酸浸脱除精矿中蛇纹石降镁过程的热力学分析

应用热力学原理计算并分析精矿中蛇纹石、各种铁矿物及硫化铜矿物与稀酸反应的活性。结果表明,蛇纹石极易与稀酸反应,其中MgO可完全溶于稀酸中,铁矿物中的FeO、FeCO3、FeO·SiO2也较易与稀酸反应,FeS(磁黄铁矿)亦与稀酸有一定的反应,而Fe2O3、FeS2(黄铁矿)则不会与稀酸反应,硫化铜矿物也不易与稀酸反应。因此,以蛇纹石为主要含镁脉石的铜、镍硫化矿或贵金属矿,仅通过浮选难以获得低镁精矿时,可以用稀酸浸出的办法降低其最终精矿中的MgO含量。

Thermodynamically Analysis on Diluted Acid Leaching Process of Serpentine

The reactive activities of serpentine, various minerals Fe containing and copper-nickel sulfide minerals in concentrate with diluted sulfuric acid are thermodynamically calculated and analyzed. The results show that serpentine can easily react with diluted sulfuric acid and the MgO in it can be dissolved completely. Carbonate and silicate of iron as well as FeO in the minerals may also react with diluted sulfuric acid. Pyrrhotite (FeS) can react with diluted sulfuric acid in some extent, but pyrite (FeS_2) and iron oxide (Fe_2O_3) can not be dissolved in diluted sulfuric acid. Chalcopyrite and pentlandite are not reacted with diluted sulfuric acid. Therefore, if the main gangue in nickel-copper or precious metals concentrate is serpentine and it is difficult to be removed only by floatation, the MgO content in final concentrate could be reduced by leaching with diluted sulfuric acid.