含钙矿物常见暴露面各向异性与浮选分离高效捕收剂设计

Scheelite and fluorite, as two valuable calcic minerals, are the main sources for tungsten metal and fluorine nonmetal, respectively. However, scheelite and fluorite coexist with another calcic gangue mineral calcite in ore deposit. Due to the same Ca active sites and similar surface properties they have, the flotation separation from each other is always a thorny problem in the mineral processing field. Designing new collectors with higher selectivity is a top priority for the successful separation. However, the conventional molecular design method has limitations, and a novel design method should be explored. Latest literature reported that the structures and properties of commonly exposed surfaces of different minerals with the same active sites, exhibit some differences which obviously affect the selective adsorption of collector on those minerals. These findings provided some useful evidence for solving the above problem. In this project, we will firstly investigate anisotropic commonly exposed surfaces of scheelite, fluorite and calcite (e.g., surface structure, Ca spatial distribution and coordination at the toplayer), based on which, the functional group and hydrocarbon tail structures will be designed using advanced molecular modeling software, and the collecting ability and selectivity of tailored collectors will be evaluated using interaction energy and selectivity index reported in previous literature. Consequently, a novel collector design method for the separation of calcic minerals will be established. Then the green collectors with both higher collecting power and selectivity will be environmentally synthesized, tried from lab scale to pilot scale and finally applied in flotation plants, which ultimately help improve the utilization of scheelite and fluorite resources.

有价含钙矿物白钨矿和萤石分别是金属钨和非金属氟的最主要来源。但在矿床中，它们常与含钙脉石矿物方解石紧密共生，三种矿物表面活性质点相同、性质相近，常规捕收剂浮选选择性差，导致含钙矿物分离是矿物加工领域世界性难题。针对含钙矿物分离，传统的捕收剂设计方法具有局限性，亟需探索新的设计思路与方法。前期研究表明，表面性质相似的不同矿物的常见暴露面的结构和性质存在差异，影响浮选剂在不同矿物表面的选择性吸附行为，为解决上述问题提供了新的思路。本项目重点研究三种含钙矿物常见暴露面的各向异性，并基于三种矿物常见暴露面结构与暴露面上Ca活性质点的空间分布与价键特性差异，借助先进的分子模拟软件设计捕收剂分子活性基团和疏水结构，并利用相互作用能和选择性指数综合评价所设计捕收剂的捕收能力和选择性，形成含钙矿物浮选捕收剂设计新方法，据此制备出2-3种绿色环保的高效捕收剂，并实现工业应用，提高白钨矿和萤石的综合利用水平。

稀缺性战略含钙矿物白钨矿和萤石是钨和氟的重要来源，但它们常与脉石矿物方解石紧密共生。这三种含钙矿物表面活性质点相同（Ca）、性质相近，常规捕收剂浮选选择性差，导致含钙矿物分离成为矿物加工领域的世界性难题。针对含钙矿物分离，传统的捕收剂设计方法具有局限性，亟需探索新的设计思路与方法。本项目从含钙矿物表面各向异性研究、新型含钙矿物选择性捕收剂的设计、合成与应用和含钙矿物浮选新药剂的筛选及应用等三个方面开展研究。基于表面断裂键理论创建了解析含钙矿物表面各向异性的新体系，提出了调控矿物晶面暴露程度强化含钙矿物浮选的新思想，借助AFM 探针创建了直接检测含钙矿物表面各向异性的新方法。基于含钙矿物电性差异，自主组装并研发出新型Pb-BHA-NaOL金属有机三元配位体捕收剂，实现白钨矿和萤石选择性分离；基于含钙矿物表面阴离子基团氢键键合能力的差异，自主设计并合成了氢键-配位双功能基捕收剂，实现三种典型含钙矿物的选择性分离。此外，筛选出BHA/NaOL复合捕收剂、发泡剂月桂酰肌氨酸钠、阻垢剂HEDP等新型浮选药剂，优化现有药剂制度，实现了白钨矿与方解石和萤石的选择性分离。本项目研究结果为含钙矿物高效分离浮选药剂的开发提供了新思路，为白钨矿和萤石的高效利用提供了技术支撑。项目执行期间，共发表SCI论文21篇，EI论文1篇。共申请中国发明专利17项，其中已授权14项。负责人高志勇受邀担任学科排名最权威期刊Minerals Engineering的编委和JCR二区期刊Minerals的副主编，入选国家“万人计划”科技创新领军人才、教育部青年长江学者，获MEI青年科学家奖（亚洲首位）和湖南省杰出青年科学基金。