无捕收剂浮选时硫化矿物表面的疏水—亲水平衡关系

通过硫化矿物表面中性硫(S~o)的溶剂提取-化学分析、矿浆电位测定和浮选试验,建立了自诱导浮选和硫化钠诱导浮选的疏水-亲水平衡关系,分别用S~o]/OH~-]和S~o]/OH~-]+HS~-])表示S~o的生成量S~o]受矿浆电位调控研究结果表明,pH值相同时,S~o]值越大,矿物表面疏水性高,浮选行为好pH值高,OH~-]值高,矿物表面亲水性大,浮选需要的S~o]多;反之亦然同一pH值下,硫化钠诱导浮选所需S~o]较自诱导浮选高

HYDROPHOBICITY-HYDROPHILICITY BALANCE RELATIONSHIPS FOR COLLECTORLESS FLOTATION OF SULPHIDE MINERALS

Hydrophobicity-hydrophilicity balance relationships for collectorless flotation, including self-induced and Na_2S-induced flotation, have been established, through solvent extraction-chemical analyses of neutral sulphur (S~0) from sulphide mineral surfaces, measurements of pulp potential and flotation tests. They may be indicated as S~0]/OH~-] andS~0]/(OH~-]+HS~-]) respectively. The neutral sulphur extracted was considered to be re- sponsible for the hydrophobicity, and the amount of which was controlled by pulp potential. The critical value of neutral sulphur amount was proposed as a new concept, and was used to indicate the hydrophobic degree and flotation behaviour. The hydrophilicity was attributed to OH~- ion for self-induced flotation and both OH~- and HS~- ions for Na_2S-induced flotation. At a given pH value, hydrophobicity and floatability increase with the amount of neutral sulphur extracted. At different pH values, the higher pH results in the stronger hydrophilicity, and hence hydrophobicity and flotation require more amount of S~0. The lower pH values are in correspondence with smaller amount of S~0. The critical value of amount of S~0 to Na_2S-induced flotation is higher than that to self induced flotation because of the hydrophilicity of HS~- ions.