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Electroless nickel plating technology is today more important a surface treatment technology, in industrial production has been widely used. Electroless nickel production over time , the bath will phosphite by-products such as the accumulation of decomposition , forming electroless nickel plating wastewater . Chemical nickel plating wastewater containing the main pollutants of the total nickel, total phosphorus and COD. In this paper, electrolysis - chemical precipitation - Power -Fenton method used in conjunction with methods for treating chemical nickel plating wastewater , recycling useful materials to remove contaminants. First, electrolytic nickel plating wastewater treatment , the operating parameters were studied , study of pH, current density, temperature , circulation and electrolytic nickel recovery time and COD removal effect . The results showed that consider the entire waste and resource recovery process , electrolysis should recover nickel as the main objective , the optimal operating parameters of pH = 9, the current density is 8.0mA · cm-2, the reaction temperature is 80 ℃, circulation, electrolysis 2h nickel recovery of 98.7%, COD removal rate was 61.91% , the H2PO2- all waste is oxidized . Then continue processing using chemical precipitation waste , waste removal of phosphorus , study two kinds of precipitant CaO and Fe2 (S04) 3 of the process parameters on HPO32-, PO43- and total P removal effect . The results showed that Fe2 (SO4) 3 of the treatment effect than CaO, the pH optimum precipitation conditions = 7, Fe / P molar ratio of 0.5 , temperature is 20 ℃, aging time of 6.5h, HPO32-, PO43 - and total P were respectively 98.6% , 99.99% and 99.48% , while the waste liquid has also been some degradation of COD . Finally electricity -Fenton method to remove liquid waste COD, results show that electric -Fenton method can effectively remove the chemical nickel plating wastewater COD, optimal parameters for the continuous dosing , pH = 3, the current density is 13.16 mA · cm -2, H2O2 dosage of theoretical demand , Fe2 / H2O2 molar ratio of 1/10, COD removal efficiency was 97.89% . Meanwhile, the remaining waste is oxidized HPO32- PO43-, PO43- and Fe3 precipitate is removed. The three-step treatment, waste of total nickel and total P concentrations reach the national emission concentration , COD was 305.52 mg · L-1, pH value of 3.01 , waste water quality has been greatly improved.
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