Hydrogenation suggested for upgrading fish oil biodiesel to commercial use.
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TBHQ addition to HYD FOME has lengthened the storage capacity.
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Selective hydrogenation has completely removed C20:5 and C22:6.
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Blended HYD FOME improved pour point and oxidation stability.
Abstract
Fish oil derived biodiesel has susceptibility to oxidation due to its higher polyunsaturated fatty acid content. Therefore, to control the rapid oxidation process, partial hydrogenation of fish oil biodiesel under 0.5 MPa pressure of H2 by using 0.5% Pd supported on Al2O3 spherical catalyst was done. It showed 8.0 h of oxidation stability after 1.0 h reaction higher than non‑hydrogenated fish oil biodiesel (0.1 h). A decrease in the rate of polyunsaturation (>95%) was achieved after 1.5 h of selective hydrogenation reaction with 17.3 h oxidation stability. Simultaneously, addition of antioxidants, such as3,5-di-tert-butyl-4-hydroxytoluene and tert-butylhydroquinone, to hydrogenated biodiesel was also performed to enhance its induction period more. Hydrogenated biodiesel was further blended with diesel to increase induction period and reduce the pour point. Thus, iodine value, viscosity, acid value and peroxide value of hydrogenated fish oil biodiesel met the EN 14214:2012 standard to be implemented as commercial automobile fuel.
