The Application of Adsorption to Remove Aromatic Hydrocarbons from Flue Gas

Aromatic hydrocarbons recommended as the persistent organic pollutants distribute widely in atmospheric environment. PAHs (polycyclic aromatic hydrocarbons) and BTEX (benzene, toluene, ethyl benzene and p-xylene) are harmful to the environment and health of people, since they are the precursors of photochemical oxidants and agents of the acid rain, and have high degree of mutagenicity and carcinogenicity. Among the purifying technology for flue gas, adsorption is a relatively promising approach to remove aromatic hydrocarbons from flue gas as its advantages of high removal efficiency, low consumption and easy using. The recent studies on choice of sorbents, influence factors, parameters estimation and modeling of aromatic hydrocarbons are reviewed in this paper. By comparing the adsorption properties of different sorbents for aromatic compounds, structure and polarity of sorbents are the two main factors considered in choice of sorbents. The effects of textural properties, surface chemistry and other impact factors, such as interaction between adsorbates, physicochemical properties of adsorbates, operating conditions, on aromatic hydrocarbons adsorption behavior are analyzed.