As alkali additive,KC1 catalyzes effectively the carbothermic reduction of pre-oxidized ilmenite,and the catalytic effect becomes more remarkable as the amount of KC1 increases.During the carbothermic reduction,the ga...As alkali additive,KC1 catalyzes effectively the carbothermic reduction of pre-oxidized ilmenite,and the catalytic effect becomes more remarkable as the amount of KC1 increases.During the carbothermic reduction,the gaseous product consists mainly of CO,and the partial pressure of which increases with reaction temperature.The EPMA and XPS of the partially reduced ilmenite ore and that of the used graphite as reductant showed that the potassium ions enter both ilmenite particles and graphite powders during reduction.The above-mentioned phenomena result in the distortion of ilmenite and carbon structure by potassium ions and reaction activity of carbon and ilmenite was enhanced.As a result,the overall carbothermic reduction was catalyzed by KC1.展开更多
Reduction behavior of preoxidized synthetic ilmenite was studied by means of Mossbauer spectra. In the course of reduction, iron component in the samples is reduced in stepwise: Fe 3+ →Fe 2+ →Fe 0, and some...Reduction behavior of preoxidized synthetic ilmenite was studied by means of Mossbauer spectra. In the course of reduction, iron component in the samples is reduced in stepwise: Fe 3+ →Fe 2+ →Fe 0, and some intermediate compounds, such as Fe 3O 4, Fe 2TiO 4 etc . and their solid solution may be generated besides Fe 2O 3 and FeTiO 3. If the reduction temperature is higher than 1173 K, the metallization needs only half time of the case when the temperature is lower than 1073 K.展开更多
基金Item Sponsored by National Natural Science Foundation(59774026)
文摘As alkali additive,KC1 catalyzes effectively the carbothermic reduction of pre-oxidized ilmenite,and the catalytic effect becomes more remarkable as the amount of KC1 increases.During the carbothermic reduction,the gaseous product consists mainly of CO,and the partial pressure of which increases with reaction temperature.The EPMA and XPS of the partially reduced ilmenite ore and that of the used graphite as reductant showed that the potassium ions enter both ilmenite particles and graphite powders during reduction.The above-mentioned phenomena result in the distortion of ilmenite and carbon structure by potassium ions and reaction activity of carbon and ilmenite was enhanced.As a result,the overall carbothermic reduction was catalyzed by KC1.
文摘Reduction behavior of preoxidized synthetic ilmenite was studied by means of Mossbauer spectra. In the course of reduction, iron component in the samples is reduced in stepwise: Fe 3+ →Fe 2+ →Fe 0, and some intermediate compounds, such as Fe 3O 4, Fe 2TiO 4 etc . and their solid solution may be generated besides Fe 2O 3 and FeTiO 3. If the reduction temperature is higher than 1173 K, the metallization needs only half time of the case when the temperature is lower than 1073 K.
