摘要：

以价格低廉的葡萄糖为模板剂，合成了磁性介孔γ-Fe₂O₃，其比表面积为99.97 m²/g，平均孔容为0.25 cm³/g，孔径为33 nm。 采用批量平衡试验，研究了300 K下介孔γ-Fe₂O₃对Cr（Ⅵ）的吸附特性和介孔γ-Fe₂O₃的再生及Cr（Ⅵ）的回收。试验结果表明：pH 为3.5时，介孔γ-Fe₂O₃对Cr（Ⅵ）的饱和吸附量达到44.56 mg/g。Freundlich方程比Langmuir方程更好地描述了介孔γ-Fe₂O₃吸附Cr（Ⅵ）的行为，表明此吸附是多分子层物理吸附。300 K下，用0.01 mol/L 的NaOH 处理吸附有Cr（Ⅵ）的介孔γ-Fe₂O₃，可以实现介孔γ-Fe₂O₃的很好再生。再生的γ-Fe₂O₃经过5次循环使用，仍具有很好的吸附能力。

关键词: 介孔γ-Fe₂O₃, 吸附, 含Cr（Ⅵ）废水, 磁性分离

Abstract:

Magnetic mesoporous γ-Fe₂O₃, having a specific surface area of 99.97 m²/g, average pore volume of 0.25 cm³/g and pore diameter of 33 nm, has been prepared in the presence of cheap glucose as a template. Using batch equilibration technique, the adsorption behavior of Cr(Ⅵ) onto mesoporous γ-Fe₂O₃, the regeneration of mesoporous γ-Fe₂O₃ and the recovery of Cr(Ⅵ) are studied at 300 K. The results indicate that saturation adsorption capacity of Cr(Ⅵ) onto mesoporous γ-Fe₂O₃ reaches 44.56 mg/g when pH is 3.5. Freundlich equation can describe the Cr(Ⅵ) adsorption behavior by magnetic mesoporous γ-Fe₂O₃ better than Langmuir equation does, indicating that it is multi-molecular layer physical adsorption. Moreover, the regeneration of mesoporous γ-Fe₂O₃ can be realized well by using NaOH(0.01 mol/L) for adsorbing Cr(Ⅵ)-loaded mesoporous γ-Fe₂O₃. The regenerated γ-Fe₂O₃ still keeps its original adsorption capacity very well after being reused circularly for five times.

Key words: mesoporous iron-oxide, adsorption, wastewater containted Cr(Ⅵ), magnetic separation

中图分类号: 

• X703