Reaction behaviour of Al_2O_3 and SiO_2 in high alumina coal fly ash during alkali hydrothermal process

作     者：蒋周青 杨静 马鸿文 王乐 马玺 Zhou-qing JIANG;Jing YANG;Hong-wen MA;Le WANG;Xi MA

作者机构：中国地质大学(北京)材料科学与工程学院北京100083 昊青薪材(北京)技术有限公司北京100083 

出 版 物：《Transactions of Nonferrous Metals Society of China》 (中国有色金属学报（英文版）)

年 卷 期：2015年第25卷第6期

页      面：2065-2072页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 

基　　金：Project(2652014017) supported by the Fundamental Research Funds for the Central Universities China 

主　　题：high alumina coal fly ash A1203 SiO2 alkali hydrothermal treatment reaction behaviour 

摘      要：The reaction behaviours of A1203 and SiO2 in high alumina coal fly ash under various alkali hydrothermal conditions were studied. The means of XRD, XRF, FTIR and SEM were used to measure the mineral phase and morphology of the solid samples obtained by different alkali hydrothermal treatments as well as the leaching ratio of SiO2 to A1203 in alkali solution. The results showed that with the increase of the hydrothermal treating temperature from 75 to 160 ~C, phillipsite-Na, zeolite A, zeolite P, and hydroxysodalite were produced sequentially while the mullite and corundum phase still remained. Zeolite P was massively formed at low-alkali concentration and the hydroxysodalite was predominantly obtained at high-alkali concentration. By the dissolution of aluminosilicate glass and the formation of zeolites together, the leaching efficiency of SiO2 can reach 42.13% with the mass ratio of A1203/SIO2 up to 2.19：1.