氧化石墨烯/豆腐复合材料吸附亚甲基蓝的研究

Studies of the Adsorption Properties of Methylene Blue onto GO/Soybean Curd Composites

利用改性hummers法制备了氧化石墨烯(GO),然后将其与热豆浆按一定比例混合,并加入适量固化剂(葡萄糖酸内酯)形成氧化石墨烯/豆腐,再通过冷冻干燥制成了疏松多孔的氧化石墨烯/豆腐复合物(GOT)。采用扫描电子显微镜和傅里叶变换红外光谱仪对GOT的形态和物理化学性质进行了表征,并通过一系列实验研究了GO含量、溶液pH、吸附剂加入量、接触时间和温度等因素对GOT吸附亚甲基蓝(MB)的影响。实验结果表明,GOT能够有效吸附溶液中的MB,平衡吸附数据符合Langmuir模型;吸附动力学研究显示准二级动力学模型能更准确的描述GOT对MB的吸附数据;热力学参数则说明该吸附是一个吸热和自发的过程。

Graphene oxide (GO) was prepared by the method of hummers, which was mixed with hot soybean milk according to a certain proportion, then adding an appropriate amount of curing agent (glu-conolactone) into the mixture to form the graphene oxide/tofu. After freeze-drying, the loose and porous graphene oxide/tofu complex (GOT) was prepared. The morphology and physicochemical properties of GOT were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FT-IR). A series of experiments were carried out to research the effects of the content of GO, pH, amount of adsorbent, contact time and temperature on the adsorption of methylene blue (MB) on GOT. The experimental results showed that GOT can effectively adsorb MB in solution and the equilibrium adsorption data were well fitted to the Langmuir model. The adsorption kinetic study revealed that the pseudo-second-order model can accurately describe the adsorption data of GOT to MB better and the thermodynamic parameters indicated that the adsorption was an endothermic and spontaneous process.