| In the modern lead industry, the production of lead involves fire metallurgy to produce crude lead from lead concentrates and electrolysis of the crude lead to produce electrolytic lead, then deep processing to prepare lead materials. Owing to the emission of SO2 and lead vapour as well as lead filled dust during processes of lead metallurgy and electrolysis, so there is serious pollution to environment. Under the current pressures of strict environmental regulations, it is necessary to seek other methods to produce lead materials. In this paper, a new approach to direct produce lead monoxide from galena concentrates has been proposed.PbO powders as an active material of lead acid batteries are prepared from galena concentrates through three-step, including leaching, selective purification and chemical synthesized. This process without pollution not only simplifies the traditional process of the production of PbO, but enhances the efficiency of processing lead mineral resources.In this thesis, two sorts of leaching systems both ammonium carbonate system and ferric chloride system were investigated respectively. The results of leaching experiments in ammonium carbonate system indicate that leaching rate is not more than 60%. The reason for lower leaching rate is the formation of passivation film which is composed of PbCO3 crystal from X-ray diffraction analysis. Comparatively, in ferric chloride system leaching rate can reach 97.39% just for 40 minutes. It is further found that the process of cooling, crystallization and filtration has the function of purification. By means of solution chemistry calculation, it demonstrates that [PbCl4]2- is the dominant species for the reaction product of PbCl2, which begins to dissolve around pClop 0.04 ([Cl-]T=0.918mol/L). The results of corrosion electrochemistry present that corrosion current increases with the increase of ferric chloride concentration, but passivation phenomenon would be appeared while the ferric concentration is above of 6×10-4 mol/L. And corrosion current in sodium chloride solution is higher than without it, which shows that chloride ions greatly contribute to the improvement of leaching rate duoto complexation of chloride. /? -PbO prepared in this thesis is rhombic. There is no other product from X-ray diffraction analysis with the average particle size of /?-PbO of 4.102um, and it is flaky powder from scanning electron microscope spectrum. Intermediate samples, including PbOx, PbsO4 and p -PbO, can exist stably in the process of calcining the precursor at different temperature.On the other hand, the production of secondary lead resources is also important to all of lead industry, which is in the initial stage of development in China. In this thesis, three-step process for ultrafine powder of PbSO4, including carbonation transformation of lead pastes in sodium carbonate solution, chemical dissolving and method of chemical sedimentation, has been presented. Orthogonal designing was applied to study the correlation of factors connected with conversion rate. The results shows that their influencing order is: Na2CO3 concentration > reaction temperature > reaction time > stirring speed, and the optimum conversion condition is also obtained. The characters of calcining reaction for lead pastes transformed by carbonation were studied by TG-DTA. The results expressed that lead sulfate in lead pastes can be transferred into lead carbon, completely, which makes the calcining temperature of lead pastes decrease from 880.56°C to 357.86°C and avoid emission of SO2 during disposing waste lead storage batteries by fire metallurgy, as well as diminish energy use. With the lead pastes after transformation dissolved by fluosilicate acid, and then synthesized by the method of chemical sedimentation, orthorhombic lead sulfate would be prepared. There is no other product from X-ray diffraction analysis and its average particle size is about 3.224um.
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