Abstract
The kinetics of solid-state oxidation by air of iron, copper and zinc sulfide natural mixture, which is typical of the pyritic copper ores, is investigated. Using the high-temperature X-ray powder diffraction, thermogravimetry and differential scanning calorimetry, it was found that the process can be represented by five exothermic elementary reactions, corresponding to intensive burning of iron, copper and zinc sulfides, and two endothermic ones, associated with decomposition of copper and iron sulfates. Kinetic analysis is performed by Kissinger and Augis–Bennett methods, the model-free function mechanism was determined from y(α) master plots and iterative optimization of the kinetic parameters. The limiting steps of these reactions are nucleation and crystal growth, and the values of activation energy, pre-exponential factor and Avrami exponent are in the ranges of 140–459 kJ·mol–1, 1.41·104–3.49·1031 s–1, and 1.0–1.7, respectively. Crystallization is followed by an increase in the number of nuclei, which may be formed both at the interface and in the bulk of the ore particles, and crystal growth is one-dimensional and controlled by a chemical reaction at the phase boundary or diffusion. The results of the work can contribute to the development of theoretical ideas about the physicochemical transformations of pyritic ores and concentrates during pyrometallurgical operations.
Subject
Materials Chemistry,General Chemical Engineering,General Chemistry
Reference89 articles.
1. Schlesinger ME, King MJ, Sole KC, Davenport WG. Extrac-tive Metallurgy of Copper. 5th Edition. Oxford: Elsevier; 2011.
2. Study of structure and phase composition of copper-cobalt sulfide ores of Dergamyshskoe deposit
3. Trace-elements in sulfides of the Dergamysh cobalt-bearing massive sulfide deposit, the Southern Urals: Mode of occurrence and matter sources
4. Nagaeva SP, Mezentseva OP, Kozorez MV. Mineralogical researches of copper cobalt-containing ores of Dergamysh deposit. Gornyi Zhurnal/Mining J. 2014;11:31–4.
5. Cusano G, Gonzalo MR, Farrell F, Remus R, Roudier S, Del-gado Sancho L. Best Available Techniques (BAT) Reference Document for the main Non-Ferrous Metals Industries, EUR 28648 EN, 902–910.
Cited by
3 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献