Adsorption of organic vapour pollutants on activated carbon

Emissions of organic vapor pollutants, arising mainly from anthropogenic sources have major environmental impact and the low emission levels required by increasingly stringent legislation are difficult to achieve. Adsorption on activated carbon can be used as a final stage for removal of very low concentrations of volatile organic pollutants present in air and gas streams. Isotherms and adsorption kinetics for a range of carbons with different porous structures and volatile organic compounds (VOCs) with a range of properties provide an improved understanding of the relationship between pore structure, adsorptive properties and adsorption characteristics. Competitive adsorption of other species present in gas flows, in particular water vapor, reduces adsorption capacity and kinetics. Laboratory measurements, which simulate process conditions, for example, very low vapor pressure, high temperature and competitive adsorption; provide an insight into the mechanisms associated with adsorption processes allowing process optimization.