Mechanism Of Selective Depression Of Galena By Sodium Alginate In Copper-lead Separation

Chalcopyrite and galena are often closely associated in polymetallic sulfide ores,both of which belong to typical sulfide ores.At present,potassium dichromate,metal sulfide and other agents are often used in flotation as depressants for the separation of the two.However,these agents have the disadvantages of high cost,toxicity and serious environmental pollution,so the development of efficient,non-toxic and environment-friendly flotation separation depressants for chalcopyrite and galena has always been a research hotspot of flotation agents.Sodium alginate is a non-toxic and environmentally friendly organic food additive with amphiphilic molecular structure and good adsorption of metal ions.It can be used as an depressant in the flotation separation of chalcopyrite and galena.For the purpose of taking chalcopyrite mineral,galena,for gangue mineral,the introduction of sodium alginate as flotation reagents,combined with experimental study and theoretical analysis,system research the chalcopyrite and galena flotation separation system,the selective depression behavior of galena,sodium alginate and the system was investigated on the basis of the mechanism of selective depression behavior of sodium alginate.The main research contents and innovative results are as follows:Sodium alginate has selective inhibition effect on galena in chalcopyrite-galena flotation system with ammonium butanate as collector.Solution chemical calculation shows that chalcopyrite and galena have very similar floatability in the flotation system with ammonium butanate as collector.The results of single mineral flotation confirmed that only ammonium butanum black powder was used as collector,and when the amount of ammonium butanum black powder exceeded 1×10~-44 mol/L,the flotation recovery rates of both were close to 100%,making it difficult to realize flotation separation.By adding sodium alginate as flotation inhibitor of flotation tests show that in the flotation system,sodium alginate can significantly reduce the flotability of galena,and had little influence upon the flotability of chalcopyrite,the dosage of sodium alginate for 30 mg/L,galena flotation recovery rate from 70.88%to 8.70%,chalcopyrite flotation recovery rate from 90.10%to 87.40%,to achieve efficient separation of the two.Ions in the flotation system have a certain effect on the selective inhibition of galena by sodium alginate.Flotation results showed that zinc ions and calcium ions had no effect on the selective inhibition of galena by sodium alginate,while copper ions and lead ions had negative effect on the selective inhibition of galena by sodium alginate.When the concentration of copper ions and lead ions is high(in the presence of sodium alginate),the floatability of galena increases to a certain extent,and the selective inhibition effect of sodium alginate decreases.Sodium alginate adsorbed stably on the surface of galena but not chalcopyrite.Zeta potential and infrared spectrum,X-ray photoelectron spectroscopy test and analysis results show that in the separation of chalcopyrite and galena flotation weak alkaline pH range,sodium alginate can significantly,selectively reduce the surface potential of galena,form a stable chemical adsorption in the surface of galena,covering the galena surface formed in networking adsorption layer structure,increase the hydrophilicity of galena,decrease the flotability of galena;Sodium alginate can complexate with copper ions under alkaline conditions,but the product is unstable and easy to decompose,so it cannot form adsorption on the surface of chalcopyrite and has no effect on the surface properties of chalcopyrite.