砷迁移释放过程中吸附-脱附作用机制的研究进展

高砷地下水污染是一个全球性的环境问题。在特定地质、地貌、气候和水文及水化学条件下,含砷矿物发生吸附-脱附反应,砷元素迁移和释放进入水体,导致高砷地下水生成并危害周围人群健康。本文在系统总结前人研究工作基础上,从吸附质和吸附剂两方面讨论了竞争吸附、氧化还原、pH和有机质等因素对砷吸附-脱附行为的影响,总结得到三种砷吸附-脱附控制机制,即静电吸附机制、离子交换机制和络合形态机制。本文可以为揭示高砷地下水发生机制以及开展砷污染控制和治理提供有益帮助。

Research Advances of the Adsorption-Desorption Mechanism in Arsenic Mobilization and Retention

High arsenic pollution in groundwater is a global environmental issue. Under specific geological, geomorphological, climatic and hydrological and hydrochemical conditions, arsenic-containing minerals undergo adsorption and desorption reactions. Therefore the arsenic was released into groundwater and caused the formation of high arsenic groundwater. Based on the previous researches, this paper analyzed and summarized the mechanism of adsorption-desorption during arsenic migration and intention in groundwater. Effects of competitive adsorption, redox, pH and organic matter on arsenic adsorption-desorption were discussed as adsorbate and adsorbent aspects. Three mechanisms on arsenic adsorption-desorption were summarized, i.e. electrostatic attraction mechanism, ion exchange mechanism and complexation species mechanism. This paper can reveal the occurrence mechanism of high arsenic groundwater and be helpful for arsenic pollution control and treatment.