Preparation Of Load Multielements Modified Photocatalysts And Research On Advanced Treatment For Coking Wastewater

Clay brick was used as a supporter, loaded Fe-Sm-Yb modified TiO2photocatalystswere prepared by dip-coating method, then the reuse of photocatalyst was realized. Theadvanced treatment of COD、chrominance and NH3-N in coking water were conductedby photocatalysis technology. Coking wastewater after processing reached the waterquality index of industrial circulating cooling water treatment design specification(GB50050-2007). And it can be reused as the industrial circulating cooling water.Different supporters were selected to prepare load multielements modifiedphotocatalysts, then the best supporter was confirmed for clay brick. Load multielementsmodified photocatalysts have a certain lifetime and fine firmness, they can be used inadvanced treatment of coking water. The influence factors of COD、NH3-N andchrominance degradation rates were discussed by single factor experiment. The optimumprocess conditions of pH neutral, photocatalyst charge of1.5g, illumination for6h,reaction at50℃, calcination at500℃were obtained. Orthogonal experiment results showthat COD degradation rates are45.68%, which are the highest in the conditions ofphotocatalyst charge of1.4g, illumination for6h, reaction at50℃, calcination at550℃.NH3-N degradation rates are82.23%, which are the highest in the conditions ofphotocatalyst charge of1.4g, illumination for6h, reaction at55℃, calcination at500℃.Chrominance degradation rates are78.65%, which are the highest in the conditions ofphotocatalyst charge of1.4g, illumination for6h, reaction at45℃, calcination at500℃.We expanded the wastewater quantity in Laboratory conditions. Dynamicexperiment was proceeded to find the optimum experiment conditions in homemadephotocatalytic reactor. Flocculation-photocatalytic method was adopted after contrastingthe treatment effect with flocculation method and photocatalytic method. The resultsshow that COD degradation rates are80.42%, NH3-N degradation rates are98.36%andchrominance degradation rates are86.84%are obtained in the optimum experimentconditions of photocatalyst charge of7.0g, illumination for9h.