Department of Chemical Technology, Faculty of Sciences, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand.
Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand.
Sci Rep. 2021 Mar 11;11(1):5686. doi: 10.1038/s41598-021-84797-3.
The present study focused on the synthesis of copper hydroxide nanowires decorated on activated carbon (Cu(OH)-NWs-PVA-AC). The obtained Cu(OH)-NWs-PVA-AC Nano-composite was distinguished by XRD, SEM, EDX, BET, FTIR and XPS respectively. Besides, different variables such as solution p, and initial dye concentration, contact time, and temperature were performed on the adsorption efficiency of MB in a small batch reactor. Further, the experimental results are analyzed by various kinetic models via PFO, PSO, intra-particle diffusion and Elovich models, and the results revealed that among the kinetic models, PSO shows more suitability. In addition, different adsorption isotherms were applied to the obtained experimental data and found that Langmuir-Freundlich and Langmuir isotherm were best fits with the maximum adsorption capacity of 139.9 and 107.6 mg/g, respectively. The Nano-composite has outstanding MB removal efficiency of 94-98.5% with a span of 10 min. and decent adsorption of about 98.5% at a p of 10. Thermodynamic constants like Gibbs free energy, entropy, and enthalpy were analyzed from the temperature reliance. The results reveal the adsorption processes are spontaneous and exothermic in nature. The high negative value of ΔG° (- 44.11 to - 48.86 kJ/mol) and a low negative value of ΔH° (- 28.96 kJ/mol) show the feasibility and exothermic nature of the adsorption process. The synthesized dye was found to be an efficient adsorbent for the potential removal of cationic dye (methylene blue) from wastewater within a short time.
本研究专注于合成氧化铜纳米线修饰的活性炭 (Cu(OH)-NWs-PVA-AC)。通过 XRD、SEM、EDX、BET、FTIR 和 XPS 分别对所得 Cu(OH)-NWs-PVA-AC 纳米复合材料进行了区分。此外，在小批量反应器中，通过不同变量（如溶液 pH 值、初始染料浓度、接触时间和温度）对 MB 的吸附效率进行了研究。进一步，通过 PFO、PSO、内扩散和 Elovich 模型等动力学模型对实验结果进行了分析，结果表明，在动力学模型中，PSO 表现出更高的适用性。此外，不同的吸附等温线被应用于获得的实验数据，并发现 Langmuir-Freundlich 和 Langmuir 等温线与最大吸附容量 139.9 和 107.6 mg/g 最为吻合。该纳米复合材料对 MB 的去除效率高达 94-98.5%，时间跨度为 10 分钟。在 pH 值为 10 时，吸附量约为 98.5%。通过对温度的依赖关系分析了热力学常数，如吉布斯自由能、熵和焓。结果表明，吸附过程是自发的和放热的。ΔG°（-44.11 至-48.86 kJ/mol）的高负值和ΔH°（-28.96 kJ/mol）的低负值表明吸附过程是可行的且是放热的。该合成染料被发现是一种高效的吸附剂，可在短时间内从废水中有效去除阳离子染料（亚甲蓝）。
