Thermal roasting behavior and kinetics of African cobalt-rich copper sulfide ore in air atmosphere

Abstract African cobalt-rich copper sulfide ore (CRCS) is an important copper-cobalt resource. The CRCS mainly contains chalcopyrite ($ CuFeS_{2} $), pyrite ($ FeS_{2} $), and carrollite ($ CuCo_{2} %$ S_{4} $). In our previous study, activated roasting was used to treat CRCS, converting $ CuCo_{2}...
Ausführliche Beschreibung

Abstract African cobalt-rich copper sulfide ore (CRCS) is an important copper-cobalt resource. The CRCS mainly contains chalcopyrite ($ CuFeS_{2} $), pyrite ($ FeS_{2} $), and carrollite ($ CuCo_{2} %$ S_{4} $). In our previous study, activated roasting was used to treat CRCS, converting $ CuCo_{2} %$ S_{4} $ into sulfate that is easy to leach Cu and Co. It was found that the kinetics of $ CuCo_{2} %$ S_{4} $ in CRCS transformation was slow during roasting, which is a key factor affecting the subsequent increase in cobalt leaching rate. Therefore, it is of practical significance to explore the kinetics process in the activated roasting process of CRCS. In this study, thermal roasting kinetics of CRCS in the air atmosphere was studied by TG-DTG method at heating rates of 5, 10, 15, and 20 K $ min^{−1} $, respectively. Meanwhile, the phase transformation behavior of major minerals, pyrite, and carrollite during roasting was studied. The results show that the roasting process of CRCS mainly goes through three stages: Stage I: removal of free water and crystal water; Stage II: oxidation of sulfide minerals to sulfate; and Stage III: decomposition of sulfate to oxide. Given Stage II, the deconvolution separation method was used to separate overlapping reaction peaks of $ FeS_{2} $ and $ CuCo_{2} %$ S_{4} $. The kinetic parameters were evaluated by Friedman method, KAS method, FWO method, and CR method, respectively. The most probable mechanism function and activation energy (E) were determined by comparing the model-free method with the model-fitting method. Results showed that the oxidation of $ FeS_{2} $ in CRCS conforms to the 2-D diffusion model; the oxidation of $ CuCo_{2} %$ S_{4} $ in CRCS accords with the Avrami–Eroféev model. Finally, thermodynamic parameters of the reaction including enthalpy, entropy, and Gibbs free energy were calculated. Kinetic analysis shows that the heating rate has a significant influence on the ore phase transition during the oxidation process of CRCS. The oxidation processes of different ore in CRCS conform to different kinetic mechanisms. Ausführliche Beschreibung

Autor*in:	Yang, Weijiao [verfasserIn] Li, Xiang Liu, Yubo Ma, Baozhong Wang, Hua Jiang, Xingming Wang, Chengyan

Format:	E-Artikel
Sprache:	Englisch

Erschienen:	2022

Schlagwörter:	African cobalt-rich copper sulfide ore Thermal roasting kinetics Roasting behavior Deconvolution integral separation Sulfating reaction

Anmerkung:	© Akadémiai Kiadó, Budapest, Hungary 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Übergeordnetes Werk:	Enthalten in: Journal of thermal analysis and calorimetry - Dordrecht [u.a.] : Springer Science + Business Media B.V., 1969, 147(2022), 23 vom: 08. Okt., Seite 13469-13481
Übergeordnetes Werk:	volume:147 ; year:2022 ; number:23 ; day:08 ; month:10 ; pages:13469-13481

Links:	Volltext

DOI / URN:	10.1007/s10973-022-11628-6

Katalog-ID:	SPR048720690