Department of Chemical Engineering, National Institute of Technology, Rourkela, 769008, Orissa, India.
Environ Res. 2022 Nov;214(Pt 3):114044. doi: 10.1016/j.envres.2022.114044. Epub 2022 Aug 17.
The development of agricultural activities and industrialization recently has various adverse impacts on living organisms. The ever-increasing problem of organic pollution has been an environmental concern to the community. Among these, phenolic pollutants like 2,4-dichlorophenol (2,4-DCP), phenol, 2-chlorophenol (2-CP), and bisphenol-A (BPA) are priority toxic pollutants that are continuously released into environment from many industries. In this work, a biocompatible zinc oxide incorporated polyethylene glycol functionalized reduced graphene oxide composite (RGO-PEG-ZnO) was synthesized and explored for the adsorptive removal of toxic phenolic pollutants from water. The optimized adsorption parameters were solution pH 7, adsorption time 60 min, temperature 25 °C, and dosage 0.25 g/L. The isotherms were well fitted by the Langmuir model for BPA and phenol, whereas for 2-CP, and 2,4-DCP, Freundlich was the best-fitted model, and the maximum uptake of BPA, phenol, 2-CP, and 2,4-DCP were 485.756, 511.248, 531.804, 570.641 mg/g, respectively. The kinetic data for all the phenolic pollutants follow the pseudo-second-order model. The thermodynamic analysis shows that Gibb's free energy (ΔG) values for all the pollutants were negative, confirming that the process was spontaneous. The positive values of change in enthalpy (ΔH) 28.261, 37.205, 46.182, and 61.682 kJ/mol for BPA, phenol, 2-CP, and 2,4-DCP, respectively, confirm that the above adsorption process was endothermic. The composite can be used for up to five cycles with a small reduction in the removal percentage. Adsorption performance of the synthesized composite for synthetic industrial effluents shows that up to 86.54% removal occurred in 45 min adsorption time. Based on the remarkably rapid adsorption and high adsorption capacity, RGO-PEG-ZnO composite can be considered an efficient adsorbent for treating phenolic pollutants from wastewater.
最近，农业活动和工业化的发展对生物产生了各种不利影响。有机污染问题日益严重，引起了社会的关注。在这些污染物中，苯酚类污染物如 2,4-二氯苯酚（2,4-DCP）、苯酚、2-氯苯酚（2-CP）和双酚 A（BPA）是优先毒性污染物，它们不断从许多工业中释放到环境中。在这项工作中，合成了一种生物相容性的氧化锌掺入聚乙二醇功能化还原氧化石墨烯复合材料（RGO-PEG-ZnO），并探索其用于从水中吸附去除有毒的苯酚类污染物。优化的吸附参数为溶液 pH 值 7、吸附时间 60 分钟、温度 25°C 和剂量 0.25 g/L。等温线模型对 BPA 和苯酚的拟合较好，而对 2-CP 和 2,4-DCP 的拟合较好的模型是 Freundlich 模型，BPA、苯酚、2-CP 和 2,4-DCP 的最大吸附量分别为 485.756、511.248、531.804 和 570.641 mg/g。所有苯酚类污染物的动力学数据均符合准二级模型。热力学分析表明，所有污染物的吉布斯自由能（ΔG）值均为负值，证实该过程是自发的。BPA、苯酚、2-CP 和 2,4-DCP 的焓变（ΔH）值分别为 28.261、37.205、46.182 和 61.682 kJ/mol，均为正值，证实上述吸附过程是吸热的。该复合材料可重复使用五轮，去除率仅略有下降。合成复合材料对合成工业废水的吸附性能表明，在 45 分钟的吸附时间内，去除率可达 86.54%。基于快速吸附和高吸附容量，RGO-PEG-ZnO 复合材料可被视为处理废水中苯酚类污染物的有效吸附剂。
