Non-isothermal decomposition kinetics of hydrogarnet in sodium carbonate solution  

碳酸钠分解水化石榴石的非等温动力学研究（英文）

作　　者：朱小峰 张廷安 王艳秀 吕国志 张伟光 王聪 赵爱春 

机构地区：[1]Key Laboratory of Ecological Utilization of Multi-metal Intergrown Ores of Ministry of Education, School of Materials and Metallurgy, Northeastern University [2]School of Material Science and Engineering, Taiyuan University of Science and Technology

出　　处：《Chinese Journal of Chemical Engineering》2015年第10期1634-1639,共6页中国化学工程学报（英文版）

基　　金：Supported by the Joint Funds of the National Natural Science Foundation of China(U1202274);the National Natural Science Foundation of China(51204040);the Research Fund for the Doctoral Program of Higher Education of China(201200421100 11);the Doctor Start-up Foundation in Taiyuan University of Science and Technology(20142001)

摘　　要：Carbonation decomposition of hydrogarnet is a significant reaction of the calcification-carbonation new method for alumina production by using low-grade bauxite.In this work,non-isothermal decomposition kinetics of hydrogarnet in sodium carbonate solution was studied by high-pressure differential scanning calorimetry(HPDSC) at different heating rates of 2,5,8,10,15 and 20 K·min^(-1),respectively.The activation energy(E_α) was calculated with the help of isoconversional method(model-free),and the reaction mechanism was determined by the differential equation method.The calculated activation energy of this reaction was 115.66 kJ·mol^(-1).Furthermore,the mechanism for decomposition reaction is Avrami-Erofeev(n=1.5),and the decomposition process is diffusion-controlled.Carbonation decomposition of hydrogarnet is a significant reaction of the calcification-carbonation new method for alumina production by using low-grade bauxite.In this work,non-isothermal decomposition kinetics of hydrogarnet in sodium carbonate solution was studied by high-pressure differential scanning calorimetry（HPDSC） at different heating rates of 2,5,8,10,15 and 20 K·min-1,respectively.The activation energy（Eα） was calculated with the help of isoconversional method（model-free）,and the reaction mechanism was determined by the differential equation method.The calculated activation energy of this reaction was 115.66 kJ·mol-1.Furthermore,the mechanism for decomposition reaction is Avrami-Erofeev（n=1.5）,and the decomposition process is diffusion-controlled.

关 键 词：HYDROGARNET Differential scanning calorimetry（DSC） Activation energy Mechanism function CARBONATION ALUMINA 

分 类 号：TF821[冶金工程—有色金属冶金]