细粒辉钼矿表面的过度氧化以及表面氧化产物的溶解行为不利于辉钼矿浮选，为此，研究采用硫酸钠减小细粒辉钼矿表面氧化的程度以及抑制表面氧化产物的溶解以期改善辉钼矿的浮选效果。结果表明，适量的硫酸钠可减小细粒辉钼矿表面Mo−O键的相对含量，对细粒辉钼矿氧化反应及氧化产物的溶解过程具有一定的调控作用。0.08 mol/L的硫酸钠可使矿浆中矿物溶解的硫酸根离子质量浓度减小68.25%，溶解氧质量浓度减小25.81%，并使细粒辉钼矿（100）晶面的晶面间距减小，而结晶度增大。其次，硫酸钠在溶液中电离出的硫酸根离子对辉钼矿表面硫元素氧化产物的溶解反应产生同离子效应，使氧化产物溶解受阻，提高了细粒辉钼矿表面性质的均匀性和可浮性。研究对细粒辉钼矿氧化−溶解过程的调控及其浮选效果的提高具有一定的指导意义。

The excessive oxidation on the surface of micro−fine molybdenite and the dissolution behavior of the surface oxidation products are not favorable for molybdenite flotation, for this reason, sodium sulfate was used to reduce the degree of surface oxidation of fine−grained molybdenite and inhibit the dissolution of surface oxidation products in order to improve the flotation efficiency of molybdenite. The results indicated that the appropriate amount of sodium sulfate could reduce relative content of Mo−O bonds on the surface of micro−fine molybdenite, which had a certain regulatory effect on the oxidation reaction of micro−fine molybdenite and the dissolution process of oxidation products. Sodium sulfate at 0.08 mol/L reduced the sulfate ion concentration in the slurry by 68.25% and the dissolved oxygen concentration by 25.81%, and reduced the crystalline spacing of the micro−fine molybdenite (100) crystal faces, while increasing the crystallinity. Secondly, the sulfate ions ionized by sodium sulfate in solution produce a common ion effect on the dissolution reaction of sulfur oxidation products on the surface of molybdenite, which hindered the dissolution of oxidation products and improved the uniformity and floatability of fine−grained molybdenite surface properties. The study has certain guiding significance for the regulation of the oxidation−dissolution process of micro−fine molybdenite and its flotation effects improvement.