Coupled Kinetics of Ferrihydrite Transformation and As(V) Sequestration under the Effect of Humic Acids: A Mechanistic and Quantitative Study

• DOI: 10.1021/acs.est.8b03492
• Publication Date: 2018-09-19T19:34:54Z
• Authors: Shiwen Hu; Yang Lu; Lanfang Peng; Pei Wang; Mengqiang Zhu; Alice C. Dohnalkova; Hong Chen; Zhang Lin; Zhi Dang; Zhenqing Shi
• Keywords: Ferrihydrite; Genetic algorithm

In natural environments, kinetics of As(V) sequestration/release is usually coupled with dynamic Fe mineral transformation, which further influenced by the presence organic matter (NOM). Previous work mainly focused on interactions between and minerals. However, there a lack both mechanistic quantitative understanding kinetic processes in As(V)-Fe mineral-NOM system. this study, we investigated effect humic acids (HA) ferrihydrite transformation into hematite/goethite sequestration Time-resolved HA minerals during were studied using aberration-corrected scanning transmission electron microscopy, chemical extractions, stirred-flow experiments, X-ray absorption spectroscopy. Based experimental results, developed model for fate transformation. Our results demonstrated that rates speciation changes within rates, overall reactions slowed down sorbed able to account variations compositions, solution chemistry, speciation, has significant environmental implications predicting behavior environment.