Preparation and characterization of aminated graphite oxide for CO2 capture

Adsorption with solid sorbents is one of the most promising options for postcombustion carbon dioxide (CO2) capture. In this study, aminated graphite oxide used for CO2 adsorption was synthesized, based on the intercalation reaction of graphite oxide (GO) with amines, including ethylenediamine (EDA), diethylenetriamine (DETA) and triethylene tetramine (TETA). The structural information, surface chemistry and thermal behavior of the adsorbent samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy (IR), transmission electron microscope (TEM), elemental analysis, particle size analysis, nitrogen adsorption as well as differential thermal and thermogravimetric analysis (DSC-TGA). CO2 capture was investigated by dynamic adsorption experiments with N-2-CO2 mixed gases at 30 degrees C. The three kinds of graphite oxide samples modified by excess EDA, DETA and TETA showed similar adsorption behaviors seen from their breakthrough curves. Among them, the sample aminated by EDA exhibited the highest adsorption capacity with the longest breakthrough time of CO2. Before saturation, its adsorption capacity was up to 53.62 mg CO2/g sample. In addition, graphite oxide samples modified by different amount of EDA (EDA/GO raw ratio 10 wt%, 50 wt% and 100 wt%) were prepared in the ethanol. Their CO2 adsorption performance was investigated. The experimental results demonstrated that graphite oxide with 50 wt% EDA had the largest adsorption capacity 46.55 mg CO2/g sample. (C) 2011 Elsevier B.V. All rights reserved.