盐湖锂资源直接提取及精制加工技术

Study on Key Materials and Technology for Lithium Recovery from Salt Lake

我国盐湖锂资源丰富,但开发的理论基础和技术关键均没有实质性突破,高镁锂比卤水中锂的直接提取技术的突破是我国盐湖锂资源开发的急迫需求。该课题以国家战略需求为导向,着眼于解决国际上高Mg/Li比盐湖卤水提锂的关键技术问题,符合国家中长期科技发展纲要的要求。通过该课题研究,将提高盐湖锂资源提取技术集成创新能力,实现盐湖资源平衡综合开发和利用,促进盐湖地区资源优势转化为经济优势,构建盐湖卤水综合利用的新型产业链。主要研究内容包括：（1）分离用锂离子筛功能材料设计与制备：设计制备对Li^＋具有特殊选择性和高交换容量的离子筛型吸附剂,研究Mg/Li比与其他共存离子对提锂性能的影响,揭示离子筛氧化物结构与其反应分离性能之间的内在规律。（2）盐湖锂离子快速识别络合吸附材料合成及制备：采用传感信号响应技术,设计并快速筛选高选择性锂离子受体,创制新型络合吸附分离材料,探讨材料构性等对锂离子的分离性能,提出最优化的分离材料设计方案,研究络合吸附材料微观结构与锂离子吸附性能的关系。（3）盐湖高锂选择性复合吸附材料合成与优化：发展以分子模拟技术为指导、高锂选择性为导向的新型复合吸附材料设计方法,实现以氢氧化物为改性吸附剂的可控合成,确定合成工艺中优化的改性吸附剂浓度,并优化合成工艺参数。（4）吸附功能材料规模化制备关键技术：冷模研究规模化制备吸附材料合成釜中流体流动特性,结合CFD确定合成釜放大关键参数和放大准则;研究成型工艺,考察在吸附-脱附过程中的稳定性;批量制备吸附剂。（5）卤水直接提锂工艺及示范装置：确定吸附-脱附最佳工艺流程和参数;建立提锂过程模型,通过模拟和分析确定最优工艺参数;开发新型LiCl分离技术工艺软件包;建设100 t/a氯化锂提取装置,并进行示范运行。（6）Li2CO3精制加工关键技术研究：针对不同的卤水组成,开发相应的除杂富锂关键技术,获得初级碳酸锂产品,并进一步精制加工,最终形成适应我国盐湖资源特点的高纯碳酸锂和电池级碳酸锂产品制备成套技术。预期目标：（1）建立100 t级LiCl提锂示范装置。锂的收率≥85%,LiCl纯度≥99%;（2）申请相关发明专利8-10项;发表高水平论文10-15篇;（3）培养博士研究生8-10名,硕士研究生12-15名,形成1个专门从事盐湖资源开发利用的创新团队。

China is abundant in saline lithium resource, but the basic theory and key technique for the recovery of lithium from salt lake are short of substantive breakthroughs. To develop salt lake lithium resources, direct lithium extraction technique from high Mg/Li ratio brine is urgently needed. The project fulfills the outline of the national program for longand-medium term scientific and technological development. The main research contents in detail are following：（1） Design andprepare the lithium separation materials Ion-sieve adsorbents with a high selectivity and adsorption capacity for Li^＋ are designed and prepared. The effect of Mg/Li ratio and other co-existing ions on lithium extracting performance is discussed.The correlation of the structure and the separation performance of these nano ion-sieve systems are investigate.（2） Synthesis quickly Li^＋-identifying and chelating adsorbent materials The sensing signal response technology is utilized to design and select Li^＋. The effect of structural characteristic on Li^＋ separation ability is investigated. An optimization design of separation materials is proposed.（3） Synthesis and optimize composite Li＋ adsorption materials A molecular modeling technology is developed to design for composite Li＋ adsorption material. The concentration of the modified adsorbent, and optimize the process parameters are determined.（4） The key technology for large-scale preparation of adsorbent functional materials The fluid characteristics in the reactor is investigated during the synthesize process by cold model unit and CFD. Investigate the shaping process and stability during the adsorption and desorption process.（5） Develop a process for direct lithium extraction technique from brine and build a demonstration facility The optimized adsorption-desorption process and parameters are determined. A new LiCl separation technology process is developed. A device with a 100 t annual output and demonstration running is built.（6） Study the key technique of Li2CO3 refinement The key technology of impurity removal and lithium enrich for various brine composition is developed. A Li2CO3 refinement technology is developed to form a packaged technology of high-purity and battery grade Li2CO3 preparation.