铁尾矿复合陶瓷的制备及远红外发射性能研究

发布时间：2018-05-03 02:37

  本文选题：铁尾矿 + 功能材料　； 参考：《河北工业大学》2015年博士论文

【摘要】：远红外功能陶瓷常以过渡金属氧化物、氧化锆、石英、堇青石等为主要原料制成,在节能、人体保健等领域具有广阔应用前景。本工作以铁尾矿为主要研究对象,通过优化陶瓷的配料体系和烧成制度,制备具有红外发射性能的铁尾矿复合陶瓷材料,研究其红外发射机制及影响因素,为铁尾矿资源的高附加值功能化利用探索新途径。通过铁尾矿化学成分的分析,确定铁尾矿、碳酸钙、二氧化硅为远红外陶瓷的配方体系,并分别以电气石和稀土为添加剂进一步提高陶瓷的红外发射性能。配方中铁尾矿、碳酸钙、二氧化硅三者的质量比为6:1:1。电气石复合铁尾矿陶瓷的烧结温度为1065~1070℃,熔融温度为1075~1081℃;稀土复合铁尾矿陶瓷的烧结温度为1062~1070℃,熔融温度为1065~1075℃。利用热重-差热、高温物性分析方法研究添加剂对铁尾矿陶瓷烧结的影响。随着电气石含量的增加,陶瓷的密度由1.68 g/cm3增大到1.96 g/cm3,烧结温度由1070℃降低到1065℃。随着稀土含量的增加,陶瓷的密度由1.65 g/cm3增大到1.79 g/cm3,烧结温度由1070℃降低到1062℃。利用Kissinger法计算得到电气石复合铁尾矿陶瓷中碳酸盐分解的活化能为209.39~233.37 kJ/mol,陶瓷烧结的活化能为101.79~174.36 kJ/mol。稀土复合铁尾矿陶瓷中碳酸盐分解的活化能为191.53~223.41 kJ/mol,陶瓷烧结的活化能为96.880~164.16 kJ/mol。电气石和稀土有利于加快烧结反应速率,促进铁尾矿陶瓷的烧结。从晶体微观结构和化学键振动两方面分析电气石和稀土促进铁尾矿陶瓷红外发射的机制。随着电气石含量的增加,陶瓷的红外发射率先增大后减小,添加5 wt.%电气石时,陶瓷的红外发射率最高达0.925。电气石晶体结构中的Fe2+通过取代辉石中的Ca2+形成类质同象结构,增强辉石中Ca-O键的振动,进而促进铁尾矿陶瓷红外发射率的提高。随着稀土含量的增加,陶瓷的红外发射率同样呈现先增大后减小的变化趋势,添加7 wt.%稀土时,陶瓷的红外发射率最高达0.914。稀土Ce4+通过与铁透辉石形成间隙固溶体,增强铁透辉石中八面体处Mg-O键和四面体处Fe-O键的振动,进而提高陶瓷的红外发射性能。
[Abstract]:The far-infrared functional ceramics are usually made from transition metal oxides, zirconia, quartz, cordierite and so on. In this work, the iron tailings composite ceramic materials with infrared emission properties were prepared by optimizing the ceramic batching system and sintering system, and the infrared emission mechanism and influencing factors were studied. To explore a new way for the utilization of high added value function of iron tailings. Based on the analysis of the chemical composition of iron tailings, the formula system of iron tailings, calcium carbonate and silicon dioxide was determined, and the infrared emission properties of the ceramics were further improved by using tourmaline and rare earth as additives, respectively. The mass ratio of iron tailings, calcium carbonate and silica is 6: 1: 1. The sintering temperature and melting temperature of tourmaline composite iron tailings ceramics and rare earth composite iron tailings ceramics are 1065 ~ 1070 鈩，

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