A proof-of-concept for the carbonation-assisted processing of ultramafic nickel ores is presented. Carbonation converts serpentine, the primary gangue or undesirable mineral, to magnesite. It prevents slime coating of fine gangue minerals on pentlandite, the main nickel-bearing mineral, during froth flotation, and improves nickel recovery and concentrate grade. Additionally, CO₂ is captured and stored in the form of solid carbonates, thus removing it from the atmosphere. Microflotation experiments demonstrated improved nickel recovery (61.2 to 87.4 wt%) and concentrate grade (20.6 to 24.7 wt%) in carbonated vs. uncarbonated systems. The mechanism behind the improved nickel flotation was investigated by zeta potential measurements, optical imaging microscopy, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. These analyses confirmed the absence of slime coating in the carbonated system under the flotation conditions tested. Finally, a preliminary techno-economic analysis was performed to evaluate the cost metrics of incorporating carbonation into nickel mineral processing.

中文翻译：

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用于镍加工中蛇纹石减排的矿物碳化：迈向工业碳捕获和储存的一步

介绍了超镁铁镍矿碳酸化辅助加工的概念验证。碳酸化作用将蛇纹石、主要脉石或不良矿物转化为菱镁矿。在泡沫浮选过程中，它可以防止细粒脉石矿物在主要含镍矿物 pentlandite 上发生粘液涂层，并提高镍回收率和精矿品位。此外，CO ₂以固体碳酸盐的形式被捕获和储存，从而将其从大气中去除。微浮选实验表明，在碳酸盐中，镍回收率（61.2 至 87.4 重量%）和精矿品位（20.6 至 24.7 重量%）在碳酸盐与非碳酸中均有提高。非碳酸化系统。通过 zeta 电位测量、光学成像显微镜、X 射线光电子能谱和飞行时间二次离子质谱法研究了改进的镍浮选背后的机制。这些分析证实，在所测试的浮选条件下，碳酸化系统中不存在煤泥涂层。最后，进行了初步的技术经济分析，以评估将碳化纳入镍矿物加工的成本指标。