Liu Honglei, Sun Xiaofei, Yin Chengqing, Hu Chun
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 10085, China.
J Hazard Mater. 2008 Mar 1;151(2-3):616-22. doi: 10.1016/j.jhazmat.2007.06.033. Epub 2007 Jun 14.
A type of mesoporous ZrO2 was synthesized and its phosphate removal potential was investigated in this study. The adsorption isotherm, pH effect, ionic strength effect and desorption were examined in batch experiments. The adsorption data fitted well to the Langmuir model with which the maximum P adsorption capacity was estimated to be 29.71 mgP/g. The amount of phosphate adsorbed increased rapidly in the first 5 h and slowly towards the end of the run, suggesting the possible monolayer coverage of phosphate ions on the surface of the adsorbent. The phosphate adsorption tended to increase with a decrease of pH and an increase of ionic strength. A phosphate desorbability of approximately 60% was observed with 0.5 M NaOH, which indicated a relatively strong bonding between the adsorbed PO4(3-) and the sorptive sites on the surface of the adsorbent. The immobilization of phosphate probably occurs by the mechanisms of ion exchange and physicochemical attraction. Due to its high adsorption capacity, this type of Zirconium oxide has the potential for application to control phosphorus pollution.
本研究合成了一种介孔ZrO₂，并对其除磷潜力进行了研究。在批量实验中考察了吸附等温线、pH效应、离子强度效应和解吸情况。吸附数据与Langmuir模型拟合良好，据此估计最大磷吸附容量为29.71 mgP/g。在前5小时内，吸附的磷量迅速增加，运行结束时增加缓慢，这表明磷酸根离子可能在吸附剂表面形成单层覆盖。磷酸盐吸附倾向于随着pH值的降低和离子强度的增加而增加。用0.5 M NaOH观察到约60%的磷酸盐解吸率，这表明吸附的PO₄³⁻与吸附剂表面的吸附位点之间存在相对较强的结合。磷酸盐的固定化可能通过离子交换和物理化学吸引机制发生。由于其高吸附容量，这种类型的氧化锆具有控制磷污染的应用潜力。
