简介:The pH has a significant impact on arsenic (As) removal by nano zero valent iron (nZVI). However, most studies consider the influence mechanism just from the aspect of electrostatic interactions. In this study, based on 简介:The pH has a significant impact on arsenic (As) removal by nano zero valent iron (nZVI). However, most studies consider the influence mechanism just from the aspect of electrostatic interactions. In this study, based on the different As(V) adsorption capacity of nZVI and zero valent iron (ZVI) after normalization by specific surface area, we deeply analyze the comprehensive mechanism of arsenic adsorption by nZVI at varying pH values. Batch experiment shows that pH variation has a weaker influence on the As(V) adsorption by nZVI compared to ZVI. X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES) analysis indicated that with the coexistence of low concentration As(V) species, the increasing pH value condition does not significantly change the phase of ZVI; however, it decreases the lepidocrocite (γ-FeOOH) and increases the magnetite/maghemite (Fe3O4/γ-Fe2O3) content in the corrosion products of nZVI, while the latter has stronger adsorption affinity to As(V). 详细>