Factors affecting the adsorption of gaseous environmental odors by activated carbon: A critical review

Activated carbon has a long history of application to abate gaseous environmental odors; however, design and operating decisions are primarily based on empirical relations and pilot testing, with limited use of fundamental mechanistic knowledge. To support improved abatement outcomes, environmental odorant adsorption was reviewed. While influenced by a range of adsorbate and adsorbent properties and process operating conditions, information about their impacts is often limited or unavailable. Current research has focused on volatile sulfur compounds, with lesser focus on volatile organic compounds and volatile nitrogen compounds. Even within volatile sulfur compounds, most work has focused on hydrogen sulfide and the full range of reduced sulfur compounds (important environmental odorants) remain to be studied. The current narrow window of knowledge does not reflect the complexity of environmental odorants and is limiting development and systematic application of this technology. It has been demonstrated that single component adsorbent characterization does not reflect the adsorption of the complex mixture of odorants and non-odorous compounds that make up environmental odor emissions. Studies to explore adsorption competition in multi-compound systems and develop methods/guidance to account for this in abatement system selection and design are required to achieve cost effective and reliable outcomes.