Mixtures of heavy aromatics with high aliphatics are important in the formation of asphaltenes in the oil industry. This work reports binary solid-liquid equilibria for naphtalene + eicosane, + pentacosane, + hexatriacontane mixtures by differential scanning calorimetry. Results are compared with those from modified UNIFAC (Larsen and Gmehling versions) and ideal predictions. Finally, we determine the purity according to van't Hoff equation. Results are in good agreement with values given by ultraviolet spectrophotometry. (c) 2006 Elsevier B.V. All rights reserved.