In this work, a new method is proposed to remove Cr (III) in tanning wastewater with low cost bare magnetic Fe₃O₄ nanoparticles. It has achieved ultra-high chromium capture capacity under high selectivity. The maximum capture capacity of magnetic Fe₃O₄ nanoparticles for Cr (III) in chromium containing tanning wastewater is 456.20 mg/g at optimal pH 8. In a pilot scale apparatus running continuously at 18 L/h for 8 h, the chromium removal efficiency could be stabilized above 98.5% with chromium concentration reduced from 1065 mg/L to about 15 mg/L at the primary treatment. After secondary treatment, the outlet chromium concentration drops to 0.2 mg/L (lower than 0.5 mg/L, the maximum allowable concentration of Cr ^total in tanning wastewater determined by China), and the chromium removal efficiency is steadily above 97.8%. The results revealed that the method could be used economically as an efficient technique for removal of Cr (III) in chromium containing leather tanning wastewater and has great potential in heavy metal wastewater treatment.

在这项工作中，提出了一种使用低成本裸磁性 Fe ₃ O ₄纳米粒子去除制革废水中 Cr (III) 的新方法。它在高选择性下实现了超高的铬捕获能力。在最佳 pH 值为 8 时，磁性 Fe ₃ O ₄纳米颗粒对含铬制革废水中 Cr (III)的最大捕获能力为 456.20 mg/g。在以 18 L/h 连续运行 8 小时的中试规模设备中，铬去除率在初级处理时，铬浓度从 1065 mg/L 降低到约 15 mg/L，效率可以稳定在 98.5% 以上。二次处理后，出口铬浓度降至0.2mg/L（低于0.5mg/L，^总铬最大允许浓度）在我国确定的制革废水中），除铬效率稳定在97.8%以上。结果表明，该方法可作为一种有效去除含铬皮革鞣制废水中Cr(III)的技术，在重金属废水处理中具有巨大潜力。