The effect of oxidation degree of graphene oxides (GO) on their removal from wastewater via froth flotation was studied in this work. Four types of GO samples with different oxidation degrees were synthesized and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), atomic force spectroscopy (AFM) et al. The effects of cetyl trimethyl ammonium bromide (CTAB) concentration, pH, stirring time on the removal of GO by froth flotation had been discussed. It was found that the addition of CTAB could improve surface hydrophobicity of GO, endowing GO to be easily separated by froth flotation. The removal was dependent on CTAB dosage, pH and stirring time. Moreover, the removal first increased and then decreased with the increasing oxidation degree of GO, and less kinetic energy input was needed to overcome the energy barrier between GO flocs with the increase of oxidation degree. The removal mechanism was proven to be electrostatic attraction, and the different contents of oxgenous-containing functional groups in GOs with various oxidation degrees played a vital role in their removal via froth flotation.

在这项工作中，研究了氧化石墨烯的氧化程度对通过泡沫浮选将其从废水中去除的影响。合成了四种氧化程度不同的GO样品，并通过X射线衍射（XRD），X射线光电子能谱（XPS），透射电子显微镜（TEM），原子力谱（AFM）等进行了表征。讨论了十六烷基三甲基溴化铵（CTAB）的浓度，pH值，搅拌时间对泡沫浮选脱除GO的影响。发现添加CTAB可以改善GO的表面疏水性，使GO易于通过泡沫浮选分离。去除取决于CTAB剂量，pH和搅拌时间。而且，随着GO氧化程度的增加，去除率先增加后减少。随着氧化程度的增加，需要较少的动能输入来克服GO絮凝物之间的能垒。去除机理被证明是静电吸引的，GO中不同氧化度的含氧官能团的不同含量在通过泡沫浮选去除它们中起着至关重要的作用。