(北京科技大学 土木与环境工程学院，北京 100083)
摘 要: 为考察红城红球菌(Rhodococcus erythropolis，R. erythropolis)作为赤铁矿捕收剂使用的可能性及效果，对R. erythropolis形貌、细胞壁成分及其吸附前后赤铁矿、石英表面电性、疏水性进行分析，对赤铁矿、石英单矿物以及赤铁矿与石英矿1:1(质量比)混合矿进行浮选实验，对其在赤铁矿表面的吸附状况及吸附机理进行研究。结果表明，杆状R. erythropolis表面既含有非极性基团，又含有极性基团，使得其表面具有较高的负电性和较强的疏水性，因而对赤铁矿的吸附作用明显大于对石英的吸附作用。当以此细菌为捕收剂、在溶液pH值为6、R. erythropolis用量为75 mg/L时，赤铁矿的回收率为89.68%，而石英的回收率仅为26.25%。混合矿经过一次浮选，可获得铁品位和回收率分别为50.08%和76.41%的铁精矿。R. erythropolis在赤铁矿表面发生复杂的化学吸附且使赤铁矿颗粒形成疏水絮团，从而证实R. erythropolis可作为赤铁矿的捕收剂使用。
关键字: R. erythropolis；微生物；赤铁矿；石英；吸附；絮团；捕收剂
（School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:The possibility and effect of Rhodococcus erythropolis (R. erythropolis) as a flotation collector for hematite were investigated. The surface morphology and cell wall constituent of R. erythropolis were analyzed. The surface potentials of the strain, hematite and quartz before and after adsorption with R. erythropolis were measured. Flotation tests for the collection of pure hematite and pure quartz respectively and the separation of hematite-quartz mixture (1:1, mass ratio) were carried out. The adsorption characteristics and mechanisms were also discussed. The results show that the rod-shaped bacterium is detected with hydrophobic and hydrophilic groups on the cell wall, showing highly negative charged and strongly hydrophobic characteristics. The adsorption is significantly more selective onto hematite than onto quartz. The hematite recovery of 89.68% and quartz recovery of only 26.25% are obtained under solution pH value of 6 and cell concentration of 75 mg/L. Iron concentrate with the grade of 50.08% and recovery rate of 76.41% is recovered from the mixture after one-stag flotation. The chemical adsorption of the strain onto hematite makes hematite form hydrobolic agglomerate. It is confirmed that R. erythropolis can be acted as the collector for hematite.
Key words: Rhodococcus erythropolis; microorganisms; hematite; quartz; adsorption; agglomerate; collector
