Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, National Engineering Research Center of Urban Environmental Pollution Control, Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing 100037, China.
Beijing Institute of Mineral Resources and Geology, Beijing 101500, China.
Int J Environ Res Public Health. 2022 Feb 10;19(4):1979. doi: 10.3390/ijerph19041979.
Soils at primary explosives sites have been contaminated by high concentrations of antimony (Sb) and co-occurring heavy metals (Cu and Zn), and are largely overlooked and neglected. In this study, we investigated Sb concentrations and species and studied the effect of combined Fe- and Fe-Al-based sorbent application on the mobility of Sb and co-occurring metals. The content of Sb in soil samples varied from 26.7 to 4255.0 mg/kg. In batch experiments, FeSO showed ideal Sb sorption (up to 97% sorption with 10% FeSO·7HO), whereas the sorptions of 10% Fe and 10% goethite were 72% and 41%, respectively. However, Fe-based sorbents enhanced the mobility of co-occurring Cu and Zn to varying levels, especially FeSO·7HO. Al(OH) was required to prevent Cu and Zn mobilization. In this study, 5% FeSO·7HO and 4% Al(OH) mixed with soil was the optimal combination to solve this problem, with Sb, Zn, and Cu stabilizations of 94.6%, 74.2%, and 82.2%, respectively. Column tests spiked with 5% FeSO·7HO, and 4% Al(OH) showed significant Sb (85.85%), Zn (83.9%), and Cu (94.8%) retention. The pH-regulated results indicated that acid conditioning improved Sb retention under alkaline conditions. However, no significant difference was found between the acidification sets and those without pH regulation. The experimental results showed that 5% FeSO·7HO + 4% Al(OH) without pH regulation was effective for the stabilization of Sb and co-occurring metals in primary explosive soils.
原生炸药场地的土壤受到高浓度锑 (Sb) 和共存重金属 (Cu 和 Zn) 的污染,但基本上被忽视了。在这项研究中,我们调查了 Sb 浓度和形态,并研究了联合使用 Fe 和 Fe-Al 基吸附剂对 Sb 和共存金属迁移性的影响。土壤样品中的 Sb 含量从 26.7 到 4255.0 mg/kg 不等。在批量实验中,FeSO 显示出理想的 Sb 吸附(用 10% FeSO·7HO 吸附高达 97%),而 10% Fe 和 10% 针铁矿的吸附率分别为 72%和 41%。然而,Fe 基吸附剂会增强共存 Cu 和 Zn 的迁移能力,程度不同,尤其是 FeSO·7HO。需要 Al(OH)来防止 Cu 和 Zn 的迁移。在这项研究中,5% FeSO·7HO 和 4% Al(OH) 与土壤混合是解决这个问题的最佳组合,Sb、Zn 和 Cu 的稳定率分别为 94.6%、74.2%和 82.2%。用 5% FeSO·7HO 和 4% Al(OH) 进行柱试验表明,Sb(85.85%)、Zn(83.9%)和 Cu(94.8%)的保留率显著。pH 调节结果表明,在碱性条件下,酸化条件可提高 Sb 的保留率。然而,酸化组和未进行 pH 调节的组之间没有发现显著差异。实验结果表明,5% FeSO·7HO + 4% Al(OH) 无需 pH 调节,可有效稳定原生炸药土壤中的 Sb 和共存金属。