Study on the influence of active oxygen on the natural oxidation of arsenopyrite under different temperature conditions.

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.

Mechanism of arsenic release process from arsenopyrite chemical oxidation.

Oxidation of arsenopyrite is one of the main causes of arsenic pollution in the environment. This study, examind changes in the surface properties of arsenopyrite in the presence of oxygen. Furthermore, X-ray photoelectron spectroscopy, in situ Raman analysis, high-resolution transmission electron microscopy, and ab initio molecular dynamics were carried out on arsenopyrite, and the oxidation properties and processes of the arsenopyrite surface, along with the Fe/As/S oxidation processes, were analysed In situ-Raman spectroscopy data clearly showed that in the presence of oxygen, Fe ions were transformed into Fe ions on the surface of arsenopyrite at 207 cm, and the content of iron oxides on the surface of arsenopyrite increased significantly over time.