【摘要】 【目的】以陕西杨凌某自来水厂铝污泥（Al-WTRs）为原料,对其进行改性,研究改性后铝污泥对Pb²⁺和Cu²⁺的吸附性能,以期为Al-WTRs的利用提供途径。【方法】采用KMnO₄和FeCl₂·4H₂O对Al-WTRs进行改性,制备铁锰氧化物改性铝污泥（M-Al-WTRs）,采用比表面（BET-N2）、扫描电镜（SEM-EDS）、X射线衍射（XRD）、红外光谱（FTIR）等方法对改性前后Al-WTRs进行表征分析,并探讨不同pH、吸附时间、重金属初始质量浓度、温度和离子强度等条件下M-Al-WTRs对Pb²⁺和Cu²⁺的吸附性能。【结果】与Al-WTRs（9.10m²/g）相比,M-Al-WTRs比表面积显著增大到100.8m²/g;SEM-EDS、XRD、FTIR分析结果显示,M-Al-WTRs表面粗糙,且负载许多颗粒,并保持无定形态。M-Al-WTRs对Pb²⁺和Cu²⁺的吸附量随着pH的增加逐渐增大,最终趋于稳定,其中当pH=5时,M-Al-WTRs对Pb²⁺和Cu²⁺的吸附量分别为67.18和20.81mg/g,分别比Al-WTRs提高了109.1%和68.64%。M-Al-WTRs对Pb²⁺和Cu²⁺的吸附动力学符合准二级吸附动力学模型,吸附等温线符合Langmuir等温模型。热力学分析表明,M-Al-WTRs对Pb²⁺和Cu²⁺的吸附是自发、吸热、增熵的过程。M-Al-WTRs对Pb²⁺和Cu²⁺的吸附几乎不受离子强度的影响,属于专性吸附。【结论】成功制备了对Pb²⁺和Cu²⁺具有良好吸附效果的M-Al-WTRs。更多还原

【Abstract】 【Objective】The adsorption of Pb²⁺and Cu²⁺on modified alum water treatment residuals were investigated to improve the utilization of Al-WTRs.【Method】Al-WTRs from a water plant in Yang ling,Shaanxi were modified by KMnO₄and FeCl₂·4H₂O to obtain M-Al-WTRs.Adsorbents（Al-WTRs and M-Al-WTRs）were characterized by BET-N2,SEM-EDS,XRD and FTIR.Batch adsorption experiments were conducted to investigate the effects of pH,adsorption time,initial mass concentration of heavy metals,temperature and ion strength on adsorption properties of Pb²⁺and Cu²⁺by M-Al-WTRs.【Result】Compared with Al-WTRs（9.10m²/g）,specific surface of M-Al-WTRs was significantly increased to 100.8m²/g.SEM-EDS,XRD,and FTIR showed that the surface of M-Al-WTRs was rough and loaded with many particles,and the amorphous structure was well maintained after modification.Adsorption capacities of Pb²⁺and Cu²⁺on M-Al-WTRs increased with increasing pH and reached steady gradually.When pH=5,the adsorption capacities of Pb²⁺and Cu²⁺on M-Al-WTRs were 67.18and 20.81 mg/g,which were109.1%and 68.64%higher than that of Al-WTRs,respectively.The adsorption of Pb²⁺and Cu²⁺by M-Al-WTRs could be described with the pseudo-second-order kinetic model,and the adsorption isotherm fitted Langmuir model well.Thermodynamic analysis showed that the adsorption process of Pb²⁺and Cu²⁺on M-Al-WTRs was spontaneous,endothermic and entropy increasing.The adsorption of Pb²⁺and Cu²⁺on M-Al-WTRs was hardly affected by ionic strength.【Conclusion】M-Al-WTRs with relative good adsorption capacities of Pb²⁺and Cu²⁺could be prepared by alum water treatment residuals.更多还原