Carbothermic reduction kinetics of ilmenite concentrates catalyzed by sodium silicate and microwave-absorbing characteristics of reductive products

Wei Li, Jinhui Peng, Shenghui Guo, Libo Zhang, Guo Chen, Hongying Xia
2013 Chemical Industry and Chemical Engineering Quarterly  
Carbothermic reduction kinetics of ilmenite concentrates catalyzed by sodium silicate were investigated; the reduction degree of ilmenite concentrates reduction reaction was determined as R = 4/7(16y + 56x)(ΔW Σ -f A-P W)/(16y + + 56x + 112). The results show that the reaction activation energy of initial stage and later stage is 36.45 and 135.14 kJ/mol, respectively. There is a great change in the reduction rate at temperatures of 1100 and 1150 °C; the catalysis effect and change of reduction
more » ... hange of reduction rate were evaluated by TG and DSC curves of sodium silicate. Microwave-absorbing characteristics of reduction products were measured by the method of microwave cavity perturbation. It was found that microwave absorbing characteristics of reduction products obtained at temperatures of 900, 1100 and 1150 °C have significant differences. XRD characterization results explained the formation and accumulation of reduction product Fe, and pronounced changes of microwave absorbing characteristics due to the decrease of the content of ilmenite concentrates.
doi:10.2298/ciceq120421077l fatcat:3jni3wuatzbbflcyf4qzkkntha