【摘要】 制备并表征了α-Fe O(OH),探究了4种低相对分子质量有机酸(LMW)对α-Fe O(OH)吸附As(Ⅲ)的影响,并阐明了机理。单一和混合LMW对α-Fe O(OH)吸附As(Ⅲ)均有抑制作用,4种LMW的影响大小顺序为:草酸(OA)>柠檬酸(CA)>乳酸(LA)、水杨酸(SA)。混合LMW的影响为:OA会加剧CA对α-Fe O(OH)吸附As(Ⅲ)的影响,而SA几乎不起作用。当ρ(As(Ⅲ))较低,LMW通过与α-Fe O(OH)的静电引力、与α-Fe O(OH)表面的铁离子形成配合物、生成沉淀从而影响α-Fe O (OH)对As (Ⅲ)的吸附;当ρ(As(Ⅲ))较高,LMW还通过阻碍As(Ⅲ)在α-Fe O(OH)上的扩散和沉淀作用产生影响。实验结果为土壤中As(Ⅲ)的迁移转化、污染治理提供技术支撑。更多还原

【Abstract】 FeO( OH) was prepared and characterized. The effects of low relative molecular mass organic acids( LMW) in soils on the adsorption of As( Ⅲ) by α-Fe O( OH) were investigated,and the mechanism was elucidated. Single LMW and mixed LMW have inhibitory effect on the adsorption of As( Ⅲ) by α-FeO( OH).The influence order of four LMW on the adsorption of As( Ⅲ) by α-Fe O( OH is as follows: oxalic acid( OA) >citric acid( CA) > lactic acid( LA),salicylic acid( SA). The effect of mixed LMW on the adsorption of As( Ⅲ)by α-Fe O( OH) is as follows: the OA aggravates the effect of CA on the adsorption of As( Ⅲ) by α-Fe O( OH),and addition of SA hardly affects the adsorption of As( Ⅲ) by α-Fe O( OH). When the ρ( As( Ⅲ)) is low,the electrostatic attraction of LMW with α-Fe O( OH),the formation of complexes with iron ions on the surface ofα-Fe O( OH),and the formation of precipitates affect the adsorption of As( Ⅲ) by α-Fe O( OH). When theρ( As( Ⅲ)) is high,the LMW affects the diffusion and precipitation of As( Ⅲ) . The experimental results provide technical support for the migration,transformation,and pollution control of As( Ⅲ) in soil.更多还原