【摘要】 赤泥对磷酸根离子具有吸附亲和力，可用于处理含磷废水，但单独使用时的除磷效果不理想，因此研究磷酸盐在赤泥表面润湿环境下的吸附动力学对研究赤泥吸附磷酸盐的机理具有重要意义。对赤泥的物相和晶体结构进行了定性和定量分析以及X射线能谱分析，发现赤泥中加藤石占比为39.11%。为了研究3种含磷酸盐水团簇在加藤石表面的吸附分布特征，基于密度泛函理论优化了加藤石的原始晶胞，并使用分子动力学模拟研究了含磷酸根离子水团簇在加藤石表面的吸附动力学。在含磷酸根离子水团簇吸附过程中，含磷酸根离子水团簇与加藤石表面之间的润湿膜逐渐变薄直至破裂，导致磷酸根离子均匀地吸附在加藤石表面，表明加藤石表面具有较好的润湿性。分析了不同含磷酸根离子水团簇在加藤石表面的吸附平衡构象以及加藤石中氧原子与含磷酸根离子水团簇中不同成分之间的径向分布函数，发现磷酸根离子在加藤石表面的稳定吸附受范德华力和氢键的共同影响。本研究成果有助于更好地解释磷酸盐在赤泥表面的吸附行为。更多还原

【Abstract】 The adsorption affinity of red mud to phosphate ions in wastewater was utilized to treat phosphate-bearing wastewater, but it did not work efficiently with red mud as only adsorbent to remove phosphate. Research of the adsorption dynamics of phosphate on the wetting red mud surface had a significant meaning to study the adsorption mechanism. Qualitative and quantitative analysis as well as X-ray energy spectrum analysis were undertaken on the phase and crystal structure of red mud.It was confirmed that the content of katoite in the red mud was 39.11%.In this study, the original unit cell of katoite was optimized based on density functional theory, and molecular dynamics simulation was employed to study the adsorption dynamics and characteristics of three phosphate-bearing water clusters on the katoite surface.During the adsorption of phosphate ion contained in water clusters, the wetting film between the clusters and the katoite surface gradually become thinner until breakage, resulting in the uniform adsorption of phosphate ions on the katoite surface, which exhibited high wettability on the katoite surface. Results of analysis of the adsorption equilibrium of different phosphate-bearing water clusters on the katoite surface and the radial distribution function between oxygen atoms in katoite and different components in phosphate-bearing water clusters showed that the stable adsorption of phosphate ions on the katoite surface is subject to the Van Edward force combined with hydrogen bonds.These findings may be conducive to better understanding of the adsorption behavior of phosphate on the red mud surface.更多还原