Pacific Centre for Isotopic and Geochemical Research, Department of Earth and Ocean Sciences, University of British Columbia (UBC), Vancouver, BC, Canada V6T 1Z4.
Sci Total Environ. 2010 May 1;408(11):2357-68. doi: 10.1016/j.scitotenv.2010.02.016. Epub 2010 Mar 6.
To evaluate metallurgical processing as a source of Zn and Cd isotopic fractionation and to potentially trace their distribution in the environment, high-precision MC-ICP-MS Zn, Cd and Pb isotope ratio measurements were made for samples from the integrated Zn-Pb smelting and refining complex in Trail, B.C., Canada. Significant fractionation of Zn and Cd isotopes during processing of ZnS and PbS ore concentrates is demonstrated by the total variation in delta(66/64)Zn and delta(114/110)Cd values of 0.42 per thousand and 1.04 per thousand, respectively, among all smelter samples. No significant difference is observed between the isotopic compositions of the Zn ore concentrates (delta(66/64)Zn=0.09 to 0.17 per thousand; delta(114/110)Cd=-0.13 to 0.18 per thousand) and the roasting product, calcine (delta(66/64)Zn=0.17 per thousand; delta(114/110)Cd=0.05 per thousand), due to approximately 100% recovery from roasting. The overall Zn recovery from metallurgical processing is approximately 98%, thus the refined Zn metal (delta(66/64)Zn=0.22 per thousand) is not significantly fractionated relative to the starting materials despite significantly fractionated fume (delta(66/64)Zn=0.43 per thousand) and effluent (delta(66/64)Zn=0.41 to 0.51 per thousand). Calculated Cd recovery from metallurgical processing is 72-92%, with the majority of the unrecovered Cd lost during Pb operations (delta(114/110)Cd=-0.38 per thousand). The refined Cd metal is heavy (delta(114/110)Cd=0.39 to 0.52 per thousand) relative to the starting materials. In addition, significant fractionation of Cd isotopes is evidenced by the relatively light and heavy isotopic compositions of the fume (delta(114/110)Cd=-0.52 per thousand) and effluent (delta(114/110)Cd=0.31 to 0.46 per thousand). In contrast to Zn and Cd, Pb isotopes are homogenized by mixing during processing. The total variation observed in the Pb isotopic compositions of smelter samples is attributed to mixing of ore sources with different radiogenic signatures.
为了评估冶金加工过程是否为锌和镉同位素分馏的来源，并有可能追踪它们在环境中的分布，我们对加拿大不列颠哥伦比亚省 Trail 的综合锌-铅冶炼和精炼厂的样品进行了高精度 MC-ICP-MS 锌、镉和铅同位素比值测量。对 ZnS 和 PbS 矿石精矿进行加工时，Zn 和 Cd 同位素发生了显著的分馏，所有冶炼厂样品的 δ66/64Zn 和 δ114/110Cd 值总变化分别为 0.42‰和 1.04‰。锌矿石精矿（δ66/64Zn=0.09 至 0.17‰；δ114/110Cd=-0.13 至 0.18‰）和焙烧产物（煅烧）之间的同位素组成没有明显差异，这是由于焙烧的回收率约为 100%。由于冶金加工过程的总 Zn 回收率约为 98%，因此相对于起始材料，精炼的 Zn 金属（δ66/64Zn=0.22‰）并没有明显分馏，尽管烟尘（δ66/64Zn=0.43‰）和废水（δ66/64Zn=0.41 至 0.51‰）中存在明显的分馏。冶金加工过程中 Cd 的计算回收率为 72-92%，大部分未回收的 Cd 在 Pb 操作过程中损失（δ114/110Cd=-0.38‰）。精炼的 Cd 金属相对于起始材料较重（δ114/110Cd=0.39 至 0.52‰）。此外，烟尘（δ114/110Cd=-0.52‰）和废水（δ114/110Cd=0.31 至 0.46‰）中轻、重同位素组成的差异表明，Cd 同位素发生了显著分馏。与 Zn 和 Cd 不同，Pb 同位素在加工过程中通过混合而均匀化。冶炼厂样品中观察到的 Pb 同位素组成的总变化归因于具有不同放射性特征的矿石来源的混合。
