Multi responses optimization of decarboxylation process of Free Fatty Acid (FFA) into biodiesel using Grey Relational Analysis (GRA)

Abstract

Grey Relational Analyses (GRA) was utilized to determine optimal setting parameters of Free Fatty Acid (FFA) conversion from into hydrocarbon chain by decarboxylation process. The considered setting parameters were voltage and acetic acid (CH3COOH) concentration. Decarboxylation process occurred by adding acetic acid as the ion contributor for the dimerization process. In order to facilitate FFA well ionized, electrolysis was employed during the decarboxylation with voltage varied from 10 Volt to 25 Volt. The concentration of Acetic Acid varied from 0.5M to 1.5M for an optimum condition with a high yield. Decarboxylation reaction took place at 130°C for 1 hour. The experiments were carried out by using full factorial design and multi responses considering % Yield, specific gravity (spgr), °API, viscosity, and Net Heating Value (NHV). Grey Reasoning Grade (GRG) was used to analysis multi responses. The setting parameters of sequence seven (A2 B3) has the highest GRG. Analysis of variance (ANOVA) results indicated that acetic acid concentration was contributing parameter. The optimal level for acetic acid concentration based on polynomial regression model was found to be 1.325 M.