Abstract:
In order to evaluate the performance of activated carbon adsorption and desorption of benzene series, taking the commercial honeycomb activated carbon as the adsorption material, the specific surface area, aperture distribution and surface pore structure morphology of the activated carbon were analyzed by nitrogen adsorption isotherm and scanning electron microscope. The effects of benzene concentration, benzene flow and benzene species flowing through honeycomb activated carbon on their adsorption capacity were evaluated by dynamic adsorption evaluation device and gas chromatography system. The desorption temperature curve of honeycomb activated carbon was also studied by temperature programmed technology. At the same time, the effects of water vapor on honeycomb activated carbon adsorption capacity and desorption temperature curve were investigated. The results showed that the unit saturation adsorption capacity of honeycomb activated carbon to benzene species followed the sequence of xylene > toluene > benzene, with the values varied from 66.5 to 138.1 mg/g. The reason for different adsorption capacities maybe due to the molecular size effect of benzene species. The optimal desorption temperature of benzene species was basically maintained at 175 ºC. The competitive adsorption effect of water vapor could significantly inhibit the unit saturation adsorption capacity of benzene, which was reduced by 36.3% after the introduction of 1.8% water vapor, as the adsorption sites were partly occupied of by water vapor, significantly reducing the adsorption capacity of benzene.