Conventional inorganic depressants are widely used to separate pyrite in the flotation process of chalcopyrite, however, their widespread use entails some inevitable disadvantages, such as low-selectivity, additional costs, and especially hypertoxicity. In this work, we tested locust bean gum (LBG), a natural polysaccharide polymer, as a selective depressant in the Cu-Fe flotation separation. Micro-flotation tests suggested that at a slurry pH of 8.0, the addition of LBG dramatically depressed the floatability of pyrite while having a negligible depressive effect on chalcopyrite. The results of surface adsorption experiments, contact angle and zeta potential measurements showed that the adsorption of LBG on the pyrite surfaces was stronger than that on the surfaces of chalcopyrite. Moreover, XPS and FT-IR analyses further suggested that LBG was adsorbed on the pyrite surfaces by physical adsorption. The acid/base interactions, hydrogen bonding, and the attraction between the hydrophobic sections of both LBG and pyrite surfaces, were considered as the potential mechanisms in the adsorption of LBG on pyrite.

传统的无机抑制剂在黄铜矿浮选过程中被广泛用于分离黄铁矿，但其广泛使用也带来了一些不可避免的缺点，如选择性低、成本增加，尤其是毒性较大。在这项工作中，我们测试了刺槐豆胶 (LBG)，一种天然多糖聚合物，作为 Cu-Fe 浮选分离中的选择性抑制剂。微浮选试验表明，在 8.0 的浆液 pH 值下，LBG 的加入显着降低了黄铁矿的可浮性，而对黄铜矿的抑制作用可忽略不计。表面吸附实验、接触角和zeta电位测量结果表明，LBG在黄铁矿表面的吸附强于黄铜矿表面。而且，XPS 和 FT-IR 分析进一步表明 LBG 通过物理吸附吸附在黄铁矿表面。酸碱相互作用、氢键以及 LBG 和黄铁矿表面疏水部分之间的吸引力被认为是 LBG 在黄铁矿上吸附的潜在机制。