铵盐浸取风化壳淋积型稀土矿中稀土和铝的动力学研究  

Kinetics of leaching rare earth and aluminum from weathered crust elution-deposited rare earth ore with ammonium salts

作　　者：何正艳[1] 周洁 左琴 沙傲阳 常丽嘉 徐志高[1] 池汝安 吴明 HE Zheng-yan;ZHOU Jie;ZUO Qin;SHA Ao-yang;CHANG Li-jia;XU Zhi-gao;CHI Ru-an;WU Ming(Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission,South-central University for Nationalities,Wuhan 430074,China;Laboratory for Green Chemical Process of Ministry of Education,Wuhan Institute of Technology,Wuhan 430073,China)

机构地区：[1]中南民族大学资源转化与污染控制国家民委重点实验室,湖北武汉430074 [2]武汉工程大学绿色化工过程教育部重点实验室,湖北武汉430073

出　　处：《高校化学工程学报》2021年第4期665-674,共10页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(U2002215,51734001);中南民族大学中央高校基本科研业务费专项资金(YZZ16002)。

摘　　要：为了探究铵盐浸取剂的使用,揭示稀土和杂质的浸出规律,以硫酸铵、氯化铵和硝酸铵分别作为浸取剂,考察温度、铵根离子浓度和流速对风化壳淋积型稀土矿中稀土和铝浸出动力学的影响,并采用收缩未反应芯模型对浸出过程进行拟合。结果表明,在一定范围内提高温度、铵根离子浓度或流速均可提高稀土和铝的浸出速率。硫酸铵浸出速率最慢、氯化铵次之,硝酸铵最快,且铝的浸出速率均略慢于稀土。稀土和铝的浸出过程受内扩散控制,浸取反应活化能大小依次为硫酸铵>氯化铵>硝酸铵,稀土<铝。浸取反应活化能越大,表观速率常数越低,反应级数越高。该结果可为风化壳淋积型稀土矿的高效开采提供理论指导。The leaching experiments of rare earth and impurities was carried out using ammonium salts as leaching agents.The effects of temperature,ammonium ion concentration and flow rate on the leaching kinetics of rare earth and aluminum in weathered crust elution-deposited rare earth ore were studied using ammonium sulfate,ammonium chloride and ammonium nitrate as leaching agents respectively.The leaching kinetics was developed based on the shrinking unreacted core model and fitted by experiment results.The results showed that the leaching rates of rare earth and aluminum increased with increasing temperature,ammonium ion concentration or flow rate within a certain range.The leaching rate was the slowest when using ammonium sulfate as leaching agents,and the fastest when using ammonium nitrate.The leaching rate of aluminum was slightly slower than that of rare earth.The leaching process of rare earth and aluminum was controlled by the inter-diffusion.The order of activation energy of leaching reaction was ammonium sulfate>ammonium chloride>ammonium nitrate and rare earth<aluminum.The larger the leaching reaction activation energy,the smaller the apparent rate constant and the higher the reaction order.

关 键 词：动力学 内扩散 活化能 稀土 风化壳 

分 类 号：TF845[冶金工程—有色金属冶金]