利用非晶质的铁氧羟硫酸盐水合物固定污染土壤中的砷。
Arsenic immobilization in the contaminated soil using poorly crystalline Fe-oxyhydroxy sulfate.
机构信息
School of Metallurgy and Environment, Central South University, Changsha, 410083, China.
出版信息
Environ Sci Pollut Res Int. 2015 Aug;22(16):12624-32. doi: 10.1007/s11356-015-4455-1. Epub 2015 Apr 26.
A low crystalline Fe-oxyhydroxy sulfate (FeOS) was used to immobilize arsenic (As) in soils in this study. The effects of FeOS amount, treatment time and soil moisture on As immobilization were investigated. The results showed that water-soluble and NaHCO3-extractable As were immobilized by 53.4-99.8 and 13.8-73.3% respectively, with 1-10% of FeOS addition. The highest immobilization of water-soluble (98.5%) and NaHCO3-extractable arsenic (47.2%) was achieved under condition of 4% of FeOS and 80% of soil moisture. Further, more amounts of FeOS addition resulted in less time requirement for As immobilization. Sequential chemical extraction experiment revealed that easily mobile arsenic phase was transferred to less mobile phase. The FeOS-bonded As may play a significant role in arsenic immobilization. Under leaching with simulated acid rain at 60 times pore volumes, accumulation amount of As release from untreated soil and soil amended with FeOS were 98.4 and 1.2 mg, respectively, which correspond to 7.69 and 0.09% of total As amounts in soil. The result showed that the low crystalline FeOS can be used as a suitable additive for arsenic immobilization in soils.
本研究采用低结晶态的铁氧羟硫酸铁（FeOS）来固定土壤中的砷。考察了 FeOS 用量、处理时间和土壤湿度对砷固定的影响。结果表明，添加 1%-10%的 FeOS 可使土壤中 53.4%-99.8%的水溶态砷和 13.8%-73.3%的 NaHCO3 可提取态砷得以固定。当 FeOS 添加量为 4%，土壤湿度为 80%时，水溶态砷（98.5%）和 NaHCO3 可提取态砷（47.2%）的固定率最高。进一步增加 FeOS 添加量可以减少砷固定所需的时间。连续化学提取实验表明，易迁移的砷相被转化为更难迁移的相。FeOS 结合的砷可能在砷固定中起重要作用。在 60 倍孔隙体积的模拟酸雨淋洗下，未经处理土壤和添加 FeOS 的土壤中砷的累积释放量分别为 98.4 和 1.2mg，分别占土壤总砷量的 7.69%和 0.09%。结果表明，低结晶态 FeOS 可用作土壤中砷固定的合适添加剂。
Zotero 插件