摘要：

介绍了一种新型水处理剂———氢氧化铝镁正电纳米材料 (AMH)。研究了AMH对水溶液中Cr(Ⅵ )的吸附性能,考察了吸附时间、pH值、SO₄ ^2-、Cr(Ⅵ )浓度对吸附的影响。静态吸附实验结果表明,吸附可以在 4min之内达到平衡 ；在 pH值 5～ 7时吸附效果最好 ;随着Cr(Ⅵ )浓度的增大吸附量逐渐增大,最大吸附量达 110mg/g ；吸附不受SO₄ ^2-的影响。吸附等温线符合Freundlich模式,吸附机理主要为离子交换吸附,Cr(Ⅵ )主要以CrC₂ O₇^2-的形式被吸附。AMH可以用硅凝胶法造粒。动态吸附实验表明,对于 10 0mg/L的含铬废水,颗粒吸附剂的饱和吸附量为 1.96mg/ g(以Cr计 )。吸附剂用0.2mol/LFeCl₂ 的酸性溶液进行再生,再生效率达 100 %。

关键词: 氢氧化铝镁, 纳米材料, 含铬废水, 吸附

Abstract:

A new type of water treatment agent, aluminum-magnesium hydro xide positive nanomaterial(AMH)is introduced.The adsorption perfo rmance of Cr(Ⅵ)on AMH and the effect of the adsorption time, pH,SO₄^2- and Cr(Ⅵ )concentration on the adsoption have been studied.The result s of static test show that the adsorption equilibrium is reached within 4 minutes, the adsorption efficiency is higher in the range of pH 5 ～7,the adsorption amount increases steadily along with the concentration of Cr(Ⅵ )and the maximum adsorption amount is 110 mg/g, SO₄^2- has no influence on the adsorption.The adsorption is other maccords with Freundlich mode.The adsorption mechanism is mainly of ions exchange adsorption.Cr(Ⅵ)is adsorbed chiefly in the form of Cr₂O₇^2-.The particulate adsorbent of AMH is made by silica gel method.The dynamic test indicates that the saturated adsorption amount of the particulate adso rbent is 1.96 mg/g for the chromium-containing wastewater of 100 mg/L.The adsorbent can be regenerated with the acidic solution of 0.2 mol/L FeCl₂.

Key words: aluminum-magnesium hydroxide, nanomaterial, chromium-containing wastewater, adsorpt ion

中图分类号: 

• O611.64