TY - JOUR AB - The preparation of a variety of sulfonated carbons and their use in the esterification of oleic acid is reported. All sulfonated materials show some loss in activity associated with the leaching of active sites. Exhaustive leaching shows that a finite amount of activity is lost from the carbons in the form of colloids. Fully leached catalysts show no loss in activity upon recycling. The best catalysts; 1, 3, and 6; show initial TOFs of 0.07 s(-1), 0.05 s(-1), and 0.14 s(-1), respectively. These compare favorably with literature values. Significantly, the leachate solutions obtained from catalysts 1, 3, and 6, also show excellent esterification activity. The results of TEM and catalyst poisoning experiments on the leachate solutions associate the catalytic activity of these solutions with carbon colloids. This mechanism for leaching active sites from sulfonated carbons is previously unrecognized. (C) 2013 Elsevier Ltd. All rights reserved. AD - Wake Forest Univ, Dept Chem, Winston Salem, NC 27109 USA AN - WOS:000326660900080 AU - Deshmane, C. A. AU - Wright, M. W. AU - Lachgar, A. AU - Rohlfing, M. AU - Liu, Z. N. AU - Le, J. AU - Hanson, B. E. DA - Nov DO - 10.1016/j.biortech.2013.08.073 J2 - Bioresource Technol KW - esterification LA - English N1 - 247ym PY - 2013 SN - 0960-8524 SP - 597-604 ST - A comparative study of solid carbon acid catalysts for the esterification of free fatty acids for biodiesel production. Evidence for the leaching of colloidal carbon T2 - Bioresource Technology TI - A comparative study of solid carbon acid catalysts for the esterification of free fatty acids for biodiesel production. Evidence for the leaching of colloidal carbon UR - ://WOS:000326660900080 VL - 147 ID - 8616 ER -