Supercritical carbon dioxide-based integrated continuous extraction of oil from chicken feather meal, and its conversion to biodiesel in a packed-bed enzymatic reactor, at pilot scale

The continuous production of biodiesel (fatty acid methyl esters; FAME) from chicken feather meal (CFM) was carried out in supercritical carbon dioxide (sc-CO2), in a process combining extraction of oil from CFM followed by transesterification of the CFM oil with methanol. First, extraction experiments were carried out at different pressure, temperature and solvent flow rate conditions to assess the influence of these process parameters on the extraction rate and composition of extracted oil. Over 90% of the oil available in CFM was extracted by sc-CO2 in 60 min. Oleic acid (C18:1), palmitic acid (C16:0) and linoleic acid (C18:2) were the major components of the oil extracted, accounting for ca. 84% w/w. The integrated extraction and enzymatic transesterification of CFM oil was then carried out at 40 degrees C and 250 bar, at solvent flow rates in the range 30-150 g/min, for oil: methanol molar ratios of 1:6-1:24, using Lipozyme RM IM (R) as biocatalyst, in a pilot plant unit. The lowest FAME yield obtained was 96.7%. Both the extraction and reaction steps were modeled, based on a broken and intact cells approach and the consideration of three consecutive steps, respectively, and a good agreement with experimental data was obtained. (C) 2015 Elsevier Ltd. All rights reserved.