氧化石墨对对硝基苯酚的吸附行为

 以石墨粉为原料，经Hummers 法制备氧化石墨，采用红外光谱、X 射线衍射和扫描电镜对产物结构进行表征。结果表明，氧化石墨含有C-OH、-COOH 和C-O-C 等官能团，使石墨的层间作用力减弱，层间距增大。研究了氧化石墨对对硝基苯酚的吸附行为，当吸附温度为298 K，pH 为7.0 时，氧化石墨对对硝基苯酚的吸附量为80.69 mg/g，是石墨粉吸附量的6.1 倍。吸附热力学研究表明，氧化石墨对对硝基苯酚的吸附可以用Langmuir 方程拟合，吸附是自发的放热过程，低温有利于吸附的进行。动力学拟合显示吸附符合二级动力学模型。

Adsorption Properties of Graphite Oxide for p-Nitrophenol

The graphite oxide was prepared from the powdered graphite via the Hummers method. It was characterized by the methods of the FT-IR, the XRD and the SEM. It is shown that the graphite oxide contains various oxygen-containing functional groups such as C-OH, -COOH and C-O-C, which increase the layer spaces. Adsorption experiments indicate that the graphite oxide has an outstanding adsorption ability for the p-nitrophenol. With the adsorption temperature at 298 K and the pH value at 7.0, the adsorptive capability of the graphite oxide is up to 80.69 mg/g, 6.1 times of that of the graphite powder. From the adsorption isotherms and thermodynamic functions, it is shown that the adsorption can be described by the Langmuir isothermal equation and is a spontaneous and exothermic process. The kinetic study shows that the adsorption can be fitted by second-order dynamic equations.