The usage of orange pulp activated carbon in the adsorption of 2,4-dichlorophenoxy acetic acid from aqueous solutions.

Among the numerous agrochemicals in use today, the herbicide 2,4-dichlorophenoxy acetic acid (2,4-D), has been widely applied to control broad-leaved weeds in gardens and farming. 2,4-D is commonly preferred because of its low cost and good selectivity. On the other hand, 2,4-D is a poorly biodegradable pollutant. Therefore, this study has focused on the adsorption of 2,4-D from aqueous solutions by using activated carbon. The activated carbon was produced from the orange ( L.) pulp by chemical activation with zinc chloride. The morphological and chemical characteristics of the activated carbon were investigated by infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N-adsorption techniques. Then, the effect of adsorption parameters was researched for 2,4-D adsorption on activated carbon. The experimental data indicated that the adsorption isotherms were well described by the Langmuir equilibrium isotherm equation and the calculated adsorption capacity was 71.94 mg g at 298 K. The adsorption kinetic of 2,4-D obeys the pseudo-second-order kinetic model. The thermodynamic parameters indicated a feasible, spontaneous and exothermic adsorption. These results show that the prepared activated carbon has good potential for the removal of 2,4-D from aqueous solutions.