三种次生矿物固定A.ferrooxidans的Fe^2+氧化及成矿性能比较  

Fe^2+oxidation and mineralization properties of Acidithiobacillus ferrooxidans immobilized on three secondary iron minerals

作　　者：宋永伟[1] 王蕊[1] 杨琳琳 王鹤茹 杨俊[1] 曹艳晓[1] SONG Yong-wei;WANG Rui;YANG Lin-lin;WANG He-ru;YANG Jun;CAO Yan-xiao(Department of Environmental Science and Engineering,Zhongnan University of Economics and Law,Wuhan 430073,China)

机构地区：[1]中南财经政法大学环境科学与工程系,湖北武汉430073

出　　处：《中国环境科学》2020年第5期2073-2080,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(21906183);湖北省软科学基金资助项目(2019ADC152);中南财经政法大学中央高校基本科研业务费专项资金资助项目(2722020JCG068,2722020PY061)。

摘　　要：氧化亚铁硫杆菌(A.ferrooxidans)介导的生物矿化方法促使可溶性Fe向次生铁矿物转变对酸性矿山废水(AMD)治理具有重要意义.化能自养菌A.ferrooxidans易受水流冲击而流失,常采用固定化方式来提高菌密度,从而保证较高的Fe^2+氧化和成矿速率以满足实际需要.本研究在相同初始条件下(pH=2.30、Fe^2+浓度4.48g/L、A.ferrooxidans密度8×10^6cells/mL)生物合成固定有A.ferrooxidans的施氏矿物、黄钾铁矾和黄铵铁矾,比较矿物溶解前(固定态)和溶解后(游离态)A.ferrooxidans的Fe^2+氧化性能,并分析各矿物对A.ferrooxidans的固定能力.结果表明,生物成因次生铁矿物干重排序为施氏矿物(0.24g)<黄铵铁矾(0.35g)<黄钾铁矾(0.67g),但矿物固定A.ferrooxidans的能力却依次为施氏矿物>黄铵铁矾>黄钾铁矾.以游离态A.ferrooxidans的Fe^2+氧化速率作为参比,推算出本研究所得施氏矿物、黄铵铁矾、黄钾铁矾固定A.ferrooxidans的有效生物量依次为5.33×10^7~5.33×10^8,5.72×10^6~5.72×10^7,6.35×10^6cells/g(干基).次生铁矿物载体有效生物量不仅直接影响AMD体系中Fe^2+氧化速度,也间接决定了总Fe的矿化去除效果.Biomineralization mediated by A.ferrooxidans to promotes the transformation of soluble Fe into secondary iron minerals is of great significance to the treatment of acid mine drainage(AMD).As a chemoautotrophic bacteria,A.ferrooxidans are vulnerable to hydraulic shock and loss.To ensure a higher Fe^2+oxidation and mineralization rate,immobilization method is often used to increase the bacterial density.In the study,schwertmannite,K-jarosite and NH4-jarosite immobilized with A.ferrooxidans were synthesized under the same initial conditions(pH=2.30,Fe^2+concentration 4.48g/L,and A.ferrooxidans density 8×10^6 cells/mL).The he Fe^2+oxidation properties of A.ferrooxidans before(fixed state)and after(free state)minerals dissolution and the A.ferrooxidans fixing ability on minerals were compared.Results indicated that the dry weight of biosynthesis minerals was schwertmannite(0.24g)<NH4-jarosite(0.35g)<K-jarosite(0.67g),however,A.ferrooxidans fixing ability was in the order of schwertmannite>NH4-jarosite>K-jarosite.According to the Fe^2+oxidation rate of free A.ferrooxidans,calculated the effective biomass of A.ferrooxidans immobilized by schwertmannite,NH4-jarosite and K-jarosite was 5.33×10^7~5.33×10^8,5.72×10^6~5.72×10^7,and 6.35×10^6 cells/g(dry basis),respectively.The effective biomass of secondary iron minerals not only directly affects the oxidation rate of Fe^2+,but also indirectly determines the mineralization removal effect of total Fe in AMD system.

关 键 词：氧化亚铁硫杆菌 次生铁矿物 固定化 FE^2+ 氧化及成矿性能 

分 类 号：X703[环境科学与工程—环境工程]