异化金属还原菌还原赤铁矿研究  

Iron reduction of hematite by dissimilatory iron-reducing bacteria

作　　者：冯雅丽[1] 王李娟[1,2] 李浩然[2] 张茜[1,2] 张士元[1,2] 毕耜超[1,2] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]中国科学院过程工程研究所生化工程国家重点实验室,北京100190

出　　处：《中南大学学报（自然科学版）》2013年第5期1754-1759,共6页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(2117624221176026);国家"十二五"支撑项目(2012BAB14B05;2012BAB07B05);国家高技术研究发展计划("863"计划)项目(2012AA062401);"十二五"国家长远发展专项(DY125-15-T-08)

摘　　要：以实验室自制氢氧化铁为电子受体,醋酸钠为电子供体,从厌氧活性污泥中分离得到异化金属还原菌。将赤铁矿代替氢氧化铁作为电子受体对微生物进行驯化。通过单因素实验考察好氧、厌氧条件及pH、温度对反应过程的影响,并对反应机理进行研究。研究结果表明:赤铁矿颗粒逐渐由红色变深至棕黑色并具有磁性,分析表明异化金属还原菌可将赤铁矿中的Fe(Ⅲ)还原成Fe(Ⅱ),但反应不完全。反应生成的棕黑色颗粒物质主要成分为Fe3O4与Fe2O3的混合物;厌氧条件优于好氧条件,在温度为30℃,振荡速度为160 r/min,接种量为10%,pH为5.0,赤铁矿加入量为1.0 g/L的条件下,20 d后,Fe(Ⅱ)的浓度可达1.87 mmol/L,赤铁矿中的部分Fe(Ⅲ)还原为Fe(Ⅱ),在矿物颗粒表面沉积并与其结合反应生成磁铁矿(Fe3O4),增强了原矿的磁性。An experimental system was developed for the study of iron reduction of hematite by dissimilatory iron-reducing bacteria （DIRB）. Using ferric hydroxide as the electron acceptor and sodium acetate as the electron donor, dissimilatory iron-reducing bacteria was isolated from anaerobic activated sludge. Instead of ferric hydroxide, hematite was used as the electron acceptor for microbial acclimation. The effects of aerobic and anaerobic conditions, pH values and temperature on the iron reduction of hematite were studied by single-factor experiments, then the mechanism of reaction and the feasibility of applications were discussed. The results indicate that the color of hematite particles turn from red to nigger-brown and black gradually and the particles become magnetic. Analysis indicated that Fe（Ⅲ） in hematite can be reduced to Fe（Ⅱ） by dissimilatory iron-reducing bacteria, but the reaction is incomplete. The nigger-brown and black particles are a blend of Fe304 and Fe203, anaerobic conditions are more beneficial than aerobic conditions for iron reduction. With 160 r/min of shaking speed, 10% of appropriate inoculation, 1.0 g/L of hematite additive amount, 30 ℃ of temperature and 5.0 of pH, the concentration of Fe（Ⅱ） can be increase to 1.87 mmol/L after 20 d. Fe（ Ⅱ） is combined with Fe（Ⅲ） in hematite to form magnetite （Fe304） which deposited on the mineral surface. The surface magnetism of hematite is enhanced in this work.

关 键 词：赤铁矿 异化金属还原菌 异化还原 磁化 

分 类 号：TD921[矿业工程—选矿] Q939.97[生物学—微生物学]