Separation of fumaric acid from aqueous media with tridodecyl amine (TDA), which is a long chain aliphatic amine, was carried out at 298 K. Different categories of diluents, ketones (methyl iso butyl ketone (MIBK), 2-heptanone, and 2-octanone) and alcohols (isoamyl alcohol, 1-octanol) and 1-decanoL) were used to dissolve TDA. Distribution coefficients (K-D), extraction efficiency (E), and loading factors (Z) were obtained as a function a experimental results. The most operative diluent was determined as heptan-2-one with the highest distribution coefffdent (KD) value of 26.00. In additional to experimental studies, the linear solvation energy relationship (LSER) modeling with included Hidebrand Hansen solubility parameters was applied for alcoholic diluents. Predicted data by LSER gave good agreement with experimental data.