loading纳米TiO2去除氟离子的性能
杨丽君;刘雪岩;姜鑫;李莹;常怀春;张蕾
【期刊名称】《应用化学》 【年(卷),期】2012(029)011
【摘要】研究了锐钛型纳米TiO2吸附剂对氟离子的吸附行为,考察了吸附平衡时间、温度、溶液的pH值等因素对吸附过程的影响.结果表明,纳米TiO2对氟离子的吸附在2.0 min基本达到平衡,在pH值2.0～10.0范围内,吸附率大于97％；吸附的氟离子可用0.1 mol/L NaOH溶液洗脱,3.0 min基本达到解析平衡,解析率能达到96％；该吸附过程符合准二级反应动力学模型,其反应的表观活化能(Ea)为6.85 kJ/mol;颗粒内扩散过程为吸附控制步骤,但不是唯一的控制步骤,同时还受液膜扩散的影响；吸附过程符合Langmuir、D-R等温模型,常温下纳米TiO2对氟离子的平均吸附能为4.26 kJ/mol.吸附反应的△G0＜0,焓变△H0＞0,说明该吸附过程是自发的吸热反应.共存阴离子HCO3-和pO43-对氟离子的吸附有影响.纳米TiO2在动态和静态吸附实验中的除氟效果相近.%Anatase titanium dioxide nanoparticles were employed for the adsorption of fluoride ions from aqueous solution. The process was studied in details by varying the pH value, adsorption time and temperature. The results showed that equilibrium was reached within 2. 0 min at room temperature. The adsorption efficiency was over 97% at pH 2. 0 ~ 10. 0. Adsorbed fluoride ions were desorbed with 0. 1 mol/L NaOH within 3. 0 min, while the desorption efficiency could be up to 96%. The kinetic experimental data properly correlate with the second-