Global Centre for Environmental Remediation (GCER), Faculty of Science, The University of Newcastle, Callaghan, NSW, 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC-CARE), The University of Newcastle, University Drive, Callaghan, NSW, 2308, Australia; Department of Soil Science, Sher-e-Bangla Agricultural University, Dhaka, 1207, Bangladesh.
Global Centre for Environmental Remediation (GCER), Faculty of Science, The University of Newcastle, Callaghan, NSW, 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC-CARE), The University of Newcastle, University Drive, Callaghan, NSW, 2308, Australia.
J Hazard Mater. 2020 Nov 15;399:123029. doi: 10.1016/j.jhazmat.2020.123029. Epub 2020 May 30.
Trace element contamination from abandoned mine sites is a major threat to the environment. The distribution of trace elements in various particle size fractions of soils from abandoned mine sites plays a critical role in designing remediation approaches. This study investigated the geochemical distribution of trace element enrichment and mineralogical composition in various particle size fractions from contrasting abandoned mine sites (Webbs Consols, Halls Peak and Mole River, Australia). Results revealed that arsenic and other element concentrations increased with decreasing particle size for samples from Webbs Consols and Halls Peak. The highest arsenic (3.05%), lead (3.23%) and zinc (1110 mg/kg) were found in the finest fraction (<0.053 mm). In Mole River, the highest concentration of arsenic (10.8%), lead (209 mg/kg) and zinc (351 mg/kg) were observed in coarse fractions. Arsenic fractionation by sequential extraction showed that arsenic was strongly associated with the amorphous and crystalline iron phases. X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies revealed that tooeleite (a ferric arsenite mineral, also confirmed by Transmission electron microscopy (TEM)), arsenopyrite, scorodite and arsenolite were the dominant arsenic minerals. The study showed elevated levels of arsenic bearing minerals across particle sizes which has significant implications for remediation approaches at abandoned mine sites.
废弃矿山的微量元素污染是对环境的主要威胁。废弃矿山土壤中不同粒径颗粒中微量元素的分布对修复方法的设计起着至关重要的作用。本研究调查了来自澳大利亚 Webb's Consols、Halls Peak 和 Mole River 等不同废弃矿山的不同粒径颗粒中微量元素富集和矿物成分的地球化学分布。结果表明，砷和其他元素的浓度随 Webbs Consols 和 Halls Peak 样品粒径的减小而增加。在最细的颗粒(<0.053mm)中发现了最高的砷(3.05%)、铅(3.23%)和锌(1110mg/kg)。在 Mole River，粗颗粒中砷(10.8%)、铅(209mg/kg)和锌(351mg/kg)的浓度最高。顺序提取的砷分馏表明，砷与无定形和结晶铁相强烈相关。X 射线衍射(XRD)和扫描电子显微镜(SEM)研究表明，针铁矿(一种铁砷酸盐矿物，也通过透射电子显微镜(TEM)证实)、毒砂、砷镍矿和砷华是主要的砷矿物。研究表明，在各个粒径范围内都存在含砷矿物的含量升高，这对废弃矿山的修复方法具有重要意义。
