非传统难选钨矿浮选分离的晶体及界面物理化学基础研究

Tungsten rare metal is an important strategic metal, and unconventional refractory mineral resources are its main sources. However, this type of mineral resources is unrecoverable with the current technology, due to its complex mineral composition and extremely fine dissemination size. At present, rare fundamental research about its utilization has been reported. In this work, taking unconventional refractory tungsten ores (mainly containing scheelite, wolframite, fluorite, calcite) as research objects, the following research contents will be included. The relationship between mineral crystal structure and its surface physico-chemical properties, such as its growth habit, cleavage nature, wettability, surface free energy, will be investigated and built. The effect of the differences in mineral crystal structures on the selective interaction between flotation reagents and commonly exposed mineral surfaces will be systematically investigated, and accordingly the more effective and selective flotation reagents will be selected and/or designed. The impact of interfacial polar interaction between mineral surfaces, and changes in pulp phycico-chemical conditions on the aggregation or dispersion behaviors of fine mineral particles will be studied, and hereby the controlling mechanism and method based on interfacial physico-chemistry aiming at the selective aggregation or dispersion of fine mineral particles will be developed. All the above research results will lead to the formation of a new theory on the flotation separation of unconventional refractory tungsten ores based on crystal and interfacial physico-chemistry. The research results in this project will be meaningful to select and/or design more effective and selective flotation reagents for tungsten minerals flotation, to effectively guide the flotation separation practice of unconventional refractory tungsten minerals, and to promote the utilization ratio of this type of mineral resources.

钨是重要的战略金属，非传统难选钨矿物资源是其重要来源。而该类型矿物资源组成复杂、嵌布粒度细、泥化严重、目前难以经济利用，基础研究薄弱。本项目以非传统难选钨矿的主要组成矿物（白钨矿、黑钨矿、萤石、方解石）为对象，研究矿物晶体结构与矿物结晶、解理性质及常见暴露面润湿性、表面自由能等晶体及表面物理化学性质的关系；研究常见暴露面结构性质差异对浮选剂/矿物选择性作用的影响，并对浮选剂进行筛选优化，建立钨矿高效浮选剂结构-性能的定量判据；研究细颗粒界面极性相互作用力、矿浆溶液物理化学条件变化对细粒钨矿选择性聚集与分散行为的影响，建立微细粒钨矿选择性聚集与分散强化浮选的界面物理化学调控机制。系统研究成果形成非传统难选钨矿浮选分离的晶体及界面物理化学理论。本研究对于促进钨矿高效浮选剂的筛选及优化设计，更普遍地指导非传统难选钨矿的浮选回收实践，提高该类型矿物资源的综合利用率，具有重要的理论意义和实际价值。

钨是重要的战略金属，非传统风化白钨矿资源是其最重要来源。但是，该资源特点是白钨矿组分含量低，与方解石和萤石等紧密共生，嵌布粒度细，分离难度大。浮选是分离此类型矿物资源最主要的方法。浮选过程中，捕收剂的选择性决定不同矿物的分离效果。由于白钨矿（目的矿物）与方解石和萤石（非目的矿物）表面性质很相似，传统的羧酸类捕收剂很难体现出作用的选择性，亟需设计高选择性的捕收剂。本项目基于三种含钙矿物的晶体(表面)结构，研究并总结表面断裂键性质、解理及暴露面性质、表面(自由)能、润湿性、表面电性、吸附性等表面物理化学性质的各向异性，建立了三种含钙矿物晶体结构特征与表面性质之间的关系，以及不同表面性质之间的关联。发现，表面断裂键密度和表面能存在正相关性，表面断裂键密度可准确预测萤石的解理和暴露面性质，表面离子层结构差异、表面Ca质点及其断裂键差异可解释表面电性、润湿性、溶解性及吸附性的各向异性。基于三种含钙矿物表面Ca质点的差异，本项目研究合成了一种羟肟酸类复合捕收剂，兼具良好的捕收性能和作用选择性，通过实验室小试，扩大中试以及现场工业试验，能显著提高白钨矿与萤石和方解石的分离效率，显著提高白钨矿的浮选回收率，为非传统风化钨矿的高效综合利用提供了技术支撑。