TY - JOUR A1 - Brenneis, Rudolf A1 - Baeck, Burkhard A1 - Kley, Gerd T1 - Alcoholysis of waste fats with 2-ethyl-1-hexanol using Candida antarctica lipase A in large-scale tests N2 - Commercial native lipase A from Candida antarctica was used to produce alkyl esters through the alcoholysis of (waste) fats with 2-ethyl-1-hexanol. The process was carried out in batch stirred tank reactors (from 100 mL up to 3000 L). The content of alkyl esters in reaction mixtures was determined by gradient HPLC using an evaporative light scattering detector and the reaction progress was controlled by determining the ratio of the palmitic acid ester peak area to the oleic acid ester peak area in HPLC chromatograms. The results show that alcoholysis is the favoured reaction in presence of excess water and water-insoluble alcohols in comparison with hydrolysis (fatty acid content <5%). The optimum amount of water for the alcoholysis was found to be 80-100% of the amount of fat. In the presence of low quantities of water both alcoholysis and hydrolysis are slow. Conversion rate increases with increasing temperature to 65-70 °C. Based on these results a large-scale test to produce 3000 L of alkyl ester (to be used as lubricant coolant) was carried out. The experiments have proved that alcoholysis is completed after about 7-10 h depending on temperature. KW - Enzymatic alcoholysis KW - Candida antarctica lipase A KW - HPLC analysis KW - Ester oil KW - Large-scale test KW - Restaurant recycled grease PY - 2004 DO - https://doi.org/10.1002/ejlt.200401051 SN - 1438-7697 SN - 1438-9312 VL - 106 IS - 12 SP - 809 EP - 814 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-5222 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -