Adsorption of 2,4-Dcichlorophenoxyacetic Acid onto Microporous Activated Carbon Prepared From a Waste of Fruit Juice Industry by Chemical Activation

摘要

2,4-dichlorophenoxyacetic acid (2,4-D) is an extensively used herbicide throughout the world. Exposure of surface and ground water to 2,4-D leads to contamination, which consequently poses serious threat to humans and marine organisms. Hence, effective removal of this toxic herbicide from wastewaters using suitable adsorbents is coming into prominence. Several techniques have been used for the elimination of 2,4-D from contaminated waters such as photocatalytic degradation, conventional and advanced oxidation processes, aerobic degradation, coagulation/flocculation/sedimentation, ozonation, membrane filtration and adsorption [1]. Among such processes, adsorption has numerous advantages, including: applicability at very low concentrations, ease of operation, suitability for batch and continuous processes, and low capital cost. In the adsorption of organic species, activated carbon has been extremely successful due to its excellent adsorbent properties. In this study, a highly microporous activated carbon was prepared from a waste of fruit juice industry, pomegranate peel, by potassium carbonate activation for removal of 2,4-D from aqueous solutions. Batch adsorption studies were performed to investigate effects of different parameters such as initial pesticide concentration, contact time and temperature. To clarify the ability of carbon to remove the pesticides, adsorption capacity of 2,4-dichlorophenoxyacetic acid, was explored from the adsorption isotherms, kinetics and thermodynamics points of view.