【摘要】 选取3种砷污染土壤,以草酸钾为提取剂在pH为5.5时解吸污染土壤中的砷,研究了草酸盐从0～10.0mmol·L-1浓度范围内对污染土壤中砷的释放和化学形态的影响.研究结果表明,土壤中砷的释放量随提取时间的增加而增加,在提取时间6h左右砷释放量最大.3价砷、5价砷的释放量随草酸盐浓度的增加而增大,5价砷释放量较3价砷大.同时发现土壤中Fe、Al的共同释放量与砷的释放量存在显著的线性关系.更多还原

【Abstract】 The effect of oxalate on the release of arsenic from three arsenic contaminated soils and the speciation distribution were investigated. Oxalate solution in the concentration range of 0～10.0mmol·L -1 was applied as extractant. The ratio of extractant to soil was 20∶1 (V/W) and the extraction time was 6h. Results showed that oxalate enhanced the release of As (Ⅲ) and As (Ⅴ). Data of co-released Fe and Al indicated that they had linear relationship with the arsenic released. Elevated as released from soils by oxalate was probability due to the decomposition of Fe and Al oxides or hydroxides by oxalate, and then resulted in the release of arsenic from soils.更多还原