Batool Fozia, Kanwal Samia, Kanwal Hafsa, Noreen Sobia, Hodhod Mohamed S, Mustaqeem Muhammad, Sharif Gulnaz, Naeem Hafiza Komal, Zahid Javeria, Gaafar Abdel-Rhman Z
Institute of Chemistry, University of Sargodha, Sargodha 40100, Pakistan.
College of Biological Sciences and Medical Engineering, Donghua University, 2999 North Ren Min Road, Shanghai 201620, China.
Molecules. 2023 Oct 17;28(20):7124. doi: 10.3390/molecules28207124.
Addressing the growing need for methods for ecofriendly dye removal from aqueous media, this study explores the potential of rice husks coated with iron oxide (FeO@RH composites) for efficient Acid Blue 25 decontamination. The adsorption potential of Acid Blue 25 is analyzed using raw rice husks and FeO nanoparticles in the literature, but their enhanced removal capacity by means of FeO@RH composites is reported for the first time in this study. FeO@RH composites were analyzed by using analytical techniques such as TGA, SEM, FTIR, BET, and the point of zero charge (pH). The Acid Blue 25 adsorption experiment using FeO@RH composites showed maximum adsorption at an initial concentration of Acid Blue 25 of 80 ppm, a contact time of 50 min, a temperature of 313 K, 0.25 g of FeO@RH composites, and a pH of 2. The maximum percentage removal of Acid Blue 25 was found to be 91%. Various linear and nonlinear kinetic and isothermal models were used in this study to emphasize the importance and necessity of the adsorption process. Adsorption isotherms such as the Freundlich, Temkin, Langmuir, and Dubinin-Radushkevich (D-R) models were applied. The results showed that all the isotherms were best fitted on the data, except the linear form of the D-R isotherm. Adsorption kinetics such as the intraparticle kinetic model, the Elovich kinetic model, and the pseudo-first-order and pseudo-second-order models were applied. All the kinetic models were found to be best fitted on the data, except the PSO model (types II, III, and IV). Thermodynamic parameters such as ΔG° (KJ/mol), ΔH° (KJ/mol), and ΔS° (J/K*mol) were studied, and the reaction was found to be exothermic in nature with an increase in the entropy of the system, which supported the adsorption phenomenon. The current study contributes to a comprehensive understanding of the adsorption process and its underlying mechanisms through characterization, the optimization of the conditions, and the application of various models. The findings of the present study suggest practical applications of this method in wastewater treatment and environmental remediation.
为满足从水介质中去除染料的环保方法的需求不断增长，本研究探索了涂覆有氧化铁的稻壳（FeO@RH复合材料）对酸性蓝25进行高效去污的潜力。文献中使用生稻壳和FeO纳米颗粒分析了酸性蓝25的吸附潜力，但本研究首次报道了通过FeO@RH复合材料提高其去除能力。通过热重分析（TGA）、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、比表面积分析（BET）和零电荷点（pH）等分析技术对FeO@RH复合材料进行了分析。使用FeO@RH复合材料进行的酸性蓝25吸附实验表明，在酸性蓝25初始浓度为80 ppm、接触时间为50分钟、温度为313 K、FeO@RH复合材料用量为0.25 g且pH为2的条件下吸附量最大。酸性蓝25的最大去除率为91%。本研究使用了各种线性和非线性动力学及等温模型来强调吸附过程的重要性和必要性。应用了弗伦德利希（Freundlich）、坦金（Temkin）、朗缪尔（Langmuir）和杜宾宁-拉杜舍维奇（Dubinin-Radushkevich，D-R）等吸附等温模型。结果表明，除了D-R等温模型的线性形式外，所有等温模型都能很好地拟合数据。应用了颗粒内动力学模型、埃洛维奇（Elovich）动力学模型、准一级和准二级模型等吸附动力学模型。发现除了准二级模型（II、III和IV型）外，所有动力学模型都能很好地拟合数据。研究了诸如吉布斯自由能变（ΔG°，kJ/mol）、焓变（ΔH°，kJ/mol）和熵变（ΔS°，J/K*mol）等热力学参数，发现该反应本质上是放热的，且系统熵增加，这支持了吸附现象。当前研究通过表征、条件优化和各种模型的应用，有助于全面理解吸附过程及其潜在机制。本研究结果表明该方法在废水处理和环境修复方面具有实际应用价值。
