Use of an Adsorption Process for Purification of Pollock-Oil-Based Biodiesel Comprises Methyl Esters

The quality of biodiesel from crude pollock oil and the effect of a purification process on the physicochemical properties of pollock oil biodiesel were evaluated. Unpurified pollock oil (PO) was transesterified to biodiesel from pollock oil (BPO) using methyl alcohol (1:6 molar ratio) and NaOH (1 % w/w of the oil weight); and the resulting fatty acids methyl esters (FAME) were purified with 10 % (w/w) activated earth to yield purified biodiesel from pollock oil (PBPO). The samples were evaluated for yield, FAME composition, free fatty acids (FFA), peroxides value (PV), moisture, bulk density, cloud point, flash point, free and total glycerin, color, rheological properties, and minerals. BPO and PBPO were evaluated for the kinetics of lipid oxidation. The transesterification and purification processes had no effect on the FAME composition of PO. The yield of PBPO was significantly (P < 0.05) reduced after the transesterification and purification processes. Moreover, the transesterification process significantly (P < 0.05) reduced the FFA, moisture, bulk density, flash point, total glycerides, redness, viscosity, arsenic and silicon content in PO. Meanwhile, the purification process significantly (P < 0.05) reduced the PV, redness, and sulfur content of BPO. The flash point of BPO was significantly (P < 0.05) increased by the purification process from 79 to 84 A degrees C. PO, BPO, and PBPO behaved as non-Newtonian and Newtonian fluids at 0 and 25 A degrees C, respectively. BPO showed a lower oxidation rate and activation energy compared to those of PBPO. BPO and PBPO met the ASTM biodiesel standard D6751 for moisture, bulk density, cloud point, free and total glycerin, Na, P, and S. The study demonstrated that high viscosity crude pollock oil could be converted into low viscosity purified pollock oil biodiesel.