The effect of sulfide concentrate mineralogy and texture on Reactive Oxygen Species (ROS) generation
The effect of sulfide concentrate mineralogy and texture on Reactive Oxygen Species (ROS) generation
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DOI：
10.1016/j.apgeochem.2012.11.015
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发表时间：
2013-02-01
影响因子：
3.4
通讯作者：
Harrison, Susan T. L.
中科院分区：
文献类型：
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作者：
Jones, Gavin C.;Becker, Megan;Harrison, Susan T. L.
在酸性溶液中，硫化物矿物颗粒产生活性氧（ROS）H_2O_2和（OH）-O中心点。这种现象的影响，作为一个潜在的微生物应力引起的影响，已经研究了高温生物浸出性能的存在下，细磨黄铁矿和黄铜矿精矿。在这项研究中，硫化物矿物学对ROS生成的影响，在没有微生物的物理化学条件下典型的生物浸出环境进行了研究。获得了11个含硫化物矿物的不同样品的矿物学和元素组成。测试这些含Au、Cu和其它贱金属的硫化物矿物浓缩物以及低Cu品位的研磨的全矿石的ROS产生。当在恒定表面积负载基础上进行比较时，与含贱金属的精矿相比，含有约50%黄铁矿的整个矿石样品和两种难熔Au精矿产生显著更少的ROS。硫化物矿物相关的变量与ROS的产生。分别观察到FeS 2和CuFeS 2等级之间的显著差异，而样品中存在的两种矿物质的综合测量显示出与ROS生成的一致强相关性。含铜样品的铜品位、含铜硫化物总量和黄铜矿含量与活性氧的产生有很好的相关性。然而，一个共同的确定性变量与增加ROS的产生没有发现。一个子集的样品进行QEM-SCAN（R）的纹理分析。结果表明，减少硫化物矿物的释放，所造成的脉石硅酸盐矿物闭塞的解决方案，导致反应性降低，如在含Au的样品之一。良好的解放黄铜矿和黄铁矿相对应的样品的反应性增加。黄铁矿，这是目前在所有的反应样品，被证明是与其他硫化物矿物，暗示其重要性，在原电池的相互作用。微观分析黄铜矿和黄铁矿相从高活性样品显示了丰富的颗粒与广泛的开裂和可能存在的二次转化相（szomolnokite）。这些结果表明，硫化物矿物学，解放和物理处理的程度影响硫化物精矿在酸性溶液中的反应性。(c)2012爱思唯尔有限公司保留所有权利。
The generation of Reactive Oxygen Species (ROS), H2O2 and (OH)-O-center dot, has been observed from sulfide mineral containing particles in acidic solutions. The implications of this phenomenon, as a potential microbial stress-causing effect, have been studied previously with respect to thermophilic bioleaching performance in the presence of finely milled pyrite and chalcopyrite concentrates. In this study, the effect of sulfide mineralogy on ROS generation in the absence of microbes under physicochemical conditions typical for the bioleach environment was investigated. The mineralogical and elemental composition of eleven different samples containing sulfide mineral was obtained. These Au, Cu and other base metal-containing sulfide mineral concentrates as well as a milled whole ore of low Cu grade were tested for ROS generation. The whole ore sample and two refractory Au concentrates containing approximately 50% pyrite, generated significantly less ROS compared to the base metal-containing concentrates when compared on a constant surface area loading basis. Sulfide mineral-related variables were correlated with ROS generation. A significant difference was observed between FeS2 and CuFeS2 grades separately, whereas a combined measure of both minerals present in samples showed a consistently strong correlation to ROS generation. The Cu grade, total Cu-containing sulfides and the chalcopyrite content of Cu-containing samples correlated well with ROS generation. However, a common deterministic variable with a strong association to increased ROS generation was not found. A sub-set of samples were subjected to QEM-SCAN (R) for textural analysis. Results suggested that a decrease in sulfide mineral liberation, caused by gangue silicate mineral occlusion to solution, resulted in decreased reactivity as shown in one of the Au-containing samples. Well-liberated chalcopyrite and pyrite phases corresponded to increased reactivity of samples. Pyrite, which was present in all of the reactive samples, was shown to be associated with other sulfide minerals, implicating its importance in galvanic interactions. Micro-analysis of chalcopyrite and pyrite phases from highly reactive samples showed an abundance of particles with extensive cracking and the possible presence of secondary transformation phases (szomolnokite). These results suggest that sulfide mineralogy, liberation and extent of physical processing affect sulfide mineral concentrate reactivity in acidic solutions. (c) 2012 Elsevier Ltd. All rights reserved.