Mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during high-temperature sintering  

作　　者：Hai-yan Yu Xiao-lin Pan Yong-pan Tian Gan-feng Tu 

机构地区：[1]School of Metallurgy,Northeastern University,Shenyang 110819,China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2020年第7期924-932,共9页矿物冶金与材料学报（英文版）

基　　金：financially supported by the National Key R&D Program of China(No.2018YFC1901903);the National Nature Science Foundation of China(Nos.51674075 and 51774079);the Fundamental Research Funds for the Central Universities,China(No.N182508026)。

摘　　要：The mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during the hightemperature sintering process were systematically investigated using DSC-TG,XRD,SEM-EDS,FTIR,and Raman spectra,and the crystal structure of Na4Ca3(AlO2)10 was also simulated by Material Studio software.The results indicated that the minerals formed during the sintering process included Na4Ca3(AlO2)10,CaO·Al2O3,and 12 CaO·7 Al2O3,and the content of Na4Ca3(AlO2)10 could reach 92 wt%when sintered at 1200°C for 30 min.The main formation stage of Na4Ca3(AlO2)10 occurred at temperatures from 970 to 1100°C,and the content could reach82 wt%when the reaction temperature increased to 1100°C.The crystal system of Na4Ca3(AlO2)10 was tetragonal,and the cells preferred to grow along crystal planes(110)and(210).The formation of Na4Ca3(AlO2)10 was an exothermic reaction that followed a secondary reaction model,and its activation energy was 223.97 kJ/mol.

关 键 词：calcium aluminate sodium oxide crystal structure formation kinetics SINTERING 

分 类 号：TQ132.32[化学工程—无机化工]