School of Chemistry and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, PR China.
Hubei Provincial Academy of Eco-environmental Sciences, Wuhan 430072, PR China.
Int J Biol Macromol. 2024 Apr;264(Pt 1):130410. doi: 10.1016/j.ijbiomac.2024.130410. Epub 2024 Feb 27.
In this study, magnetic DTPA-modified chitosan composite microspheres (MDCM) were prepared by reverse emulsion-double crosslinking method (carbodiimide followed by glutaraldehyde) for removal of Pb(II) from aqueous solution. The obtained magnetic adsorbents were characterized by FTIR, SEM, XRD, VSM, BET, and C NMR. The effects of the pH, contact time, initial concentration, and competitive metal cations (Na(I), Ca(II), or Mg(II)) on Pb(II) adsorption were investigated. The results revealed that MDCM exhibited high removal performance over a wide pH range and in the presence of competitive metal cations. The maximum adsorption capacity of MDCM for Pb(II) is 214.63 mg g at pH 3, which is higher than most recently reported magnetic adsorbents. Adsorption kinetics and isotherms can be described by the pseudo-second-order model and Langmuir model, respectively. In addition, MDCM is easy to regenerate and can be reused five cycles with high adsorption capacity. Finally, the adsorption mechanism was further revealed by FTIR and XPS analysis. Overall, MDCM has practical application potential in removing Pb(II) from contaminated wastewater due to its high adsorption efficiency, good reusability, and convenient magnetic separation.
在这项研究中，通过反相乳液-双重交联法（碳二亚胺后接戊二醛）制备了磁性 DTPA 修饰壳聚糖复合微球（MDCM），用于从水溶液中去除 Pb(II)。所得到的磁性吸附剂通过 FTIR、SEM、XRD、VSM、BET 和 C NMR 进行了表征。考察了 pH 值、接触时间、初始浓度和竞争金属阳离子（Na(I)、Ca(II)或 Mg(II)）对 Pb(II)吸附的影响。结果表明，MDCM 在宽 pH 范围和存在竞争金属阳离子的情况下表现出高去除性能。在 pH 3 时，MDCM 对 Pb(II)的最大吸附容量为 214.63 mg g，高于最近报道的大多数磁性吸附剂。吸附动力学和等温线可以分别用伪二阶模型和 Langmuir 模型来描述。此外，MDCM 易于再生，可重复使用五次，且具有较高的吸附容量。最后，通过 FTIR 和 XPS 分析进一步揭示了吸附机理。总体而言，由于 MDCM 具有高吸附效率、良好的可重复使用性和方便的磁性分离，因此在去除废水中的 Pb(II)方面具有实际应用潜力。
