Reactivity Comparison of Different Ni(II)-Pyrites during Oxidative Dissolution under Acidic and pH-Neutral Conditions

Autor: Shao-Yi Jia, Hai-Tao Ren, Yong-Ling Liu, Bao-Dong Song, Xu Han, Zong-Sheng Liang, Yong Liu, Song-Hai Wu
Rok vydání: 2019
Předmět:
Zdroj: ACS Earth and Space Chemistry. 3:1096-1108
ISSN: 2472-3452
DOI: 10.1021/acsearthspacechem.8b00191
Popis: Natural pyrite has a strong ability to immobilize Ni(II) impurities. However, the differences in the oxidation reactivity between Ni(II)-adsorbed pyrites [Py*-Ni(II)] and Ni(II)-structurally incorporated pyrites [Py-Ni(II)] are still not clearly understood. In this study, Ni(II)-free pyrite (Py-free), Py*-Ni(II), and Py-Ni(II) were prepared, and their oxidation reactivity were compared. Our results show that Ni(II) can be successfully incorporated into the crystalline structure of Py-Ni(II) by replacing structural Fe(II) with the formation of sulfur defects on the surface of Py-Ni(II). The oxidation reactivity of different pyrites depends on how Ni(II) is immobilized in pyrite and follows the order of Py-0.08 > Py-0.02 > Py-free > Py*-Ni(II) [Py-0.02 and Py-0.08 are named according to the Ni(II):Fe(II) molar ratios in the starting material for the synthesis of Py-Ni(II)], indicating that structurally incorporated Ni(II) enhances the oxidation rate of pyrite, whereas adsorbed Ni(II) does the opposite. Diff...
Databáze: OpenAIRE