Pretreatment Of Electroless Nickel Plating Wastewater And Recovery Of Nickel In PCB Industry

Electroless nickel Plating is a kind of surface treatment in In today’s world which is widely used in industrial Production field. But during the Production Process electroless nickel Plating bath decomposed because of the accumulation of by-products such as HPO32-ions and became electroless nickel plating wastewater. The main Pollutants in electroless nickel plating wastewater were total nickel and total phosphorus.in this paper,we applied Electrolysis to treat eleetroless nickel plating baths, And recovery of useful substances. We use pulse-electrocoagulation to deal with electroless nickel plating rinse wastewater.Electrolysis was applied to treat the wastewater. The effects of pH, current density, temperature, electrolysis time,solution concentration and broken agent concentration on the recovery efficiency of nickel was studied by. The result showed the purpose of temperature should be the recovery of nickel considering the whole treating process of electroless nickel plating wastewater. Then we chose pH, current density, electrolysis time,solution concentration these four factors to do a the four factors three levels orthogonal experiment. The results show that the influence of these four factors on the recovery of nickel from large to small is the current intensity, electrolysis time, concentration and pH value. The best experimental condition is PH value:7; the current intensity:3 A/m2, the temperature:90℃, the electrolysis:3 hours,the concentration and the concentration of the breaker are 7g/L and lg/L. Under these conditions, the removal rate of Ni2+ was 97.03%.Electrolysis was applied to treat the wastewater. The effects of pH, current density, plate spacing, electrolysis time,solution concentration on the recovery efficiency of nickel was studied by. Then we chose pH, plate spacing., electrolysis time,solution concentration these four factors to do a the four factors three levels orthogonal experiment. The results showed that the effects of these four factors on the content of Ni2+, TP and Fe ions in the solution were from large to small, all of which were pH value> current intensity (A/m3)> electrolysis time (min)> plate spacing (cm). The best experimental condition is that the H value is 7, the electrolysis time is 30min, the plate spacing is 3cm, the current intensity is 0.8 A/m3. After the experiment, the concentration of Ni2+ and Fe in the solution is lower than the detection limit, the removal rate of total phosphorus is 94.86%.