柠檬酸在含碳酸盐赤铁矿浮选体系中的分散机理

以赤铁矿、菱铁矿和石英为研究对象,通过沉降试验、Zeta电位测试、傅里叶红外光谱分析和溶液化学计算研究了柠檬酸在强碱性条件下(pH=11.0)的分散机理.沉降试验结果表明,柠檬酸对人工混合矿(赤铁矿-菱铁矿-石英)具有较好的分散效果.动电位和红外光谱测试表明,柠檬酸在赤铁矿和菱铁矿表面的吸附较强烈并使其动电位负移,而在石英表面的吸附较弱并对石英动电位影响较小.溶液化学计算表明,柠檬酸主要以[C_6H_5O_7]~(3-)的形式吸附在赤铁矿和菱铁矿的羟基化表面,进而阻止矿粒间的凝聚.结果表明柠檬酸在含碳酸盐赤铁矿浮选体系中具有分散作用.

Dispersion Mechanism of Citric Acid in Flotation System of Hematite Containing Carbonate

Sedimentation tests， Zeta potential measurements， FTIR (Fourier transform infrared spectros copy) spectroscopy， and solution chemistry calculations were used to investigate the dispersion mechanism of citric acid in strong alkaline conditions (pH=11.0). The sedimentation testing results show that the mixed minerals (containing hematite， siderite， and quartz) can be partly dispersed by citric acid. The results of Zeta potential measurements and FTIR spectroscopy indicate that citric acid mainly absorbs on siderite and hematite surface and partly brings their Zeta potentials down， while the Zeta potential of quartz is slightly influenced and the adsorption of citric acid on quartz surface is weak. The solution chemistry calculations indicate that citric acid interacts with the hydroxylation surface of hematite and siderite by the form of ［C₆H₅O₇］^3- toprevent the coagulation of minerals， which might explain the dispersion mechanism of citric acid in flotation system of hematite containing carbonate.