Investigation On Preparation Of Tribasic Lead Sulphate And Lead Oxide Phosphite Hydrate From Bismuth Hydrometallurgy Waste Residue

The processing principle on preparation tribasic lead sulphate from bismuth hydrometallurgy waste residue through ammonium hydrogen carbonate transformation—nitric acid leaching—lead deposition with sulphuric—sodium hydroxide synthesis and on preparation lead oxide phosphite hydrate through ammonium hydrogen carbonate transformation—nitric acid leaching—lead deposition with sulphuric—sodium hydroxide retransformation—phosphite acid synthesis are introduced in the study.The influence factors on reclaiming rate of lead in the processing of ammonium hydrogen carbonate transformation have been studied in detail, including the amount of ammonium hydrogen carbonate , acetic acid , reaction time , liquid-to-solid and so on. The optimum preparing conditions have been obtained through the orthogonal experiment, which are: NH₄HCO₃ / Pb(molar ratio) of 2. 5: 1, reaction time of 2. 5h at room temperature, acetic acid of 0%, liquid-to-solid ratio of 2 and the radium of particulate is not larger than 0. 097mm.The concentration of nitric acid was found to have great effect on reclaiming rate of lead in the processing of nitric acid leaching—lead deposition with sulphuric The optimum processing parameters have been obtained through the orthogonal experiment, which are: the concentration of nitric acid of 15%, lead deposition temperature of 40 ℃, H₂SO₄/Pb(molar ratio) of 1. 2.- 1, lead deposition time of 2.0 h, nitric acid leaching time of 1. 5h, concentration of sulphuric of 40% and HNO₃/Pb(molar ratio) of 3: 1, the reclaiming rate of lead is obtained 99.25% and the rate of waste residue is 3% under optimum processing parameters.The influence factors on oxide lead content in the processing of sodium hydroxide synthesis have been studied in detail, including the ratio of sodium hydroxide, reaction time, reaction temperature and so on. The optimum processing parameters have been obtained through the orthogonal experiment, which are: the ratio of sodium hydroxide of 1. 2, reaction time of 3 hours and reaction temperature...