Abstract Benzohydroxamic acid (BHA) is a universal collector for the flotation of oxidized minerals because of its excellent selectivity. However, improving collecting efficiency of BHA still remains a challenge in mineral processing. We report herein the substituted aryl-hydroxamic acids acted as collectors for scheelite flotation to compare the collecting effect with BHA. The collecting performance of BHA, p-methyl-benzohydroxamic acid (MBHA) and p-bromine-benzohydroxamic acid (BBHA) was investigated by flotation tests. Next, the adsorption behaviors of MBHA and BBHA on scheelite surface was studied via zeta potential and X-ray photoelectron spectroscopy (XPS) measurements. In addition, the electronic effect of substituents in MBHA and BBHA molecules were studied by Density Functional Theory (DFT) calculation. On the basis of these studies, bonding groups of MBHA molecule are better electron donors than BHA and BBHA, which are responsible for the superior adsorption effect and collecting performance towards scheelite than BHA and BBHA.

中文翻译：

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增强的电子效应提高了白钨矿浮选苯异羟肟酸的捕收效率

摘要 苯异羟肟酸（BHA）因其优异的选择性而成为氧化矿物浮选的通用捕收剂。然而，提高 BHA 的收集效率仍然是矿物加工中的一个挑战。我们在此报告了取代的芳基异羟肟酸作为白钨矿浮选的捕收剂，以比较其与 BHA 的捕收效果。通过浮选试验研究了BHA、对甲基-苯异羟肟酸(MBHA)和对溴-苯异羟肟酸(BBHA)的捕集性能。接下来，通过zeta电位和X射线光电子能谱（XPS）测量研究了MBHA和BBHA在白钨矿表面的吸附行为。此外，通过密度泛函理论 (DFT) 计算研究了 MBHA 和 BBHA 分子中取代基的电子效应。在这些研究的基础上，