8-HQ纳米纤维对水体中Cr(Ⅵ)的超高吸附性能

Super-high adsorption performance of 8 HQ Nanofiber for Cr(Ⅵ)ions in aqueous solution

为实现电镀过程中高毒性含Cr(Ⅵ)废水的深度处理,研究以8-羟基喹啉纳米纤维(8-HQ纳米纤维)为吸附材料,系统研究了废水中Cr(Ⅵ)的去除性能。动力学试验显示,吸附过程符合准二级吸附模型,并在90 min内达到吸附平衡;等温线试验显示,该材料对Cr(Ⅵ)的最大吸附容量为460 mg/g,且该吸附过程符合Langmuir吸附模型。此外,该材料在K(Ⅰ)、Na(Ⅰ)、Mg(Ⅱ)、Ca(Ⅱ)、Ni(Ⅱ)和Cu(Ⅱ)共存条件下,对Cr(Ⅵ)仍具有较好的选择性。此外,在6次再生循环后,8-HQ纳米纤维对Cr(Ⅵ)仍保持较好吸附效果。通过傅里叶变换红外光谱(Fourier Transform Infrared Spectrogram)、扫描电子显微镜(Scanning Electron Microscope)、X射线光电子能谱(X-ray Photoelectron Spectroscopy)、热重分析(Thermogravimetric Analysis)探究吸附位点与Cr(Ⅵ)的作用机理。研究对处理极端体系下的含Cr(Ⅵ)废水提供了新途径,并具有工业应用前景。

Chromium is extensively utilized in electroplating and various industries owing to its exceptional physicochemical characteristics.Nevertheless,the electroplating operations result in the annual discharge of a substantial volume of Cr(Ⅵ)containing wastewater,characterized by high toxicity,into the natural environment,posing a significant threat to the ecosystem.To address the challenge of effectively treating highly toxic Cr(Ⅵ)containing wastewater generated during electroplating processes,this study meticulously examines the removal efficacy of Cr(Ⅵ)from wastewater using 8-hydroxyquinoline nanofiber(8 HQ Nanofiber)as an adsorbent.The paper comprehensively investigates the pertinent performance of 8 HQ Nanofiber in relation to Cr(Ⅵ)ions through a range of experiments,including analyses of pH effects,isotherm characteristics,kinetics,ion coexistence,and cyclic regeneration.The findings reveal that in highly acidic conditions,the 8 HQ Nanofiber consistently demonstrates exceptional adsorption capabilities towards Cr(Ⅵ)ions.Notably,it exhibits a significantly higher maximum adsorption capacity of 460 mg/g compared to the majority of other adsorbents.Moreover,equilibrium adsorption is achieved within a short period of 90 minutes.The adsorption behavior of the 8 HQ Nanofiber towards Cr(Ⅵ)ions adheres to the Langmuir adsorption and pseudo-second-order models,indicating a monomolecular layer adsorption process with chemisorption characteristics.The interaction mechanism between the functional sites and Cr(Ⅵ)ions was investigated through Fourier Transform Infrared Spectroscopy(FT IR),Scanning Electron Microscopy(SEM),X-ray Photoelectron Spectroscopy(XPS),and Thermogravimetric Analysis(TGA).The results suggest that the N and O functional atoms form coordination bonds with Cr(Ⅵ)ions,delineating a potential mechanism underlying the adsorption process.Furthermore,the material demonstrates exceptional selectivity for Cr(Ⅵ)ions even in the presence of K(Ⅰ),Na(Ⅰ),Mg(Ⅱ),Ca(Ⅱ),Ni(Ⅱ),and Cu(Ⅱ)ions.It continues to exhibit strong adsorption capabilities for Cr(Ⅵ)ions after 6 regeneration cycles,highlighting its potential as an effective adsorption material.Overall,the 8 HQ Nanofiber presents a promising solution for wastewater containing highly toxic Cr(Ⅵ)ions,with the possibility of industrial applications.This study therefore offers a new approach for addressing this environmental challenge.