用磁性/β-环糊精/活性炭/海藻酸钠聚合物复合材料从水溶液中吸附阳离子染料、药物和金属:等温线、动力学和再生研究。
Adsorption of cationic dyes, drugs and metal from aqueous solutions using a polymer composite of magnetic/β-cyclodextrin/activated charcoal/Na alginate: Isotherm, kinetics and regeneration studies.
机构信息
Department of Chemistry, Govt. V.Y.T. PG Autonomous College Durg, 491001 Chhattisgarh, India.
Department of Chemistry, Govt. V.Y.T. PG Autonomous College Durg, 491001 Chhattisgarh, India.
出版信息
J Hazard Mater. 2021 May 5;409:124840. doi: 10.1016/j.jhazmat.2020.124840. Epub 2020 Dec 31.
In this work, we successfully synthesized novel polymer gel beads based on functionalized iron oxide (Fe3O4), activated charcoal (AC) particles with β-cyclodextrin (CD) and sodium alginate (SA) polymer (Fe3O4/CD/AC/SA), by a simple, reproducible and inexpensive method. These beads proved to be versatile and strong adsorbents with magnetic properties and high adsorption capacity. The composites were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, vibrating sample magnetometry, adsorption at -196 °C, high resolution transmission electron microscopy, thermogravimetric analysis and point of zero charge measurements. Two dyes, two drugs and one metal were used to test the adsorption capability of the prepared polymer nanocomposite. The adsorbent showed good removal efficiencies for the studied pollutants, especially the cationic dyes and the metal, when compared to other low-cost adsorbents. The saturated adsorption capacity of Fe3O4/CD/AC/SA reached 5.882 mg g-1 for methyl violet (MV), 2.283 mg g-1 for brilliant green (BG), 2.551 mg g-1 for norfloxacin (NOX), 3.125 mg g-1 for ciprofloxacin (CPX), 10.10 mg g-1 for copper metal ion (Cu(II)). The adsorption isotherm studies showed that data fitted well with Langmuir and Temkin isotherms models. The kinetic data showed good correlation coefficient with low error function for the pseudo-second order kinetic model. The data analysis was carried out using error and regression coefficient functions for the estimation of best-fitting isotherm and kinetic models, namely: chi-square test (χ2) and sum of the squares of errors (SSE). The activation energy was found to be 47.68 kJ mol-1 for BG, 29.09 kJ mol-1 for MV, 28.93 kJ mol-1 for NOX, 4.53 kJ mol-1 for CPX and 17.08 kJ mol-1 for Cu(II), which represent chemisorption and physisorption behavior of sorbent molecules. The polymer composites can be regenerated and easily separated from aqueous solution without any weight loss. After regeneration, the Fe3O4/CD/AC/SA beads still have good adsorption capacities up to four cycles of desorption and adsorption. The results indicate that the polymer gel beads are promising adsorbents for the removal of different categories of toxicants (like dyes, drugs and metal) in single adsorbate aqueous systems. Thus, the novel Fe3O4/CD/AC/SA beads can be effectively employed for a large-scale applications as environmentally compatible materials for the adsorption of different categories of pollutants.
在这项工作中,我们成功地合成了基于功能化氧化铁 (Fe3O4)、活性炭 (AC) 颗粒与β-环糊精 (CD) 和海藻酸钠 (SA) 聚合物 (Fe3O4/CD/AC/SA) 的新型聚合物凝胶珠,方法简单、可重复且成本低廉。这些珠子具有磁性和高吸附能力,是多功能且强吸附剂。通过傅里叶变换红外光谱、扫描电子显微镜、能谱、振动样品磁强计、-196°C 下的吸附、高分辨率透射电子显微镜、热重分析和零电荷点测量对复合材料进行了表征。使用两种染料、两种药物和一种金属来测试制备的聚合物纳米复合材料的吸附能力。与其他低成本吸附剂相比,该吸附剂对研究中的污染物具有良好的去除效率,特别是对阳离子染料和金属。Fe3O4/CD/AC/SA 的饱和吸附容量达到 5.882mg/g 对甲紫 (MV)、2.283mg/g 对亮绿 (BG)、2.551mg/g 对诺氟沙星 (NOX)、3.125mg/g 对环丙沙星 (CPX)、10.10mg/g 对铜离子 (Cu(II))。吸附等温线研究表明,数据与 Langmuir 和 Temkin 等温线模型拟合良好。动力学数据与准二级动力学模型的低误差函数具有良好的相关性。通过误差和回归系数函数对最佳拟合等温线和动力学模型进行数据分析,即:卡方检验 (χ2) 和误差平方和 (SSE)。BG 的活化能为 47.68kJ/mol,MV 为 29.09kJ/mol,NOX 为 28.93kJ/mol,CPX 为 4.53kJ/mol,Cu(II)为 17.08kJ/mol,这代表了吸附剂分子的化学吸附和物理吸附行为。聚合物复合材料可以在不损失任何重量的情况下再生并从水溶液中容易分离。再生后,Fe3O4/CD/AC/SA 珠仍具有良好的吸附能力,可达四次解吸和吸附循环。结果表明,聚合物凝胶珠是去除单一吸附物水体系中不同类别毒物(如染料、药物和金属)的有前途的吸附剂。因此,新型 Fe3O4/CD/AC/SA 珠可有效用作环境兼容材料,用于吸附不同类别污染物的大规模应用。