Powder iron monosilicide with certain structure exhibits magnetic properties and can be used as an alloying additive in the production of electrical steels and silicon alloys with special physical and chemical propert...Powder iron monosilicide with certain structure exhibits magnetic properties and can be used as an alloying additive in the production of electrical steels and silicon alloys with special physical and chemical properties. From this point of view, development of the energy-saving technology for receiving such a valuable alloying agent with the disposal of secondary waste is an urgent task. For this purpose, the method of joint aluminothermic reduction of preliminary mechanically activated metallurgical waste is offered. Recently, a method for combining the self-propagating high-temperature synthesis and preliminary mechanical activation for obtaining metal powders with certain phase composition and structure is considered as one of the efficient ones. As the initial materials for obtaining iron monosilicide, the waste (or converter) slags of the Alaverdi copper-smelting plant and molybdenum slags of the Yerevan Pure Iron Plant are used. Besides the mentioned slags, NaNO<sub>3</sub> and CaO are added. Properties and structure of the received silicide depend on the contents, quantity of components, and the mass relation of two wastes in the burden. Therefore, the processes of structure formation of the iron monosilicide received from metallurgical waste are investigated. Studies have shown that the best results are obtained in case of waste and molybdenum slag relation of 4:1, when the 60-minute grinding in the vibromill leads to a significant increase in the mechanical activation of the burden. At this relation of FeO and SiO2, a condition is created for receiving iron monosilicide showing magnetic properties. On the whole, those transformations lead to a decrease in the reaction activation power of the interacting substances, an increase of the reactivity capacities, as well as to a new original course of reactions and new modified materials.展开更多
文摘Powder iron monosilicide with certain structure exhibits magnetic properties and can be used as an alloying additive in the production of electrical steels and silicon alloys with special physical and chemical properties. From this point of view, development of the energy-saving technology for receiving such a valuable alloying agent with the disposal of secondary waste is an urgent task. For this purpose, the method of joint aluminothermic reduction of preliminary mechanically activated metallurgical waste is offered. Recently, a method for combining the self-propagating high-temperature synthesis and preliminary mechanical activation for obtaining metal powders with certain phase composition and structure is considered as one of the efficient ones. As the initial materials for obtaining iron monosilicide, the waste (or converter) slags of the Alaverdi copper-smelting plant and molybdenum slags of the Yerevan Pure Iron Plant are used. Besides the mentioned slags, NaNO<sub>3</sub> and CaO are added. Properties and structure of the received silicide depend on the contents, quantity of components, and the mass relation of two wastes in the burden. Therefore, the processes of structure formation of the iron monosilicide received from metallurgical waste are investigated. Studies have shown that the best results are obtained in case of waste and molybdenum slag relation of 4:1, when the 60-minute grinding in the vibromill leads to a significant increase in the mechanical activation of the burden. At this relation of FeO and SiO2, a condition is created for receiving iron monosilicide showing magnetic properties. On the whole, those transformations lead to a decrease in the reaction activation power of the interacting substances, an increase of the reactivity capacities, as well as to a new original course of reactions and new modified materials.
基金the financial supports from the National Key Research and Development Plan of China(No.2021YFC2902801)the National Natural Science Foundation of China(Nos.52064034,51664038)。
文摘开展硫化锌精矿还原浸出高铁锌浸出渣高效浸铟及浸出液中铟选择性分离的研究。结果表明:在固体物料粒度74~105μm、反应温度90℃、浸出时间300 min、硫酸浓度1.4 mol/L的条件下,铟的浸出率达95%以上。采用收缩核模型对还原浸出动力学进行分析,不同条件下的浸出实验结果表明反应受穿过固体产物层的扩散控制,活化能为17.96 k J/mol,相对于硫酸浓度的反应级数为2.41。铁粉置换沉铜过程铜和砷的沉淀率均达99%以上。98%以上的铟从含高亚铁离子浓度的硫酸锌溶液中选择性分离,获得铟含量约为2.4%的富铟渣,经酸浸-萃取-电积工艺流程进一步处理后可得到纯铟。