Investigation on the performance and mechanism of Cr(VI) immobilization with improved amorphous iron polysulfide: Batch experiments and numerical simulation

IF 3.1 3区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Applied Geochemistry Pub Date : 2025-03-13 DOI:10.1016/j.apgeochem.2025.106357

Kelin Zhang , Danqing Liu , Jinhao Yu , Changzhong Xu , Yilian Li

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引用次数: 0

Abstract

Amorphous iron sulfides (FeS_x), which are more powerful than crystalline FeS_x in reduction, are commonly found on the surfaces of many sulfidated nanoscale zero-valent iron (nZVI). However, due to the interference of nZVI, the reduction performance of FeS_x is still unknown. In this paper, we synthesized efficient amorphous iron polysulfide (AIPS) with FeSO₄ and CaS_x and checked its reduction ability using Cr(VI) as a model contaminant, and found that the reactivity and amorphous structure of AIPS were significantly affected by the titration rate of CaS_x during synthesis. The removal of Cr(VI) by AIPS synthesized at a titration time of 120 min was 81.9 mg/g, which was 10.6 times higher than that of AIPS synthesized within 6 min (7.7 mg/g). The improved AIPS can be applicable for Cr(VI) removal via simultaneous adsorption, reduction and precipitation at wide pH range and in the coexistence of ionic and natural organic matter (NOM). Using a reactive transport model, it can be found that FeS and FeS₂ in AIPS contribute 85.01 % and 14.99 % to the Cr(VI) reduction, respectively. FeS_x (x > 2), also as a reaction by-product of the Cr(VI) reduction by FeS and FeS₂, hinders the reduction of Cr(VI).

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来源期刊

Applied Geochemistry 地学-地球化学与地球物理

CiteScore

6.10

自引率

8.80%

发文量

272

审稿时长

65 days

期刊介绍： Applied Geochemistry is an international journal devoted to publication of original research papers, rapid research communications and selected review papers in geochemistry and urban geochemistry which have some practical application to an aspect of human endeavour, such as the preservation of the environment, health, waste disposal and the search for resources. Papers on applications of inorganic, organic and isotope geochemistry and geochemical processes are therefore welcome provided they meet the main criterion. Spatial and temporal monitoring case studies are only of interest to our international readership if they present new ideas of broad application. Topics covered include: (1) Environmental geochemistry (including natural and anthropogenic aspects, and protection and remediation strategies); (2) Hydrogeochemistry (surface and groundwater); (3) Medical (urban) geochemistry; (4) The search for energy resources (in particular unconventional oil and gas or emerging metal resources); (5) Energy exploitation (in particular geothermal energy and CCS); (6) Upgrading of energy and mineral resources where there is a direct geochemical application; and (7) Waste disposal, including nuclear waste disposal.