利用浸渍法对纳米TiO2进行表面改性,制备出改性纳米TiO2,扫描电镜(SEM)对其进行了表征,并以其为吸附剂,以电感耦合等离子体原子发射光谱(ICP—AES)法为分析手段,探讨了改性纳米TiO2在静态吸附条件下对Mo(Ⅵ)的吸附性能。考察了影响其吸附和解脱的主要因素及Mo(Ⅵ)的吸附等温线,研究了常见共存离子的影响,并做了选择性比较实验。结果表明:在pH2.0,振荡8min,静置2h条件下,改性纳米TiO:对Mo(Ⅵ)的吸附率可达到93.0%以上;10mL 0.1mol/L NaOH作为解脱剂可使Mo(Ⅵ)定量解脱;与未负载的纳米TiO2相比,改性纳米TiO2对Mo(Ⅵ)的吸附性能良好,选择性更好。该指示剂已用于水样中钼的测定。
The modified nano-titanium dioxide as a solid sorbent was prepared by impregnation method and characterized by SEM. The adsorption behavior of the sorbent to Mo(VD in static system was studied by inductively coupled plasma atomic emission spectrometry (ICP-AES). The main factors affecting the adsorption and desorption of Mo(Ⅵ) were determined along with the adsorption isotherms and the effect of coexisting ions. A comparison experiment was conducted to test the selectivity. The results showed that, when the test solution containing the sorbent was vibrated for 8 min and placed statically for 2 h at pH 2.0, the adsorption rate of the sorbent to Mo(Ⅵ) could up to at least 93.0 %. Mo(Ⅵ)adsorbed onto the sorbent could be desorbed with 10 mL of 0. 1 mol/L NaOH. Compared with nano-titanium dioxide without modification, the modified TiO2 exhibited better adsorptivity as well as better selectivity. It has been applied to the analysis of Mo(Ⅵ) in environmental water samples.