Thermodynamic parameters of carbofuran adsorption on pyrite were determined from experimental data. In order to minimize the dissolution of pyrite as well the degradation of carbofuran, all experiments were restricted to (15 to 20) min. The maximum adsorption capacity of carbofuran varied with both pH and temperature in the order: [Gamma(max)(carb)](pH 1.77) > [Gamma(max)(carb)](pH 2.70) > [Gamma(max)(carb)](pH 4.01). The Dubinin-Radushkevick (D-R) model was used to assess the degree of site heterogeneity. The interactions between carbofuran and surface sites can largely be ascribed to specific chemical interactions. (C) 2012 Elsevier Ltd. All rights reserved.