黄铵铁矾渣热分解反应机理及其动力学解析  

Thermal decomposition reaction and kinetic analysis of ammonium jarosite residues

作　　者：崔雅茹[1] 李邓 王国华 李小明[1] 赵俊学[1] 王正民 桂海平 CUI Yaru;LI Deng;WANG Guohua;LI Xiaoming;ZHAO Junxue;WANG Zhengmin;GUI Haiping(School of Metallurgical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Hanzhong Zinc Industry Co.,Ltd.,Hanzhong 724204,China)

机构地区：[1]西安建筑科技大学冶金工程学院,西安710055 [2]汉中锌业有限责任公司,汉中724204

出　　处：《中国有色金属学报》2024年第7期2452-2462,共11页The Chinese Journal of Nonferrous Metals

基　　金：陕西省科技厅重点研发计划资助项目(2022GY-160);陕西省博士后科研资助项目(2023BSHEDZZ275)。

摘　　要：针对黄铵铁矾渣侧吹熔炼熔渣稳定控制研究需求,采用热重−差热−质谱联用仪结合XRD、SEM-EDS等分析方法对其热分解过程及动力学特性进行研究。结果表明:黄铵铁矾渣中主要化合物为铵铁矾(NH_(4))Fe_(3)(SO_(4))_(2)(OH)_(6)、铁锌尖晶石(Zn,Fe)Fe_(2)O_(4)及硫酸铅PbSO_(4)、CaSO_(4)(H_(2)O)_(2)等硫酸盐。在热分解过程中,铵铁矾在380℃左右发生了脱氨、脱羟反应,生成各种硫酸盐,其机理函数为减速型α−t曲线;Fe_(2)(SO_(4))3在610℃时发生了分解,反应表观活化能E为153.07 kJ/mol,强化气体产物的扩散有助于推进反应进程;硫酸铅在1080℃左右发生分解,其反应机理遵循三维扩散,表观活化能较高(555.90 kJ/mol);硫酸铅分解的主要限制性因素是分解产物PbO在渣中的扩散,可通过降低渣系的熔点及黏度促进反应进行。To meet the demand of process stability control in side-blowing smelting for treating ammonium jarosite residues,the thermal decomposition and kinetic characteristics of the ammonium jarosites were investigated by means of TG-DSC-MS combined with XRD and SEM-EDS analysis.The results show that the main phases discovered in the researched slag are those of ammonium jarosite(NH_(4))Fe_(3)(SO_(4))_(2)(OH)_(6),spinel(Zn,Fe)Fe_(2)O_(4),sulfates of PbSO_(4) and CaSO_(4)(H_(2)O)_(2).During thermal decomposition,the dehydroxylation and deamination reaction occur at about 380℃,resulting in various sulfates,the mechanism function of the dehydroxylation-deamination reaction is the deceleratingα−t curve.In addition,the decomposition of Fe_(2)(SO_(4))3 occurs at about 610℃,with a corresponding activation energy of 153.07 kJ/mol,which means strengthening the diffusion of gaseous product may contribute to the reaction.And the decomposition of PbSO_(4) occurs at about 1080℃with a high activation energy of 555.90 kJ/mol,whose reaction kinetic mechanism follows the three-dimensional diffusion.The main limiting factor of PbSO_(4) decomposition depends upon the diffusion of PbO product in the slag,which can be promoted by reducing the melting temperature and viscosity of the slag system.

关 键 词：黄铵铁矾渣 热分解 反应机理 动力学特性 表观活化能 

分 类 号：TF813[冶金工程—有色金属冶金]