Removal of benzene and methyl ethyl ketone vapor: Comparison of hypercrosslinked polymeric adsorbent with activated carbon

A novel hypercrosslinked polymeric adsorbent (HY-1) with high surface area and specific bimodal pore size distribution in the regions of micropore (0.5-2.0 nm) and meso-macropore (30-70 nm) was prepared. Adsorption properties of benzene and methyl ethyl ketone (MEK) vapors onto HY-1 were investigated and compared with a commercial microporous activated carbon (m-GAC). The equilibrium adsorption data showed that the adsorption capacities of benzene and MEK on HY-1 were larger than those of m-GAC at the higher relative pressure. The Dubinin-Radushkevich (D-R) equation was found to fit the experimental data well. The isosteric enthalpy of adsorption for benzene and MEK were calculated. The m-GAC exhibited much higher values of Delta H-st for the VOCs than HY-1 at the whole loading studied, which can lead to significant temperature rises during the adsorption step. The results of dynamic experiments revealed that HY-1 had a good dynamic adsorption capacity with a longer breakthrough time and shorter length of mass transfer zone due to its specific bimodal property. Therefore, HY-1 will be a particularly efficient and competitive adsorbent for VOCs recovery, especially at medium-high concentrations. (C) 2011 Elsevier B.V. All rights reserved.