微细粒铜镍硫化矿表面氧化机制与浮选电化学动力学

Copper-nickel ore in Sichuan Danba area has low-grade Ni, fine-grain dissemination and high-content Mg, the enrichment and recovery of nickel minerals has received much attention of mining industry, because nickel is mainly occurred in pentlandite and nickel ppyrrhotite and these minerals are easily oxidation and has similar flotability.Taking refractory superfine copper-nickel ore of Danba area in Sichuan as study object, by adopting electrochemistry to explore the oxidized products composition on copper-nickel sulfide ore surface in the presence of inevitable ions and under other different conditions such as pulp potential, pH value and collector concentration, and analyse the effect of the aboved on flotability of superfine copper-nickel ore to achievie quantification of mineral surface, and discuss the micromechanism of the difference between surface oxidized products and flotability. The study will aslo establish the flotation electrochemisty kinetics equation of superfine copper-nickel surfide ore, work out kinetics parameters of the electrode oxidation, prove itself oxidation speed difference under different conditions and the relationship beteen its floatability, and reveal the microscopic difference of oxidation speed and flotation behaviors. Those studies will be expected to perfect the theoretical foundation for flotation separation of superfine copper-nickel sulfide ore.

镍品位低和嵌布粒度细及含镁高的四川丹巴地区的铜镍矿，因镍主要以镍黄铁矿和镍磁黄铁矿赋存，它们与黄铁矿可浮性相近且易氧化，镍矿难以分选富集，一直受到矿业界的极大重视。本研究以四川丹巴地区难选微细粒铜镍矿为研究对象，采用电化学研究手段，探索在难免离子存在，不同的矿浆电位Eh和pH及捕收剂浓度等条件下，微细粒铜镍硫化矿表面氧化产物组成，分析其对微细粒铜镍硫化矿可浮性的影响，实现矿物表面状态量化描述，探讨表面氧化产物与可浮性差异的微观机制，建立微细粒铜镍硫化矿浮选电化学动力学方程，计算出其电极氧化的动力学参数，阐明不同条件下电极自身氧化速度的差异及与其可浮性的关系，揭示其氧化速率与浮选行为的微观差异，为微细粒铜镍硫化矿高效浮选分离奠定理论基础。

微细粒铜镍硫化矿的浮选分离与回收一直是国内外选矿界研究的重点与难点。本项目以几种典型复杂难选铜镍多金属硫化矿石为研究对象，利用电化学原理与实验方法，系统的考察了镍黄铁矿和黄铜矿在自诱导和捕收剂诱导条件下的浮选行为；利用电化学测试方法中的循环伏安法研究了水体系和捕收剂体系下硫化铜镍矿的表面氧化产物；采用循环伏安曲线、Tafel 曲线、恒电位阶跃等电化学测试手段，结合热力学计算和分析，探索了pH值，捕收剂等因素对镍黄铁矿、黄铜矿表面氧化过程及表面氧化产物组成的影响，得出了黄铜矿与镍黄铁矿硫化矿表面氧化的动力学参数和方程；通过紫外和红外测试技术研究了丁基黄药作为捕收剂时，硫化铜镍矿表面生成的疏水产物和吸附量，揭示了微细粒铜镍硫化矿表面氧化机制与浮选电化学动力学；基于铜镍浮选电化学理论研究成果，设计了复杂难选铜镍硫化矿清洁选矿新工艺，并进行了小型试验，在小型试验的基础上成功地把新工艺应用于生产实践，取得了较好的选别指标。本项目探索的理论与开发的选矿新工艺，可为复杂难选铜镍多金属硫化矿石的浮选回收提供理论支持与技术思路。