活性硅酸钙高温相变历程研究  

High-temperature Phase Change of Active Calcium Silicate

作　　者：洪景南 孙俊民 许学斌 杨会宾 李运改 

机构地区：[1]大唐国际高铝煤炭资源开发利用研发中心,鄂尔多斯010321 [2]国家能源高铝煤炭资源开发利用重点实验室,鄂尔多斯010321

出　　处：《硅酸盐通报》2016年第3期736-742,747,共8页Bulletin of the Chinese Ceramic Society

基　　金：国家高技术研究发展计划(863计划)(2011AA6A101)

摘　　要：通过TGA/DSC、XRD、FTIR、SEM等测试手段,对高铝粉煤灰提取氧化铝副产物-活性硅酸钙在各温度区间的相变历程进行系统研究。TGA/DSC结果表明活性硅酸钙结构中有5个结晶水,160℃时开始逐渐失去结晶水,600℃前结晶水脱除完毕,672℃时部分Si-O-H键断裂,失去羟基。XRD和FTIR结果表明700℃时活性硅酸钙结构已破坏,衍射峰消失,转变为无定形的非晶态;700~800℃时发生晶型转变,结构开始转变为有序的硅灰石晶体结构;1100℃时完全转变为低温型2M型硅灰石结构;1300℃时完全转变为高温型假硅灰石结构。活性硅酸钙的高温相变经历了＂活性硅酸钙→脱水硅酸钙→脱羟基硅酸钙→2M型硅灰石→假硅灰石＂的转变历程。The different temperature range phase transition of active calcium silicate was investigated by TGA / DSC,XRD,SEM and FTIR,active calcium silicate is the extraction of aluminium oxide from high alumina fly ash’s by-product. The TGA / DSC results showed that active calcium silicate have five crystal water,beginning lost crystal water at 160 ℃,five crystal water were lost when they were heated at 600℃,Si-O-H bonds were fractured and dehydroxylation at 672 ℃. The XRD and FTIR results showed that X-ray diffraction of active calcium silicate disappeared and the crystal structure was broken at 700 ℃,the crystal structure transformed to be amorphous. The disordered structure recombined to wollastonite when the calcination temperature between at 700-800 ℃,the crystal structure became ordered. The structure completely transformed to 2M-wollastonite at 1100 ℃. Finally,the structure completely transformed to pseudowollastonite at 1300 ℃. It should include the process of high-temperature phase transition of active calcium silicate： active calcium silicate→dehydration calcium silicate→dehydroxylation calcium silicate→2M-wollastonite→pseudowollastonite.

关 键 词：活性硅酸钙 高温相变 硅灰石 假硅灰石 

分 类 号：TD98[矿业工程—选矿]