Study On The Fundamental And Application Of Flotation Separation Of Copper-lead Sulphide Concentrate With Sulfurous Acid

Abstract:Smelting non-ferrous metal sulfide ores will produce large amounts of sulfur dioxide gas. If this gas can be effectively applicated in mineral processing, it will not only reduce the flotation reagent cost, but also reduce sulfur dioxide emissions pollution to the environment. This study employed sulfurous acid as depressant, butyl xanthate as collector for the flotation test, used infrared spectra analysis, contact angle measurement and electrochemical measurement, etc. for fundamental research. The main conclusions are as follows:(1) The single mineral flotation test showed that when the dosage of butyl xanthate was low, the floatability of chalcopyrite was better than galena. Sulfurous acid could depress galena and promote the flotation of chalcopyrite, sodium sulfite had depression effect on galena while none on chalcopyrite, the former was more selective than the latter. Moderately raising the pulp temperature was conductive to sulfurous acid’s depression. Raising the pH after sulfurous acid reacting could both depress chalcopyrite and galena, the best pH value for separating was5. The flotation separation test of manually mixed showed that sulfurous acid has good selective depression to chalcopyrite and galena.(2) The infrared spectra experiment showed that sulfurous acid could benefit butyl xanthate adsorbing on chalcopyrite, while hinder adsorbing on galena. Lead sulfite was produced after galena reacting with sulfurous acid.(3) Contact angle measurement showed that sulfurous acid and sodium sulfite had no obvious effect on contact angle of chalcopyrite surface, but could reduce the contact angle of galena surface, sulfurous acid was more effective than sodium sulfite. Moderately raising the temperature was beneficial to sulfurous acid’s effect.(4) The result of cyclic voltammetry experiment showed that regulated by electrochemical, in butyl xanthate solution, xanthate copper and sulphur were produced on chalcopyrite surface.xanthate lead on galena surface, then be oxidized to dixanthogen. Lead sulfate was produced on galena surface when in sulfurous acid solution.(5) The result of Tafel experiment showed that butyl xanthate could hinder the corrosion of chalcopyrite and galena, while sulfurous acid promoted chalcopyrite’s corrosion but hinder galena’s corrosion.(6) A good flotation index was obtained when using sulfurous acid to separate a copper-lead sulphide concentrate.