活化氧化石墨烯的制备及对甲基橙的吸附

为了提高氧化石墨烯(GO)的比表面积和吸附性能,采用氢氧化钾对GO进行高温固相活化,制备出活化氧化石墨烯(GOKOH),并将其用于对水中阴离子染料甲基橙(MO)的吸附研究。结果表明,GOKOH的比表面积可达672.48 m2/g。GOKOH能在较宽的p H范围内实现对MO的高效去除,去除率高达94.87%,吸附平衡时间约为150 min。准一级和准二级动力学拟合的理论平衡吸附容量分别为549.87 mg/g和549.45 mg/g,Langmuir模型的饱和吸附容量为632.91 mg/g。该吸附过程受边界层扩散与颗粒内扩散两个步骤控制,符合二级动力学模型和Langmuir模型,并主要以化学吸附为主。

Preparation of activated graphene oxide and its adsorption for methIy orange

In order to improve the specific surface area and adsorption capacity of graphene oxide (GO),GOKOH has been synthesized with KOH by high temperature solid state activation,and it is used for the research on its adsorption for anionic dye methyl orange (MO) in water. The results show that the specific surface area of activated GOKOH can reach 672.48 m2/g. GOKOH can effectively remove MO in a wide range of pH and the MO removing rate is as high as 94.87%,and the time of adsorption equilibrium is 150 min. The pseudo first order kinetics and pseudo second order kinetics fitted theoretical equilibrium adsorption capacities are 549.87 mg/g and 549.45 mg/g , respectively,and the saturated adsorption capacity of Langmuir model is 632.91 mg/g. The adsorption process is controlled by two different steps:boundary layer diffusion and inside particle diffusion. It is in line with the 2nd level dynamics model and Langmuir model,and it is mainly chemical adsorption.