[en] Decomposition by ionizing radiations of two pesticides (Lannate and Fenvalerate) present in an aqueous solution has been studied on laboratory-scale experiments. The effect of pH of the solution, the concentration of the pesticide and the irradiation dose on the degradation process was investigated. Gamma-irradiation was carried out in air and in combination with nitrogen, oxygen and ozone. Lannate showed more degradation than Fenvalerate in all conditions investigated. Radiation was not enough to achieve the complete decomposition of the pesticides. Adsorption of the pollutants after irradiation was achieved using granular activated carbon (GAC) and two anion exchangers (Dowex 1-X8 and Lewatit AP 246). (author)

[en] The radiolysis of two basic dyes (Astrazon Red 6B and Astrazon Blue BG-200%), was investigated as a function of dye concentration, pH, irradiation dose and dose rate. It was found that the Astrazon Red 6B dye showed more radiation degradation than the Astrazon Blue BG-200% dye. Combining irradiation with the conventional treatment enhanced the degree of degradation. Addition of oxygen or hydrogen peroxide showed this enhancement, while nitrogen showed no change. A pH drop was observed and maybe attributed to the degradation of the dye molecules to lower molecular weight compounds such as organic acids. Experiments on the adsorption or exchange the dyes onto GAC, some polymeric ion exchange resins and polymeric membranes were carried out showing that GAC had the highest adsorption capacity. By combined treatment of irradiation and adsorption, the total removal of these toxic dyes was achieved. (author)

[en] Complete text of publication follows. The degradation kinetics due to irradiation of aqueous solutions of two acid dyes, namely Sandolane Milling N-Bl and Telon Fast Red and a basic dye (Sandocryl Blue B-3G) has been investigated. The factors affecting the radiolysis of the dyes such as dye concentration, irradiation dose, dose rate and pH of the solutions were studied. The effect of irradiation dose on various dye concentrations showed the complete destruction of the dyes at a dose of 4 kGy for low dye concentrations (20-50 mg/l), while at higher concentrations (100 mg/l) a dose of 20 kGy did not achieve the same effect. A combined treatment of the dye solutions by gamma irradiation and conventional methods showed that the saturation of these solutions did not enhance the degradation of the dyes. However, the addition of oxygen, hydrogen peroxide and sodium hypochlorite to the dye solutions coupled with γ-irradiation resulted in a remarkable enhancement in the degradation process and complete degradation of these pollutants was achieved using much lower doses of gamma radiation

[en] The graft copolymerization of Acrylamide onto polypropylene film using the direct gamma irradiation technique was studied. The factors affecting the grafting process such as type of solvent, inhibitor, radiation dose, and monomer concentration on the grafting yield were studied. It was found that the additions of 0.5 wt % , Mohr's salt reduced effectively the homo polymerization of acrylamide. The change in chemical structural of the pp-films due to grafting was investigated using IR, X-ray diffraction, thermal gravimeterical analysis, and scanning electron microscope (SEM). PP-g-p(AAm) films were allowed to react with two ionic dyes; organic reactive blue dye (Remazol Brilliant Bright Blue) and organic reactive red dye (Drimarene Scarlet K-2 G). The sshas been analyzed with visible spectrophotometry at 460 nm for dyed grafted film by red dye and at 490 nm for dyed grafted film by blue dye

[en] The degradation Kinetic due to irradiation of aqueous solutions of some commercial dyes, (Reactive Blue Brilliant, Reactive Yellow and Basic Blue 9 Dye (Methylene Blue 2 B), was studied. Factors affecting radiolysis of the dye such as dye concentration, irradiation dose, dose rate and ph of the solutions were studied. The effects of different additives such as nitrogen oxygen, hydrogen peroxide and sodium hypochlorite on the degradation process were investigated. The effect of irradiation dose on the different dye solutions at various concentrations, showed that the Reactive Yellow G. was very sensitive to gamma radiation. The effect of the ph of the dye solutions proved to very according type of the dye. Synergistic treatment of the dye solutions by irradiation and conventional method showed that saturation of the dye solutions with nitrogen did not enhance the radiation degradation of the dyes, while addition of oxygen resulted in a remarkable enhancement of the degradation of the dyes. Also, the addition of sodium hypochlorite (5%) and the oxidation by hydrogen peroxide resulted in more radiation degradation, Also, adsorption of the dyes onto Ga and some ion exchangers showed that Ga has the highest adsorption capacity. Radiation degradation of the toxic dye 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 conventional methods of purification alone

