The selective separation of molybdenite from chalcopyrite is difficult because of their similar floatability in the presence of a collector. In this study, rhodanine-3-acetic acid (3-Rd) was first applied in molybdenite flotation as a novel chalcopyrite depressant, and its depression effect and mechanism were systematically investigated by flotation tests, density functional theory (DFT) calculation, zeta potential measurements, and X-ray photoelectron spectroscopy (XPS) analysis. Single mineral flotation results indicated that 3-Rd can selectively depress chalcopyrite flotation, whereas its effect on molybdenite is negligible. Mixed mineral and bench flotation tests further proved that 3-Rd is an efficient chalcopyrite depressant. The first-principle periodic calculations based on DFT predicted that 3-Rd prefers to adsorb onto Fe rather than Cu because of the more negative adsorption energy of the COO or CSS group on Fe in the chalcopyrite surface. Zeta potential measurements demonstrated that 3-Rd is adsorbed on chalcopyrite surface more selectively, and its adsorption strength is higher than that on molybdenite surface. XPS analysis further confirmed that 3-Rd is chemisorbed on chalcopyrite surface by binding with Fe active site and is adsorbed on molybdenite surface through hydrogen bonding and electrostatic interactions.

难于将辉钼矿与黄铜矿选择性分离，因为它们在捕收剂的存在下具有相似的漂浮性。在这项研究中，首先将Rhodanine-3-acetic acid（3-Rd）作为一种新型黄铜矿抑制剂用于辉钼矿浮选，并通过浮选试验，密度泛函理论（DFT）计算和zeta电位系统研究了其降压效果和机理。测量和X射线光电子能谱（XPS）分析。单一矿物浮选结果表明，3-Rd可以选择性地抑制黄铜矿浮选，而其对辉钼矿的影响可以忽略不计。矿物和台阶浮选混合试验进一步证明了3-Rd是一种有效的黄铜矿抑制剂。黄铜矿表面Fe上的COO或CSS基团。Zeta电势测量结果表明，3-Rd对黄铜矿表面的吸附选择性更高，其吸附强度高于辉钼矿表面。XPS分析进一步证实3-Rd通过与Fe活性位结合而化学吸附在黄铜矿表面，并通过氢键和静电相互作用吸附在辉钼矿表面。