As basic chemical materials, many products produced by our company are used widely in the aspects of electroplating and corrosion protection. Because of strong oxidizing property, potassium permanganate can be used widely for building waterproofing, metal surface treatment, plastic electroplating, ect in daily life.
1. Remove the iron impurities in the bath (zinc plating bath): use potassium permanganate ferrous oxide to generate flocculent ferric hydroxide easily to be removed by precipitation. The iron impurities in zinc plating bath are co-deposited in ferrum in zinc, with difficulty in passivation, and excessive potassium permanganate must be dosed in order to remove ferrum thoroughly, but remaining potassium permanganate wll also break the brightener added later. Therefore, after precipitation and filtration for removal of iron impurities, about 1mL 30% hydrogen peroxide should be added in the test to reduce the residual potassium permanganate. And after they act for a while, sample the liquor for test and adjust the brightener.
2. Quicken the surface passivation of aluminium alloy material by means of potassium permanganate. Potassium permanganate, instead of hexavalent chrome, can be used for metallochrome passivation in the passivation process of aluminium and its alloy and also be used as additive for chemical polishing of aluminium and its alloy. E.g., Sheng-Song Ge, et al have generated black chromium-free conversion firm in KMnO4 solution. KMnO4 concentration in its solution is 6g/L. After oxidation two times, the corrosion resistance of aluminum alloy has been enhanced. The film is mainly composed of Al2O3 and various oxides of manganese. Generally speaking, hypermanganate is not a good kind of corrosion inhibitor for aluminium and its alloy but can accelerate the corrosion.
3. Potassium permanganate can be used for chemical coarsening treatment of some materials in the plastic electroplating and also to metallize walls of circuit board manufacturing holes. The method that active groups are formed on plastic surface can be utilized to absorb metallic ions so that the surface has catalytic activity, a bit similar to manufacturing of printed board. For a kind of thermosetting allyl-dimethyl-phenylate alkene resin, after the surface is coarsened with potassium permanganate and sodium hydroxide, use sulfuric acid for sulfonation to exchange sulph as positive ion with base groups and introduce them on the surface so as to absorb the copper ions. Soak this plastic with surface catalytic activity in the bluestone solution, and reduce the immersion liquid by sodium borohydride to obtain the chemical plating copper layer. Optimum process condition of potassium permanganate coarsing: 20g/L potassium permanganate, coarsing temperature 70℃, coarsing time 40min. (Sun Dun, He Jianping, et al. Potassium Permanganate Pretreatment Process of ABS Plastic Electroplating [J]. Materials Protection, 2009, 42(12)