[en] The radiolysis of two basic dyes (Astrazon red 6b and Astrazon blue BG 200%), was investigated as a function of dye concentration, ph, irradiation dose and dose rate. It was found that the Astrazon red 6B dye showed more radiation degradation than that of the Astrazon blue BG-200% dye. Combining irradiation with the conventional treatment resulted in an enhancement in the degree of degradation. Addition of oxygen or hydrogen peroxide showed this enhancement, while nitrogen showed no change. A ph drop was observed and may be attributed to the degradation of the dye molecules to lower molecular weight compounds such as organic acids. The primary radiolysis products as the secondary products are responsible for the degradation of the dye chromophore. Experiments on the adsorption or exchange the dyes onto GAC, some polymeric ion exchange resins and polymeric membranes were carried out showing that GAC having the highest adsorption capacity. Through the combined treatment of irradiation and adsorption, the total removal of these toxic dyes was achieved

[en] Hydrogels have been prepared by Irradiation acrylic acid and glycerol using methanol and waster as solvents. Another sample was prepared with methanol only. The application of the prepared two hydrogels used for recovery of some reactive, acid and direct dyes and also recovery two different pesticides and detergents from wastewater were studies. The hydrogels complexes with different pollutants have been isolated and methanol and water as solvent during polymerization has a great adsorption towards dyes, pesticides and detergents than sample containing methanol only. The adsorption isotherm capacity of the two hydrogels was studies by the effect of temperature (20,30,40 degree) on the adsorption capacity through the kinetic studies of adsorption. The adsorption capacity increase with rising temperature and thermodynamic parameters Delta H, Delta S, and Delta G, were determined. Also the adsorption capacity is considerably affected by ph values (3,7 and 10). It was found that the adsorption capacity increases in acid medium and decreases towards the alkaline medium for both dyes and pesticides, while the irreversible results was shown in case of anionic detergents. Frundlich equation of adsorption isotherm was applied in this work

[en] Wastewater effluents from textile plants typically contain appreciable quantities of organic dyes that are resistant to degrade by ordinary treatment processes and constitute a highly visible form of pollution in the receiving waters. Carbon absorption as well as ionizing radiation are used as treatment processes. However, each method alone did not achieve the complete removal of these pollutants. A combined treatment is more effective. The two direct dyes(Direct orange S, Isma fast yellow Rl) were degraded by radiation 76% and 70% ,respectively. Also, the acid dye Sandolane Rubanole E-3 GSL (Acid red 37) was degraded almost to the same extent. Addition of O₂ or H₂O-2 resulted in a remarkable enhancement in the degradation process. The effect of ph, gamma-dose and dye concentration was studied. Polymeric ion exchangers proved to be more effective in the removal process than clays. However, granular activated carbon (GAC) was the best adsorbent for the direct dyes. Clays proved to be very good adsorbents for two basic dyes than their weak adsorption behavior of the direct ones

[en] Decomposition of two pesticides as active ingredient (Lannate and Fenvalarate) present in aqueous solution by ionizing radiations has been studied on laboratory-scale experiments. The effect of ph of the solution, the concentration of the pesticide and the irradiation dose on the degradation process was investigated carried out alone and in combination with other additives such as nitrogen, oxygen and ozone. A synergistic effect was detected which enhanced the degradation process remarkably. Lannate showed more degradation than Fenvalarte under conditions investigated. Radiation alone was not enough to achieve the complete decomposition of the pesticides. Adsorption of the un degraded pollutants was achieved using Granular Activated Carbon (GAC) and two anion exchangers (Dowex 1-X 8 and Lewatit AP 246) It may be concluded that irradiation followed by adsorption resulted in the removal of these organic pollutants from wastewater

[en] Membranes were prepared by the radiation-induced grafting of N-vinylpyrrolidone onto low density polyethylene and the possibility for their practical use in the removal of two dyes: Acid red 116(Erionyl red 2B) and blue reactive (Brilliant bright blue) was studied. The effect of the degree of grafting on the adsorption of these pollutants was investigated and showed maximum adsorption occurred at 394 % grafting. Radiation degradation of the dyes with a dose of ∼ 5 KGy was followed by adsorption of the residual concentration of the dyes by the membranes, which resulted in the complete removal of these pollutants as well as the radiolysis products present in the irradiated solutions. Also, characterization of the membranes before and after adsorption was carried out using thermogravimetric analysis and scanning electron microscopy