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研究了２５℃下，不同ｐＨ时磷酸盐（ＫＨ２ＰＯ４）对黄铁矿（ＦｅＳ２）氧化的影响。流动态中，黄铁矿氧化服从假零级反应规律。经０．１ｍｏｌ／ＬＨ２Ｏ２＋０．０１ｍｏｌ／ＬＫＨ２ＰＯ４混合液（ｐＨ分别为３，５和７）淋洗４８０ｍｉｎ后，再经相应ｐＨ的０．１ｍｏｌ／ＬＨ２Ｏ２溶液淋洗４００ｍｉｎ，黄铁矿剩余百分率分别从对照的９４．９２％，９７．５２％和９９．３８％提高到９８．１５％，９９．５２％和９９．４８％，分别增加了３．２３％，２．００％和０．１０％。ｐＨ５和ｐＨ７时的对照和处理样品，换用ｐＨ３的０．１ｍｏｌ／ＬＨ２Ｏ２淋洗４００ｍｉｎ后，则对照组的剩余百分率分别为９６．１７％和９８．１６％，下降了１．３５％和１．２２％。而经磷酸盐处理的变化较小，分别为９９．３２％和９８．９５％，仅下降了０．２０％和０．５３％。随溶液ｐＨ提高，黄铁矿氧化速度下降，这与ｐＨ升高，导致Ｈ２Ｏ２氧化能力下降有关。ｐＨ７时，ＯＨ－和Ｆｅ３＋反应强烈，生成Ｆｅ（ＯＨ）３被吸附沉积在黄铁矿表面，抑制黄铁矿氧化，但Ｆｅ（ＯＨ）３膜不够稳定，对Ｈ＋浓度较敏感。
The effects of phosphate (KH2PO4) on the oxidation of pyrite (FeS2) at 25 ℃ were investigated. In the fluid state, the pyrite oxidizes obey the rules of fake zero-order reaction. After the rinsing with 0.1 mol / L H2O2 + 0.01 mol / L KH2PO4 (pH 3, 5 and 7 respectively) for 480 min and then with the corresponding pH 0.1 mol / LH2O2 solution for 400 min, the remaining percentage of pyrite was 94.92%, 97.52% and 99.38% increased to 98.15%, 99.52% and 99.48%, increased by 3.23%, 2.00% and 0.10% respectively. Control and treatment samples at pH 5 and pH 7, after switching to pH 3 0.1 mol / LH 2 O 2 for 400 min, the remaining percentage of the control group was 96.17% and 98.16% respectively, down 1.35% and 1 .22%. However, the change of phosphate treatment was smaller, which was 99.32% and 98.95% respectively, only decreased by 0.20% and 0.53% respectively. With the increase of solution pH, the rate of pyrite oxidation decreased, which was related to the increase of pH and the decrease of oxidative capacity of H2O2. At pH7, Fe (OH) 3 was adsorbed and deposited on the surface of pyrite, which inhibited the oxidation of pyrite, but the Fe (OH) 3 film was not stable enough and sensitive to H + concentration.