盐湖铝系提锂吸附剂成型条件的影响研究  

Study on the influence of granulation conditions on Li/Al-LDHs for lithium recovery from low grade brine

作　　者：张瑞[1,2] 钟静 林森[1,2] 于建国[1,2] ZHANG Rui;ZHONG Jing;LIN Sen;YU Jianguo(National Engineering Research Center for Integrated Utilization of Salt Lake Resources,East China University of Science and Technology,Shanghai 200237,China;Engineering Research Center of Salt Lake Resources Process Engineering,Ministry of Education,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学国家盐湖资源综合利用工程技术研究中心,上海200237 [2]华东理工大学资源过程工程教育部工程研究中心,上海200237

出　　处：《化工学报》2021年第12期6291-6297,共7页CIESC Journal

基　　金：国家重点研发计划项目(2018YFC0604805);国家自然科学基金项目(U20A20142,21978094)。

摘　　要：铝系锂吸附剂成型颗粒在盐湖卤水提锂工业应用过程中存在吸附容量低、吸附速率慢和吸附剂粉末脱落等问题。基于现有反溶剂法挤压成型工艺,对盐湖铝系提锂吸附剂成型条件的影响进行了系统性研究。实验结果显示吸附剂成型颗粒粒径越小,达到吸附平衡越快,当颗粒直径d<1 mm时,吸附剂颗粒可在24 h左右达到吸附平衡;降低黏结剂浓度可有效加快吸附剂颗粒的吸附速率,但黏结剂浓度过低会导致其对粉末的包裹性下降;吸附剂颗粒的吸附速率与致孔剂添加比例成正比,当致孔剂添加比例为20%时,吸附剂颗粒能在4 h内完成快速吸附阶段,吸附平衡时对察尔汗高镁锂比盐湖卤水中锂的吸附容量可达4.97 mg·g^(-1)。The aluminum-based adsorbent is an effective adsorbent for lithium recovery from brines with an ultrahigh Mg/Li ratio. And the granulated Li/Al-LDHs adsorbent has been widely used in the salt lake lithium extraction industry, but low adsorption capacity, slow adsorption rate and powder loss are the common problems in industrial. In this work, the anti-solvent method is used to granulate the Li/Al-LDHs adsorbent powder with high hydrophilicity and the effects of granulating conditions are also investigated comprehensively. The experimental results show that, the smaller the diameter of the adsorbent particles, the faster the adsorption equilibrium is reached. When particle diameter <1 mm, the adsorbent can reach adsorption equilibrium in about 24 h. Diluting the binder concentration can effectively accelerate the adsorption rate of the adsorbent, but would increase the powder loss in the adsorbent particles. Adding NaCl as a porogen can shorten the time for the adsorbent reaching equilibrium, specially, the adsorbent particles can accomplish the rapid adsorption in about 4 h and the lithium adsorption capacity at equilibrium can reach 4.97 mg·g^(-1) with 20% of the NaCl addition ratio in the Qarham old brine with a high Mg^(2+)/Li^(+) ratio.

关 键 词：盐湖卤水 铝系吸附剂 锂吸附 成型造粒 

分 类 号：TQ133.1[化学工程—无机化工] TQ131.1