Effect of Gamma Radiation in the Removal of some Hazardous Waste

The treatment of wastewaters containing toxic pesticides poses a serious environmental problem. Many of the pesticides are not readily biodegradable and complete removal in many cases is a relatively expensive process. Ionizing radiations proved to be more effective for the treatment of these wastewaters than ordinary conventional methods. In the present study a try was made to explain the degradation kinetic due to irradiation of aqueous solutions of some active ingredient pesticides.. These pesticides are: two Organophosphorous Pesticides; Dimethoate and Sumithion and one Organo chlorine Pesticide: DDT. A combined treatment of gamma irradiation and conventional methods was applied . Factors affecting the radiolysis of pesticides such as pesticide concentration, irradiation dose, dose rate and ph of the solutions were studied. The effect of different additives such as nitrogen and oxygen showed an enhancement in the degradation process. Experiments on the adsorption of pesticides on some polymeric materials and on Granular Activated Carbon (GAC), showed that GAC has degradation followed by adsorption of the toxic pesticide pollutants and their removal from wastewater down to concentrations not exceeding the maximum permissible concentration (MPC), according to international standards, proved to be better than the conventional methods of purification and more economical as well