欢迎访问《高校地质学报》官方网站,今天是
分享到:

高校地质学报 ›› 2024, Vol. 30 ›› Issue (05): 505-513.DOI: 10.16108/j.issn1006-7493.2023046

• •    下一篇

铈铝氧化物对磷酸根离子的吸附行为和机制研究

聂宏达1,任 超1, 2,李 伟1*   

  1. 1. 表生地球化学教育部重点实验室,南京大学 地球科学与工程学院,南京 210023;
    2. 南京理工大学 环境与生物工程学院,南京 210094
  • 出版日期:2024-10-20 发布日期:2024-10-20

Macroscopic and Spectroscopic Study on Phosphate Adsorption by Ce-Al Oxide

NIE Hongda1,REN Chao1,2,LI Wei1*   

  1. 1. Key Laboratory of Surficial Geochemistry Ministry Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China;
    2. School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
  • Online:2024-10-20 Published:2024-10-20

摘要: 中国和世界上许多国家(地区)都面临着水体磷超标引起的富营养化问题,因此研究磷的环境地球化学行为以及探索除磷技术和原理至关重要。文章以人工合成的铈铝氧化物作为吸附剂材料,研究了铈铝氧化物对磷酸根离子的宏观吸附行为和微观分子机制,考查反应时间、初始磷浓度和pH等外部条件对磷酸根在铈铝氧化物表面吸附行为和机制的影响。研究结果表明,铈铝氧化物对磷酸根的吸附在24 h内达到平衡;磷酸根的吸附等温线满足Langmuir模型,理论最大吸附量为75.5 mg·g-1;吸附量不随pH变化,在pH=3~10范围内均能保持较高的吸附性能。该研究进一步采用zeta点位测量、显微分析(SEM、TEM)和谱学方法(XRD、XPS)等手段,揭示了磷酸根在铈铝氧化物表面的吸附以形成内圈吸附和表面沉淀两种机制为主。该研究结果将为稀土基矿物改性材料的除磷应用提供理论指导。

关键词: 铈铝氧化物, 磷酸根, 吸附, 吸附机制, XPS

Abstract: Eutrophication caused by excess phosphate in water bodies is an important issue in China and many countries (regions) around the world. Therefore, it is crucial to investigate the environmental geochemical behavior of phosphate and to explore phosphorus removal techniques and principles. In this study, a Ce-Al oxide was synthesized as the adsorbent material to investigate the adsorption behavior and mechanism of orthophosphate. The effects of system parameters such as reaction time, initial phosphate concentration, pH and ionic strength on the phosphate adsorption by the Ce-Al oxide were examined. The results showed that the phosphate adsorption reached equilibrium within 24 hours; the adsorption isotherm (pH=7) was best fitted by Langmuir adsorption mode, yielding a maximum adsorption amount of 75.5 mg·g-1; and importantly the adsorption was insensitive to pH and maintained a high efficiency in the studied pH range (i.e. pH=3-10). This study further employed zeta potential measurement, microscopic analyses (SEM and TEM) and spectroscopic methods (XRD and XPS) to investigate the phosphate adsorption mechanisms by the Ce-Al oxide. It can be concluded that surface precipitation and inner-sphere adsorption dominates the phosphate adsorption mechanisms by the Ce-Al oxide. The study demonstrates that the Ce-Al oxide is a candidate material for phosphate removal.

Key words: Ce-Al oxide, phosphate, adsorption, adsorption mechanism, XPS

中图分类号: