| As the economy developing, the problem of metal corrosion is more and more serious. Plating and chemical plating are classic and effective method of preventing corrosion. But even the most advanced technology couldn't make sure zero unqualified plating articles during producting, and these unqualified plating articles would effected the enterprise's economical benefit if been discarded directly, and it also would cause the wasting of resource. At precent, the nickle stripping technics was used diffusely in the technics of replating unqualified plating articles. But most of traditional nickel stripping technics were cyanidation and nitric acid method, these traditional technics were not only poison on stream, the treatment of its waste liquid was also difficult and it's so hard to match the standard of discharge. So, it was absolutely necessary to study on the inventment of environment nickel stripper.The purpose of this task was to excogitate a new recycle and regenerational nickel stripper and its technics. In this paper, the ethylenediamine and NBS were used as the main ingredients of this new nickel stripper, and ingredients radio of this nickel stripper, condition of operation, stripping technics and recycle-regeneration were studied across-the-board by static-eching-hanging method, electrodeposition and the method of replenishment.Besides that, the comparation and analysis between the new technics and traditional technics was made from the angle of product security and environment protection.By lots of experiment:the ingredient of recycle-regeneration nickel stripper, espe-cial the concentration of ethylenediamine and NBS, dosage of phosphoric acid, category and dosage of additive, condition of operation that including pH, temperature would effected the index of nickel-coating stripping(speed of nickel stripping, speed of iron corrosion, performance of substrate material, capacity of nickel stripping) so much. The optimum condition is:concentration of ethylenediamine, NBS, phosphoric acid, sodium dodecyl sulfate are 80ml/L, 60g/L, 90ml/L and 0.1 g/L respectively, the pH is 10.5 and the temperature is 80℃; Under this condition, the speed of nickel coating stripping is the fastest and without any corrosion to the substrate iron material. The optimum compositions of Hydrogen peroxide as the oxidant and Sodium pyrophosphate as corrosion inhibitors, and operating parameters have been obtained. The optimized factors are as follows:Hydrogen peroxide 0.5%; Sodium pyrophosphate 0.5g/L; operating temperature 50～60℃and agitation meanwhile; And under this condition, the film at the surface of substrate material can be removed quickly and the good coating is regained. Studying the volume of nickel stripping and condition of recycle-regeneration by electrodeposition and ingredients replenish method, and the conclusion is as following:when the speed of nickel stripping can't match the requirement of product, by replenish 20% of the 60g/L NBS,20% of the 80ml/L ethylenediamine,0.5g/L DDTC can promote the speed of nickel stripping which meet the requirement of product, moreover, by this way of replenish, this nickel stripper can be regenerated for 5 times and the total nickel stripping volume can be 53g/L.The data are shown:this recycle-regeneration nickel stripper is not just match the requirement of replating in current industry, but also fulfilled the replacement of toxic chemical material, and it abated the environmental harmfulness, the future of this new technics can't be belittled.
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