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Understanding the reduction behaviors and characteristics of the end products of Fe-Cr-O systems is very important not only for maximizing the recovery of metals from stainless steel dust but also for the subsequent reuse in metallurgical process.The present work first predicted the possible products thermodynamically when FeCr2O4was reduced by C.The reduction behaviors by graphite of three kinds of Fe-Cr-O systems,i.e.,FeCr2O4,Fe2O3+Cr2O3,and Fe+Cr2O3,were then investigated in 1350-1550 C.Further,the microstructures of final products and element distribution conditions were examined.The results suggest that,thermodynamically,the mass of products for the carbothermal reduction of FeCr2O4is a strong function of temperature,and the initial carbon content is used.More Fe-Cr-C solution and less residual carbon content are obtained at higher temperatures and lower nC:nO ratios(the initial molar ratio of C to O in the sample).Experimental data show that the sample amount tends to afect the reduction rate,and the residual carbon content strongly depends on nC:nO.With regard to the phases present in products during the reaction process,metal carbides tend to form in the initial stage,whereas Fe-Cr-C solution forms when the degree of reduction is sufciently high.
Understanding the reduction behaviors and characteristics of the end products of Fe-Cr-O systems is very important not only for maximizing the recovery of metals from stainless steel dust but also for the subsequent reuse in metallurgical process. The present work first predicted the possible products thermodynamically when FeCr2O4was reduced by C. The reduction behaviors by graphite of three kinds of Fe-Cr-O systems, ie, FeCr2O4, Fe2O3 + Cr2O3, and Fe + Cr2O3, were then investigated in 1350-1550 C. Further, the microstructures of final products and element distribution conditions were examined.The results suggest that, thermodynamically, the mass of products for the carbothermal reduction of FeCr2O4is a strong function of temperature, and the initial carbon content is used .More Fe-Cr-C solution and less residual carbon content are obtained at higher temperatures and lower nC: nO ratios (the initial molar ratio of C to O in the sample). Experimental data show that the sample amount tends to afect the r eduction rate, and the residual carbon content strongly depends on nC: nO.With regard to the phases present in products during the reaction process, metal carbides tend to form in the initial stage, while Fe-Cr-C solution forms when the degree of reduction is sufciently high