Characterizing the Hydrophobic Properties of Activated Carbon and the Factors Affecting VOC Adsorption

Regeneration is vital to the life cycle of adsorbents such as activated carbon. Regeneration losses, in the forms of adsorbent mass and adsorption capacity, have long plagued the life-cycle of conventional adsorbents. Adsorption losses are compounded by the presence of moisture in exhaust gas streams during VOC treatment, due to the competition for adsorbent sites between water and VOCs. Since water vapor often out-competes the VOCs for these sites, the carbon's loss of adsorption capacity can be attributed to water's affinity to the carbon surface. The present research explores the hypothesis that selective organic phase adsorbents can be produced by designing the substrate material such that it exhibits hydrophobicity and selectivity for organic vapors. At the time of writing, this study is still in the design phase. An on-line apparatus, currently being developed for lab-scale use, is theorized for the continuous measurement of VOC concentrations under varying relative humidity conditions. This work aims to advance adsorption science for environmental applications, as it has the potential to provide a new class of gas phase adsorbents, advance polymer composite adsorbent manufacturing methods, and develop a novel adsorbent design approach using ground-up methodology rather than an empirical approach. Two additional research projects, to which the author provided support, are also described in brief.