Preparation And Properties Of The A1-based Pb-pan Composite Coating Electrodeposited Study

Zinc is abundant in China, and the process of electrodeposited Zn is an important process in hydrometallurgy of zinc. At present, Pb-Ag alloy anode materials are widely used in the hydrometallurgy of zinc in the industrial production. However, there are many disadvantages, such as low current efficiency, high cell voltage and the low quality of zinc and so on. So in this paper the preparation of the new type of Pb-PAN composite anode materials is in order to solve the problem of anode materials used in Zinc electrodeposition. In this paper, the experiments choose aluminum as the matrix, adding the PAN into fluoride system as the composite plating solution and using electro-deposition method to prepare the new type of Pb-PAN composite anode material.The subject is from the scientific and technological innovation projects of Yunnan province:The research and industrial technology of the preparation of the new type energy-saving anode materials used in non-ferrous metallurgical industry.This study is mainly divided into three parts as follows:1.The preparation of polyaniline composite coatings and the research of electrochemical properties.(1)The determination of process parameters. At first, the effect of conditions of plating process on the electrochemical properties of the Pb-PAN composite coatings are studied by means of the condition experiments (such as polyaniline concentration, current density, bath temperature,etc.) and the most appropriate parameters and conditions of the experiment are got.(2)The results of the electrochemical tests shows that the electro-catalytic properties of Pb-PAN composite coating is superior to the pure lead and lead-silver alloy coatings.Corrosion resistance test shows that the corrosion resistance of composite coating is improved than pure lead coating, it is better in the acidic environment than in the neutral environment.2.The analysis of the surface appearance,structure and phase analysis of Pb-PAN composite coating.(1)Infrared spectral analysis shows that, Pb-PAN composite coating has characteristic peak of polyaniline, it is clear that heavy metals do not undermine the structure of polyaniline, but shifted some peaks, it is indicated that some reactions may be occurred between groups of polyaniline and heavy metal lead.(2)The phase analysis of Pb-PAN composite coating by X-ray diffraction shows that the composite coating almost is lead-based and is not detected PAN diffraction peak.Probably, because of the low content of PAN, diffraction peak of PAN is overcastted by the diffraction peak of Pb. Probably, because PAN is amorphous.(3)The analysis results of Scanning electron microscopy showed that:the flocculent material is PAN.Some PAN is wraped in lead crystal and some PAN was embed between lead crystals. The station of some PAN are accumulation. Spectroscopy detection confirms that there is the carbon element at any point of the spectrum, but the content is different. The PAN is not well-proportioned.3. The application of Pb-PAN composite coating in electrodeposition zinc. The indexs of composite coating such as current efficiency, cell voltage and so on, is superior to pure lead coating, but the operational life span need to be improved.