Experimental Study On Leaching Separation Of Manganese And Zinc From Smelter Smelting

Manganese resources are increasingly scarce restricting the production and sustainable development of China’s manganese product. Economic and rational use of low-grade manganese ore, ferromanganese smelting smoke ash, manganese waste and other resources, has important strategic significance on alleviating the shortage of manganese resources, promoting the development of the western economy, and ensuring the sustainable development of manganese products industry.At present, domestic and foreign research on rhodochrosite and high-grade manganese ore is more than research on complex low-grade manganese ore and ferromanganese smelting smoke. Researchs which give method on taking efficient and economical advantage of low-grade manganese ore and ferromanganese smelting smoke ash are even less. This study is based intractable ferromanganese smelting smoke ash as raw material, ferrous sulfate as a reducing agent, using sulfuric acid pressure leaching to obtain manganese sulfate leach solution. Thereby further purify to remove zinc and other impurity ions of the solution, to obtain a solution for the production of manganese. Study of the process of ferromanganese smelting smoke ash utilization provides an effective way to achieve the comprehensive utilization of secondary resources, to achieve the purpose of energy saving.Firstly, after the water leaching of ferromanganese smelting smoke gray, raw potassium content of17.26%is down to5.93%, manganese content is increased from20.37%to30.23%, and the content of zinc is rose from8.95%to12.68%. This enables the leaching of potassium, while enriching elements of manganese and zinc. The particle size analysis of smoke ash treated after water leaching shows that particle size distribution of the sample material is between0.035～69.183μm, the volume average particle size is8.678μm. As can be seen from the SEM image, the feedstock is irregular, amorphous particles.With FeSO47H2O as a reducing agent, manganese and zinc in ferromanganese smelting dust ash are leached in the form of Mn2+, Zn2+by sulfuric acid. After the leaching reaction, adjust pH to4-5to remove iron. The highest leaching rate of manganese reaches96.76%and that of zinc is84.88%. The optimal leaching condition is as follows:reaction temperature is90℃, concentration of H2SO4is20%, reaction time is4hours, liquid-solid ratio is5:1, dosage of FeSO4·7H2O is75g, and stirring rate is300r/min.Under the optimum conditions, zinc is separated from the manganese leachate of which manganese content is40.5965g/L and zinc content is7.3523g/L. In the resulting separated liquid, manganese content is41.2444g/L, the zinc content is1.9283g/L. In the separation process,7.55%of manganese is lost, and zinc removal rate is76.13%. Studies have shown that the optimal process conditions are as follow: pH is adjusted to7.00with concentrated aqueous ammonia solution, the reaction temperature is60℃, reaction time is2h, stirring speed is300r/min, standing time is Oh.The manganese content is45.2208g/L, the zinc content of4.1321g/L of manganese to the separation liquid purification optimum experimental conditions for curing, resulting in purification of manganese content was44.5159g/L, the zinc content of0.2511g/L. In the purification process, the loss rate of manganese content is1.62%, and93.98%of zinc content is removal. As is showed in the study, the optimum conditions of the vulcanization purification reaction are as follow:pH of the solution is2.00, Na2S·9H2O is added an amount of7.5g, reaction time is1h, reaction temperature is room temperature, stirring rate is300r/min.