柱子淋洗模拟研究磷酸铁膜抑制黄铁矿氧化效果

自然室温条件下用柱子淋洗模拟研究了接氧化亚铁硫杆菌（Ｔｈｉｏｂａｃｉｌｌｕｓ ｆｅｒｒｏｏｘｉｄａｎｓ，简称Ｔ．Ｆ菌）时磷酸铁膜抑制黄铁矿氧化的效果。试验结果首次指出：用ＫＨ２ＰＯ４与Ｈ２Ｏ２淋洗黄铁矿，在其表面形成的磷酸铁膜不能抑制黄铁矿的生物氧化，反而在一定程度上加速其氧化进程。经包膜后的黄铁矿矿石柱子间歇循环淋洗一年后的收集液中ＳＯ４＾２－累积量高达３３７５６．１ｍｇ；为对照组的１．６倍，是

Effect of iron phosphate coating on control of pyrite oxidation using simulation of column leaching

The effect of iron phosphate coating on control of pyrite oxidation at room temperatures was studied using simulation of column leaching. The results for the first time indicated that the iron phosphate coating on pyrite surfaces could not suppress pyrite oxidation caused by Thiobacillus ferrooxidan but accelerated its oxidation rate to a certain extent. The amount of in the leachate reached to 33 756.1 mg when the column of pyrite coated with iron phosphate was leached at intervals and circularly with distilled water for one year. The rate of sulfate released was 1.6 times as much as that of control and 54 times as much as that of bactericide. pH in the leachate dropped from 7.4 at the beginning to 2.3 after one year . The color of the leachate looked dark red brown. The contents of other elements in the leachate were almost equal to those in the control, but were much higher than those in the bactericide. When the mineral samples leached for one year were observed with scanning electron microscope, the surfaces of pyrite for the control and for the FePO4 coating were dotted and appeared smoothly for the bactericide. This clearly showed that Thiobacillus ferrooxidans played a very important role in pyrite oxidation.