改性陶土颗粒吸附砷的实验研究

Experimental research on arsenic adsorption by modified ceramic granule

以赤玉土为骨料烧制陶土材料,经FeCl3溶液浸渍及热处理改性后制备成新型的改性陶土颗粒吸附剂,对其表面特征及除砷性能进行初步研究:BET测定得出该吸附剂比表面积为36.493m2/g,孔容量为0.070mL/g;SEMEDX显示吸附剂表面有大量铁、氧元素分布;对比该吸附剂和HCl溶液改性吸附剂表面的微观数码照片及3D影像图,表明该吸附剂表面存在大量铁氧化物;该吸附剂在中性pH范围内有良好吸附除砷能力,共存的氟离子、磷酸根离子对除砷效果有不同程度的竞争影响,碳酸根离子对除砷效果无显著影响;Freundlich等温线方程能较好地拟合As(V)的吸附过程(R2=0.9927),吸附平衡时的饱和吸附容量可达43.491mg/g。低成本高效的改性陶土颗粒应用于实际的砷吸附处理,具有较好的应用前景。

The modified ceramic granule（MCG）,which is a novel adsorbent for arsenic removal,was developed with a mixture of akadama mud,wheat starch,and Fe3O4,and modified using FeCl3 solution.The characteristics and adsorption properties of this adsorbent were studied in detail.The BET of MCG was 36.493 m2/g,and its pore volume was 0.070 mL/g.The SEM-EDX result showed that iron oxide was widely formed on the surface of MCG.The micro digital photos and 3D images of this adsorbent,compared with those of HCl-MCG,also indicated that a large amount of iron oxide was formed on the surface of the adsorbent.The adsorbent could be successfully used for arsenic removal in neutral pH ranges.The commonly presented fluoride and phosphate ions had different competing effects on arsenic removal,while carbonate had no significant effect.The Freundlich isotherm equation fit well with As（V） adsorption（R2=0.992？7）.The maximum adsorption capacity for As（V） was 43.491 mg/g.This cost-effective MCG has promising prospects for application to arsenic removal.