改性二氧化钛纳米管对水体中磷的吸附

利用硝酸铁对二氧化钛纳米管进行改性,并研究了改性二氧化钛纳米管对水中磷的吸附能力及吸附特征。结果表明,通过对二氧化钛纳米管的改性,提高了其对水中磷的吸附能力,磷去除率随着改性二氧化钛纳米管投加量的增加而提高,原水pH值对磷去除率影响不大;温度升高,磷去除率有所提高。进一步研究表明,改性二氧化钛纳米管对磷的吸附是一个快速吸附过程并可用准二级动力学模型进行很好的描述;热力学研究表明,改性二氧化钛纳米管对磷的吸附符合Freundlich等温吸附模型,ΔG0H0>0说明吸附反应是自发的吸热反应。

Adsorption of phosphate from aqueous solution by modified titanium oxide nanotubes

Modified titanium oxide nanotubes (TiNT) were successfully prepared by reacting TiNT with iron nitrate. The adsorption efficiency of TiNT for phosphate removal from wastewater was evaluated. The effects of the initial pH value, adsorbent dosage, and temperature on the phosphate removal rate were systematically studied. The results showed that the phosphate-uptake capacity of the modified TiNT was improved compared to that of unmodified TiNT. The removal rate of phosphate increased with increasing adsorbent dosage and temperature. The initial pH value had a slight effect on phosphate removal. The adsorption isotherm of phosphate removal by modified TiNT fitted well with the Freundlish isotherm model and the adsorption reaction was an easily spontaneous endothermic process, because ΔG0H0>0. In addition, adsorption kinetics showed that the adsorption of phosphate on modified TiNT was a fast adsorption process that was well-described by a pseudo-second-order model.