Biodiesel from extracted fat out of meat and bone meal

Nine non-halogenated solvents for the extraction of fat from meat and bone meal (MBM) were evaluated by the accelerated solvent method. Yields of about 15% were obtained with all solvents, but n-hexane was found to be the most suitable extraction solvent, because it is relatively cheap and has a low boiling point. Fat was also extracted from MBM on preparative scale (600 g) by immersion, and the extracted material was analysed for impurities that could affect the subsequent transesterification. The extracted material was converted into fatty acid methyl esters (FAME) via a two-step process. For further purification, the raw FAME were distilled under reduced pressure. The final product was analysed according to the European specification for biodiesel (EN 14214). Almost all of the values were within the specifications, except the cold-temperature behaviour and the oxidation stability. All in all, extracted fat from MBM is a potential feedstock for the production of biodiesel.