(北京科技大學 土木與環(huán)境工程學院，北京 100083)
摘 要: 為考察紅城紅球菌(Rhodococcus erythropolis，R. erythropolis)作為赤鐵礦捕收劑使用的可能性及效果，對R. erythropolis形貌、細胞壁成分及其吸附前后赤鐵礦、石英表面電性、疏水性進行分析，對赤鐵礦、石英單礦物以及赤鐵礦與石英礦1:1(質(zhì)量比)混合礦進行浮選實驗，對其在赤鐵礦表面的吸附狀況及吸附機理進行研究。結(jié)果表明，桿狀R. erythropolis表面既含有非極性基團，又含有極性基團，使得其表面具有較高的負電性和較強的疏水性，因而對赤鐵礦的吸附作用明顯大于對石英的吸附作用。當以此細菌為捕收劑、在溶液pH值為6、R. erythropolis用量為75 mg/L時，赤鐵礦的回收率為89.68%，而石英的回收率僅為26.25%。混合礦經(jīng)過一次浮選，可獲得鐵品位和回收率分別為50.08%和76.41%的鐵精礦。R. erythropolis在赤鐵礦表面發(fā)生復雜的化學吸附且使赤鐵礦顆粒形成疏水絮團，從而證實R. erythropolis可作為赤鐵礦的捕收劑使用。
關(guān)鍵字: R. erythropolis；微生物；赤鐵礦；石英；吸附；絮團；捕收劑
（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
