The extraction of levulinic acid by tricaprylmethylammonium chloride (Aliquat 336) dissolved in five alcohols solvents (isoamyl alcohol, hexan-1-ol, octan-1-ol, nonan-1-ol, decan-1-ol) and five esters solvents (dimethyl phthalate, dimethyl adipate, dimethyl succinate, dimethyl glutarate, diethyl carbonate), two ketones (diisobutyl ketone (DIBK), methyl isobutyl ketone (MIBK)) were investigated to understand effect of modifier on levulinic acid extraction. In addition to these Aliquat 336 + modifier system, the experiments were done also with single solvents. All measurements were carried out T = 298.15 K. Organic solutions of Aliquat 336 are being used increasingly to separate organic acids from aqueous mixture solutions by reactive extraction. The extent to which the organic phase may be loaded with levulinic acid is explained as a loading ratio, Z(Z). extraction efficiency E and, distribution coefficients K-D were calculated. The maximum extraction efficiency was obtained value of 72.1 for isoamyl alcohol. The extraction equilibrium constant, K-E, has been calculated for each modifier. Furthermore, Freundlich, Langmuir, and LSER model equations have been obtained for experimental data of alcohols. (C) 2009 Elsevier Ltd. All rights reserved.