Reactions of grape marc with CO/H2O have been investigated over a range of temperatures (320-425 degrees C) with and without added sodium carbonate (Na2CO3) or sodium aluminate (NaAlO2) with a view to optimising liquid fuel quality. The quality of the product can be improved by raising the temperature and/or by addition of alkali, Na2CO3 or NaAlO2, which helped to decarboxylate/decompose fatty acids and lower the oxygen content. The energy recovery of the dichloromethane soluble products ranged from 50% to 75%. (C) 2015 Elsevier Ltd. All rights reserved.