Activated carbons are excellent adsorbents for removing very low concentrations of volatile organic vapor pollutants. Comparisons of porous materials based on standard measurements, such as nitrogen adsorption, provide only limited information and may be misleading. Adsorption isotherms and kinetics for specific organic vapor pollutants are important for assessing the suitability of activated carbons for given applications. Laboratory measurements should be carried out under conditions that simulate process conditions, for example, in the case of dioxin removal from flue gases, these are very low vapor partial pressures and high temperatures. Multi-component streams are a very complex scenario but binary systems can be studied by micro-gravimetry combined with dynamic sampling mass spectrometry. Results have shown that competitive adsorption is a major issue since it slows the adsorption kinetics and species may be displaced from the surface, increasing the complexity of associated studies.

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