In this work, floc-flotation has been introduced into the elimination of graphene oxide (GO) from water for the first time, so as to reduce its potential risk and biotoxicity. Fourier transform infrared spectroscopy (FTIR) and atomic force microscope (AFM) were used to characterize the prepared GO, and the floc-flotation of GO have been studied both experimentally and theoretically. Extended DLVO theory has been applied to predict the hydrophobic agglomeration of GO, while the effects of dodecylamine hydrochloride (DAH) concentration, pH and stirring strength on the floc-flotation have been discussed. It has been found that the addition of DAH could induce GO surfaces hydrophobic, while appropriate stirring strength provided the kinetic energy for overcoming the energy barrier between the approaching particles. As a result, the hydrophobic agglomeration of GO could be greatly promoted and then the flotation separation of flocs from water could be efficiently realized. This processing could remove up to 98% of the GO nanoparticles form water, resulting in a much less environmental concern for GO in natural water bodies.

在这项工作中，絮凝浮选已被首次引入从水中消除氧化石墨烯（GO），以降低其潜在风险和生物毒性。用傅里叶变换红外光谱（FTIR）和原子力显微镜（AFM）对制备的GO进行表征，并对GO的絮凝进行了实验和理论研究。扩展的DLVO理论已被用于预测GO的疏水团聚，同时讨论了十二烷基胺盐酸盐（DAH）的浓度，pH和搅拌强度对絮凝的影响。已经发现，添加DAH可以诱导GO表面疏水，同时适当的搅拌强度提供了动能来克服接近的颗粒之间的能垒。因此，可以大大促进GO的疏水团聚，从而可以有效地实现絮凝物与水的浮选。该工艺可以去除水中高达98％的GO纳米颗粒，从而减少了天然水体中GO对环境的关注。