铁还原菌RBFL分离鉴定及其去除高岭土中Fe_2O_3

Study on the Isolation and Identification of an Iron-reducing Bacterium RBFL and the Fe_2O_3 Removal of its from Kaolin

以高岭土为选择性培养基,从高岭土矿样品中分离到一株铁还原菌RBFL.经形态特征观察、生理生化特征和16S r DNA序列分析,鉴定其为短小芽孢杆菌(Bacillus pumilus).考察了以葡萄糖、蔗糖、麦芽糖、淀粉为碳源对RBFL菌还原高岭土中Fe2O3(Fe3+)的影响,结果表明葡萄糖作为碳源,高岭土除铁效果最好,在葡萄糖质量分数为1%、矿浆质量分数为10%、铁还原菌液质量分数为5%、温度为30℃条件下厌氧培养7 d,高岭土中Fe3+去除率为44.94%,Fe2O3含量由0.89%降低至0.49%,自然白度由61.3提高至67.5,1 280℃烧成白度由84.9提高至90.1.

Kaolin was chosen as the selective media. An iron-reducing bacterium RBFL was i- solated from kaolinic ore sample and was identified as Bacillus pumilus according to its morphology feature, physiological and biochemical characteristics and 16S rDNA analysis. In addition, carbon souses, including glucose, sucrose, maltose and starch, impacting on the iron removal from kaolin using ion reducing bacteria were investigated with batch experiments. The results showed that glu- cose emerged as the most effective carbon source. Under the conditions with glucose as carbon source, glucose mass concentration of 1%, pulp mass concentration of 10%, bacterial inoculum mass concentration of 5% , temperature of 30 ℃, anaerobic culture for 7 days, the removal percent- age of Fe3＋ from kaolin was achieved 44.94% , Fe2O3 content in kaolin was reduced from 0. 89% to 0.49% , the natural whiteness was enhanced from 61.3 to 67.5, and whiteness was enhanced from 84.9 to 90. 1 after fired at 1 280 ℃.