Arsenic (As), a toxic element, contaminates farmlands, rivers, and groundwater, posing severe environmental and health risks. Notably, As-containing materials in tailings are affected by temperature variations during long-term storage, and this considerably impact the oxidation and migration of elements in arsenopyrite.This study focused on arsenopyrite and investigated the process of its oxidative dissolution and release of arsenic under different temperature conditions by using in-situ XRD, in-situ XPS and electron paramagnetic resonance spectroscopy(EPR), The role of oxygen free radicals in the oxidation of arsenopyrite was elucidated. It has been established that under high-temperature conditions As, iron (Fe), and sulfur (S) are primarily present As(V)/As(IV), Fe(III), and SO, respectively. The O generated during the oxidation of As(III) by O, OH produced by the Fe(II)/FeOH reaction, and HO formed via their interaction play a crucial role in the photochemical oxidation of arsenopyrite. These findings provide a theoretical basis for the formation of ferric arsenate precipitation, contributing in the adsorption and immobilisation of oxidatively released arsenic.
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http://dx.doi.org/10.1016/j.jhazmat.2024.135420 | DOI Listing |
J Hazard Mater
December 2024
School of Minerals Processing and Bioengineering, Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China. Electronic address:
The oxidative dissolution of arsenopyrite (FeAsS) is a significant source of arsenic contamination in nature. Activated biochar (AC), a widely used environmental remediation agent, is prevalent in ecosystems and participated in various geochemical processes of arsenic and iron-containing sulfide minerals. However, the impact of AC-arsenopyrite association on reactive oxidation species (ROS) generation and its contribution to As transformation were rarely explored.
View Article and Find Full Text PDFJ Hazard Mater
October 2024
Guangxi Science & Technology Normal University, Laibin 546100, China.
Arsenic (As), a toxic element, contaminates farmlands, rivers, and groundwater, posing severe environmental and health risks. Notably, As-containing materials in tailings are affected by temperature variations during long-term storage, and this considerably impact the oxidation and migration of elements in arsenopyrite.This study focused on arsenopyrite and investigated the process of its oxidative dissolution and release of arsenic under different temperature conditions by using in-situ XRD, in-situ XPS and electron paramagnetic resonance spectroscopy(EPR), The role of oxygen free radicals in the oxidation of arsenopyrite was elucidated.
View Article and Find Full Text PDFWater Res
September 2024
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, PR China. Electronic address:
Serious arsenic (As) contaminations could commonly result from the oxidative dissolution of As-containing sulfide minerals, such as arsenopyrite (FeAsS). Pyrite (Py) and calcite (Cal) are two typically co-existing reactive minerals and represent different geological scenarios. Previous studies have shown that a high proportion of Py can generate a stronger galvanic effect and acid dissolution, thereby significantly promoting the release of arsenic.
View Article and Find Full Text PDFJ Hazard Mater
July 2024
State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China.
The arsenopyrite activated by copper ions have similar flotation properties to chalcopyrite. Polyaspartic acid (PASP) and calcium oxide (CaO) using as combination depressants for the selective separation of copper-activated arsenopyrite and chalcopyrite were carried out by micro-flotation experiments, contact angle measurements, surface adsorption capacity tests, zeta potential measurements, X-ray photoelectron spectroscopy (XPS) analyses, inductively coupled plasma-optical emission spectrometer (ICP-OES) tests and time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses, and its depression mechanism was investigated. The results of flotation experiments showed that the recovery of arsenopyrite after addition of the depressants reached only 7.
View Article and Find Full Text PDFMolecules
March 2024
School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.
The increasing presence of arsenic-containing impurities within Cu ores can adversely affect the smelting process and aggravate the environmental impact of slag tailing. This study investigates the geochemical, mineralogical, and chemical speciation characteristics to better understand the association and environmental stability of metal(loid)s in copper slag tailing. The results indicate that the predominant chemical compositions of the selected slag tailing are FeO (54.
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