含铁硅酸盐矿物的表面特性及抑制与活化机理研究

According to the fact of property convergence or similarity of iron bearing silicates and ferric oxidess, and it is very difficult to separate them efficiently. The subject takes nature ores and pure minerals such as iron bearing silicate and ferric oxides as the research object, and the combinations of quantum chemistry, solution chemistry and experimental research as research methods. The influence law of quantum chemistry parameters on surface property, surface absorption and response characteristic, and reagents structure and reagents performance and their relationships will be further studied, which reveal the surface characteristics and the selectivity depression and activation mechanism of iron bearing silicates, and then the flotability difference between iron bearing silicates and ferric oxides is enlarged by regulation in anionic reverse flotation system. So the highly efficient separation of iron bearing silicates and ferric oxides comes true. The results can not only reveal the inner link (interface features) and nature law between microstructure and macro properties of silicate minerals and enrich the regulation theory of selective inhibition and activation, also help to formulate the high efficiency separation process of iron bearing silicates and ferric oxides by anionic reverse flotation, and play an important role in theoretical significance and practical value.

含铁硅酸盐矿物和氧化铁矿物因性质趋同或相似，难以实现高效分离。为此，本课题拟以含铁硅酸盐和氧化铁单矿物以及实际矿石为研究对象，以量子化学、溶液化学分析与实验研究相结合的研究方法，深入研究量子化学参数对矿物表面性质、表面吸附和反应特性的影响规律，以及浮选剂结构、性能及其结构与性能之间的关系，揭示含铁硅酸盐矿物和氧化铁矿物的矿物表面特性及选择性抑制与活化机理，进而通过调控机制增大阴离子反浮选体系中含铁硅酸盐矿物与氧化铁矿物浮游性的差异，实现含铁硅酸盐矿物和氧化铁矿物的高效分离。该研究成果不仅能揭示硅酸盐矿物的微观结构与宏观性能（表界面特性）之间的内在联系和本质规律，丰富选择性抑制和活化调控理论，并有助于制定含铁硅酸盐矿物和氧化铁矿物阴离子反浮选高效分选新工艺，具有重要的理论意义和实际价值。

绿泥石和霓石等含铁硅酸矿矿物易泥化、粒度细、极易水化等特性给其分选带来了极大困难，而颗粒界面性质及调控是核心问题。课题以含铁硅酸盐和氧化铁单矿物以及实际矿石为研究对象，以固液界面物理化学作用理论为基础，借助理论与实验相结合的研究方法，通过理论及现代分析技术探索矿物水溶液化学环境与微细含铁硅酸盐矿物颗粒界面物化作用机制，构建微细粒含铁硅酸盐矿物与浮选剂吸附模型，掌握了微细粒含铁硅酸盐矿物颗粒界面调控规律，经调控增大反浮选体系中含铁硅酸盐矿物与氧化铁矿物浮游性的差异，实现含铁硅酸盐矿物和氧化铁矿物的有效分离。.研究结果表明：镜铁矿溶出的离子主要为Fe3+，绿泥石溶出的离子主要为Fe3+、Mg2+和Al3+，霓石溶出的离子主要为Fe3+和Na+，溶出金属离子量绿泥石＞霓石＞镜铁矿；三价离子（Fe3+和Al3+）在矿物表面的吸附量大于二价离子（Ca2+和Mg2+）；Al3+在矿物表面吸附量：镜铁矿＞霓石＞绿泥石；Fe3+在矿物表面吸附量：镜铁矿＞绿泥石＞霓石；Ca2+和Mg2+在三种矿物表面吸附量相差不大。Al3+和Fe3+完全抑制三种矿物浮选；Fe2+完全抑制绿泥石和霓石，对镜铁矿抑制较弱；Ca2+和Mg2+对三种矿物的抑制效果较弱；Na+对三种矿物的可浮性无明显影响。.金属离子及其羟基络合物通过静电吸附在矿物表面，提高矿物表面电位，减弱浮选剂有效组分与矿物的静电吸附；亲水性的氢氧化物吸附于矿物表面，降低矿物表面疏水性；两性氢氧化物在碱性条件下溶解生成带负电荷的羟基络合物与浮选剂的有效组分反应，消耗矿浆中捕收剂，抑制了矿物的浮选。课题提出的双絮凝技术原型为微细粒矿物的分选提供依据，含铁硅酸盐矿物颗粒界面吸附活性点位、水分子、离子及不同药剂吸附研究成果为微细含铁硅酸盐矿物颗粒界面调控药剂优化选择及药剂设计提供理论支持。