Isothermal Coal-Based Reduction Kinetics of Fayalite in Copper Slag.

Autor:	Zhang L; College of Zijin Mining, Fuzhou University, Fuzhou 350116, Fujian, PR China., Zhu Y; College of Zijin Mining, Fuzhou University, Fuzhou 350116, Fujian, PR China., Yin W; College of Zijin Mining, Fuzhou University, Fuzhou 350116, Fujian, PR China.; Fuzhou University-Zijin Mining Group Joint Research Center for Comprehensive Utilization of Mineral Resources, Fuzhou 350116, PR China.; School of Resources & Civil Engineering, Northeastern University, No. 11, Lane Wenhua Road, Shenhe District, Shenyang, Liaoning 110004, PR China., Guo B; College of Zijin Mining, Fuzhou University, Fuzhou 350116, Fujian, PR China., Rao F; College of Zijin Mining, Fuzhou University, Fuzhou 350116, Fujian, PR China., Ku J; College of Zijin Mining, Fuzhou University, Fuzhou 350116, Fujian, PR China.; Fuzhou University-Zijin Mining Group Joint Research Center for Comprehensive Utilization of Mineral Resources, Fuzhou 350116, PR China.
Jazyk:	angličtina
Zdroj:	ACS omega [ACS Omega] 2020 Apr 09; Vol. 5 (15), pp. 8605-8612. Date of Electronic Publication: 2020 Apr 09 (Print Publication: 2020).
DOI:	10.1021/acsomega.9b04497
Abstrakt:	The coal-based reduction of fayalite was characterized using thermogravimetric (TG) and differential TG methods with reduction temperatures from 1123 to 1273 K. The results of fayalite isothermal reduction indicate that the reduction process is divided two stages. The corresponding apparent activation energy E was gained using the isoconversional and model-fitting methods. At the first stage, the effect of temperature on the reduction degree was not clear, and the phase boundary chemical reaction was the controlling step, with an apparent activation energy E value of 175.32-202.37 kJ·mol -1 . At the second stage, when the temperature was more than 1123 K, the conversion degree and the reaction rate increased nonlinearly with increasing temperature, and two-dimensional diffusion, three-dimensional diffusion, one-dimensional diffusion, and phase boundary-controlled reaction were the controlling stages, with an apparent activation energy E ranging from 194.81 to 248.96 kJ·mol -1 . For the whole reduction process, the average activation energy E and pre-exponential factor A were 185.07-225.67 kJ·mol -1 and 0.796-0.797 min -1 , respectively. Competing Interests: The authors declare no competing financial interest. (Copyright © 2020 American Chemical Society.)
Databáze:	MEDLINE
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