Biosorption of 2,4-dichlorophenoxyacetic acid pesticide on powdered peach and apricot stones

The purpose of this work is to analyze the potential of two lignocellulosic wastes, namely peach and apricots stones, to adsorb 2,4-dichlorophenoxyacetic acid (2,4-D) pesticide from an aqueous solution. Both equilibrium and kinetic adsorption tests were performed. The maximum adsorption capacity achieved was 41.5 mg g −1 at 50 °C. The fitting of the experimental results to several empirical equilibrium models was studied, being Langmuir model the one that best fitted the adsorption data for both adsorbents. The thermodynamic analyses confirmed that 2,4-D adsorption on both lignocellulosic wastes was endothermic, spontaneous, and of a physisorption nature. For the kinetic study, the effects of multiple factors were examined including initial pH, adsorption temperature, 2,4-D initial concentration, and adsorbent dose. The results support the feasible use of these wastes as adsorbents in water treatment applications. Graphical abstract