Iron-containing oxides are the main minerals associated with roasted gold concentrates. The influence of different iron-containing oxides on the gold thiosulfate leaching process is very complex. In this study, we found the use of dry grinding methods can considerably eliminate the adverse effects on gold thiosulfate leaching under wet grinding conditions for a roasted gold concentrate containing hematite. The leaching results of gold ore showed that the gold leaching percentage was significantly improved from only 35% in 8 h under wet grinding conditions to 85% under dry grinding conditions. Using dry grinding to replace wet grinding, the loss of copper ions in the solution is much lower, and the diffusion coefficient of copper ions in the slurry is higher. Scanning electron microscopy (SEM) characterization shows that the passivation of the gold surface is much reduced. X-ray photoelectron spectroscopy (XPS) detection shows that the material adsorbed on the gold surface is mainly FeOOH. In addition, X-Ray diffraction (XRD) analysis results indicate that under wet grinding conditions, part of the hematite is transformed into goethite. Combined with the leaching results of gold powder, it is confirmed that the formed goethite during wet grinding is the cause of the deterioration of the gold leaching. Dry grinding can effectively avoid the formation of goethite and thus is a useful method to increase the gold leaching rate.

含铁氧化物是与烤金精矿有关的主要矿物质。不同的含铁氧化物对硫代硫酸金金浸出过程的影响非常复杂。在这项研究中，我们发现干磨法的使用可以大大消除湿磨条件下含赤铁矿的金精矿对硫代硫酸金浸出的不利影响。金矿的浸出结果表明，金的浸出率从湿磨条件下8 h的仅35％显着提高到干磨条件下的85％。用干磨代替湿磨，溶液中铜离子的损失要低得多，浆液中铜离子的扩散系数也要高。扫描电子显微镜（SEM）表征表明，金表面的钝化大大降低。X射线光电子能谱（XPS）检测表明，吸附在金表面的物质主要为FeOOH。此外，X射线衍射（XRD）分析结果表明，在湿磨条件下，部分赤铁矿转变为针铁矿。结合金粉的浸出结果，证实了在湿磨过程中形成的针铁矿是金浸出恶化的原因。干磨可有效避免针铁矿的形成，因此是提高金浸出率的有用方法。X射线衍射（XRD）分析结果表明，在湿磨条件下，部分赤铁矿转变为针铁矿。结合金粉的浸出结果，证实了在湿磨过程中形成的针铁矿是金浸出恶化的原因。干磨可有效避免针铁矿的形成，因此是提高金浸出率的有用方法。X射线衍射（XRD）分析结果表明，在湿磨条件下，部分赤铁矿转变为针铁矿。结合金粉的浸出结果，证实了在湿磨过程中形成的针铁矿是金浸出恶化的原因。干磨可有效避免针铁矿的形成，因此是提高金浸出率的有用方法。