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在酸性矿山废水中,氧化亚铁硫杆菌(A.ferrooxidans)氧化Fe~(2+)过程中常常伴随着次生矿物的生成.为研究温度和pH对A.ferrooxidans氧化Fe~(2+)及Fe3+水解成矿的综合影响,考察了初始pH为1.5、2.0、2.5、3.0,温度为8、18、28、38℃时体系中Fe~(2+)、总Fe、次生矿物的变化情况.结果表明,在改良9K培养基中,温度和pH均影响Fe~(2+)生物氧化和Fe~(3+)水解成矿.A.ferrooxidans最佳适宜生长环境为温度28℃,pH=2.0~3.0,其它条件均不利于其生长繁殖,导致Fe~(2+)氧化速度明显变慢.起始pH=1.5时,不同温度处理均未发现有矿物生成,pH越高,收集矿物量越多.次生铁矿物XRD图谱表明,反应温度为28℃时,pH=2.0~2.5条件下次生铁矿物主要为黄铁矾和施氏矿物的混合物,而pH=3.0时则更有利于施氏矿物的形成.该现象对有效调控次生矿物的形成具有潜在意义.
In acidic mine wastewater, secondary ferrous minerals are often accompanied by the oxidation of Fe 2+ by A.ferrooxidans.In order to study the effect of temperature and pH on the oxidation of Fe 2+ by A. ferrooxidans, And Fe3 + mineralization, the changes of Fe2 +, total Fe and secondary minerals in the system with initial pH of 1.5, 2.0, 2.5 and 3.0 at 8, 18, 28 and 38 ℃ were investigated. .The results showed that the temperature and pH all affected the Fe 2+ bioxidation and Fe 3+ mineralization in the modified 9K medium.The best suitable growth environment for A.ferrooxidans was temperature 28 ℃, = 2.0 ~ 3.0, other conditions are not conducive to its growth and reproduction, resulting in the oxidation rate of Fe ~ (2 +) significantly slowed down.When the initial pH = 1.5, no mineral was found in different temperature treatments, the higher the pH, The more the amount of iron ore, the XRD patterns of secondary iron minerals showed that the secondary iron minerals were mainly mixture of jarosite and Shih-Shi mineral at pH = 2.0 ~ 2.5 at 28 ℃, The formation of minerals.This phenomenon has potential significance for the effective regulation of the formation of secondary minerals.