稀土尾矿水热直接合成A型分子筛  

Direct Synthesis of A-Type Molecular Sieve from Rare Earth Tailings by Hydrothermal Method

作　　者：侯丽敏 许杰 何洋 栗浩博 武文斐 HOU Li-min;XU Jie;HE Yang;LI Hao-bo;WU Wen-fei(Key Laboratory of Efficient and Clean Combustion in Inner Mongolia Autonomous Region,School of Energy and Environment,Inner Mongolia University of Science&Technology,Baotou 014010,China;Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources,Inner Mongolia University of Science&Technology,Baotou 014010,China;Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources,Inner Mongolia University of Science and Technology,Baotou 014010,China)

机构地区：[1]内蒙古科技大学能源与环境学院,内蒙古自治区高效洁净燃烧重点实验室,内蒙古包头014010 [2]内蒙古科技大学,白云鄂博矿多金属资源综合利用重点实验室,内蒙古包头014010 [3]内蒙古科技大学,白云鄂博共伴生矿资源高效综合利用省部共建协同创新中心,内蒙古包头014010

出　　处：《稀有金属与硬质合金》2023年第4期57-64,共8页Rare Metals and Cemented Carbides

基　　金：国家重点研发计划项目(2020YFC1909102);内蒙古自然科学基金项目(2019ZD13,2020BS05030);国家自然科学基金项目(51866013);内蒙古自治区本级事业单位引进人才科研启动支持经费。

摘　　要：以白云鄂博稀土尾矿为原材料,碱熔活化稀土尾矿为硅源,偏铝酸钠为铝源,直接水热合成A型分子筛,以实现稀土尾矿资源二次利用。研究碱的添加量对稀土尾矿硅活化和偏铝酸钠添加量对分子筛合成的影响,采用XRF、XRD、SEM-EDS、BET等手段对合成分子筛的物相组成、微观形貌和孔结构进行分析。结果表明,当碱矿质量比为3时,尾矿活化较为完全,结晶态硅物种转变为可溶性的活性Si元素,Si元素的溶出率为84%。在无模板剂的条件下,碱熔活化稀土尾矿在不同硅铝物质的量之比下均能合成A型分子筛,分子筛呈规则的球形结构,具有较大的比表面积和孔容,孔结构为微孔,SiO_(2)/Al_(2)O_(3)物质的量之比为1.5时合成的A型分子筛比表面积最大,为215.5 m^(2)/g。尾矿中的Fe、Mg和Si元素与Al元素反应生成铁铝直闪石杂质,降低了A型分子筛结晶度。Taking the Bayan Obo rare earth tailings as raw materials,alkali melt-activated rare earth tailings as silicon source and sodium metaaluminate as aluminum source,A-type molecular sieve was direct synthetized by hydrothermal method to realize the secondary utilization of rare earth tailings.The effects of the amount of alkali addition on the silicon activation of rare earth tailings and the amount of sodium metaaluminate addition on the synthesis of the molecular sieve were studied,and the phase composition,micro-morphology,and pore structure of the synthesized molecular sieve were analyzed by XRF,XRD,SEM-EDS,and BET.The results show that when the alkali-ore mass ratio is 3,the tailings are fully activated and the crystalline silicon species are transformed into soluble active Si element,of which the dissolution rate is 84%.Under the template-free condition,the A-type molecular sieve can be synthesized from alkali melt-activated rare earth tailings with different SiO_(2)/Al_2O_(3) molar ratios,presenting a regular spherical structure with large specific surface area and pore volume,with the pore structure in microporous form.When SiO_(2)/Al_(2)O_(3) molar ratios is 1.5,the synthesized A-type molecular sieve has the maximum specific surface area of 215.5 m^(2)/g.Fe,Mg and Si in the tailings react with Al to form ferric aluminum anthophyllite impurities,which reduce the crystallinity of the A-type molecular sieve.

关 键 词：稀土尾矿 碱熔活化 水热法 分子筛 资源 

分 类 号：TD983[矿业工程—选矿]