Mechanism of sodium sulfide on flotation of cyanide-depressed pyrite

硫化钠对氰化抑制黄铁矿浮选的作用机理（英文）

The mechanism of sodium sulfide(Na2S)on the flotation of cyanide-depressed pyrite using potassium amyl xanthate(PAX)as collector was investigated by flotation test and electrochemical measurements.The flotation results show that both PAX and Na2S can promote the flotation recovery of cyanide-depressed pyrite and their combination can further improve the pyrite flotation recovery.Electrochemical measurements show that PAX and Na2S interacted with cyanide-depressed pyrite through different mechanisms.PAX competed with cyanide and was adsorbed on the pyrite surface in the form of dixanthogen,thus enhancing the hydrophobicity and flotation of cyanide-depressed pyrite.Unlike PAX,Na2S rendered the pyrite surface hydrophobic through the reduction of ferricyanide species and the formation of elemental sulfur S0 and polysulfide Sn2-.The combined application of PAX and Na2S induced superior pyrite flotation recovery because of a synergistic effect between PAX and Na2S.

通过浮选试验及电化学测试,研究戊基黄原酸钾(PAX)为捕收剂时硫化钠对氰化抑制黄铁矿浮选的作用机理。浮选结果表明,PAX和硫化钠单独使用时都可以提高氰化抑制黄铁矿的浮选回收率,但二者组合使用时对回收率的提升效果更加显著。电化学结果表明,PAX与硫化钠在氰化抑制黄铁矿的表面具有不同的作用形式,PAX可取代黄铁矿表面的氰根并以双黄药形式吸附于黄铁矿表面,导致黄铁矿表面疏水及可浮;而硫化钠可还原黄铁矿表面的铁氰化物并在黄铁矿表面生成单质硫和多硫化物,进而使黄铁矿表面疏水。组合使用时由于二者的协同作用会进一步提高黄铁矿的浮选回收率。