from WCO, acid catalyzed esterification followed by base catalyzed transesterification. In the first step, the acid value of WCO was reduced below 1 mg KOH/g by homogeneous acid catalysis and in the second step, acid catalyzed WCO was transformed to biodiesel in the presence of NaOH as homogeneous base catalyst. GC/MS analysis was done to determine the chemical composition of WCO biodiesel. Five FAMEs, methyl dodecanoate (C12:0), methyl tetradecanoate (C14:0), methyl hexadecanoate (C16:0), methyl octadecanoate (C18:0) and methyl 9-octadecenoate (C18:1) were identified. The synthesized FAMEs were confirmed by FTIR and NMR (1H and 13C). The 1H NMR was also used to determine the percentage conversion of triglyceride to methyl esters which was 97.89%. The prepared biodiesel was investigated for fuel properties using ASTM standards methods.

Effect of reaction conditions in the catalytic esterification of palm fatty acid distillate to produce fatty acid methyl ester

Journal of Physics: Conference Series, 2019

Biodiesel or fatty acid methyl ester (FAME) obtained via esterification process is an alternative for industrial and transportation fuel. In this study, chromium-titanium mixed oxides catalyst synthesized via sol-gel method was used to catalyse the esterification of palm fatty acid distillate (PFAD) to produce FAME. Esterification was conducted in a batch reactor. The effects of reaction temperature, methanol to PFAD molar ratio, reaction time and reusability of catalyst were studied. Reaction conditions yielding the best performance of 89% FAME content were reaction temperature of 160°C, methanol to PFAD molar ratio of 3:1 and reaction time of 3 h. The catalyst can be reused for 3 times with 20% performance reduction between the first run and the third run. The results revealed that the mixed oxides of Cr-Ti is a potential heterogeneous catalyst for use in the esterification of high acid value feedstock of PFAD.