Dissolution kinetics and mechanism of gibbsitic bauxite and pure gibbsite in sodium hydroxide solution under atmospheric pressure  

三水铝石矿与纯三水铝石的常压碱溶动力学与溶出机理(英文)

作　　者：杨会宾[1,2] 潘晓林[1] 于海燕[1] 涂赣峰[1] 孙俊民 

机构地区：[1]东北大学材料与冶金学院,沈阳110819 [2]大唐国际高铝煤炭研究开发中心(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：《Transactions of Nonferrous Metals Society of China》2015年第12期4151-4159,共9页中国有色金属学报（英文版）

基　　金：Projects(51104041;51174054;51374065)supported by the National Natural Science Foundation of China;Project(N130402010)supported by the Fundamental Research Funds for the Central Universities;China

摘　　要：The crystal structure, morphology, dissolution kinetics and mechanism of gibbsitic bauxite and pure gibbsite in Na OH solution under atmospheric pressure were systematically investigated by XRD and SEM. The results show that the size of single crystal of gibbsite in gibbsitic bauxite is smaller than that in pure gibbsite, but the interplanar distance is larger than that of pure gibbsite, which result in more defects in the crystal and less energy needed to dissolve in alkaline solution for the gibbsitic bauxite. The dissolution kinetic equations of gibbsitic bauxite and pure gibbsite were established, and the corresponding activation energies were calculated to be 99.144 and 115.149 k J/mol, respectively.结合X射线衍射和扫描电镜技术,对三水铝石矿与纯三水铝石的晶体结构和微观形貌进行对比,并对其在常压和Na OH溶液中的溶出动力学和溶出机理进行系统研究。结果表明,与纯三水铝石相比,铝土矿中三水铝石的单晶颗粒较小,而晶面间距较大。二者上述结构差异性导致矿石中三水铝石晶体缺陷较多,在碱溶液中溶解时需要克服的能量较低。建立三水铝石矿与纯三水铝石的溶出动力学方程,计算得到其溶出表观活化能分别为99.144和115.149 k J/mol。

关 键 词：GIBBSITE crystal structure DISSOLUTION kinetics Bayer process 

分 类 号：TD952[矿业工程—选矿]