Abstract Bio-flotation is a method used biological organisms to replace harmful chemicals for processing ores, and realized avoiding environmental and safety issues. In this study, the flotation separation of magnetite and phlogopite was examined using biological reagent obtained from Paenibacillus amylolyticus. Micro-flotation experiments were performed by two flotation modes: bacteria pretreatment mineral (Ⅰ) and using the suspension of mineral and bacterial culture at different growth phase (Ⅱ). The test results of flotation mode (Ⅰ) showed that biological reagent exhibited high effectiveness in separation of magnetite and phlogopite. On the other hand, flotation mode (Ⅱ) obtained the best result regarding the iron grade of concentrate 69.56% by using the bacteria culture growth phases of 8 d, being highly competitive as compared to mode (Ⅰ). For both flotation mode, flotation separation was driven by the selective adsorption of bacterial cells and metabolic products (including proteins and polysaccharides) mechanism. The results from analysis of SEM, Zeta potential measurements and the adsorption behavior of bacteria metabolites on mineral surfaces clearly showed that bacterial cells exhibited higher adsorption density on the magnetite surface than phlogopite in flotation mode (Ⅰ), and extracellular polysaccharide illustrated a higher adsorption density on magnetite, making it more hydrophilic in flotation mode (Ⅱ).

中文翻译：

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解淀粉类芽孢杆菌生物浮选药剂在磁铁矿和金云母浮选体系中的评价

摘要 生物浮选是一种利用生物有机体替代有害化学物质来处理矿石，实现避免环境和安全问题的方法。在这项研究中，使用从解淀粉芽孢杆菌中获得的生物试剂检查了磁铁矿和金云母的浮选分离。微浮选实验采用两种浮选方式：细菌预处理矿物（Ⅰ）和使用不同生长期矿物和细菌培养物的悬浮液（Ⅱ）。浮选模式（Ⅰ）的试验结果表明，生物试剂在分离磁铁矿和金云母方面表现出很高的效率。另一方面，浮选模式（Ⅱ）使用8 d的细菌培养生长期获得了精矿铁品位69.56%的最佳结果，与模式（Ⅰ）相比具有很强的竞争力。对于两种浮选模式，浮选分离是由细菌细胞和代谢产物（包括蛋白质和多糖）的选择性吸附机制驱动的。SEM、Zeta电位测量和细菌代谢物在矿物表面的吸附行为分析结果清楚地表明，细菌细胞在浮选模式下在磁铁矿表面的吸附密度高于金云母（Ⅰ），胞外多糖表现出更高的吸附密度在磁铁矿上，使其在浮选模式下更具亲水性（Ⅱ）。