LAUSR

In the present paper, the capabilities of canola meal (CM)-based biosorbents for the selective water removal from aqueous solution of butanol were investigated for purifying butanol. The raw canola meal (RCM) after protein extraction was pretreated using 5% (v/v) sulfuric acid to enhance the water adsorption characteristics of CM. This pretreated canola meal (PCM) was used as an adsorbent along with the RCM adsorbent for selective water removal. Biosorbents were characterized by Fourier transform infrared, carbon hydrogen nitrogen sulfur (CHNS), Brunauer, Emmett, and Teller surface area, and X-ray diffraction. The surface area and micropore volume were increased in PCM. In addition, crystallinity index and CHNS content in PCM were also increased. Both the adsorbents were able to selectively adsorb water from the aqueous solutions of butanol. PCM demonstrated a higher water uptake and a higher final butanol concentration than RCM. The adsorption diffusion model better fits the kinetic data of water adsorption by PCM in a butanol solution containing 95.3 wt% water. The adsorption isotherm was also investigated. The mean free energy per molecule of adsorbate () based on Dubinin–Radushkevich theory indicated that water adsorption is favorable and water or butanol adsorption was physical in nature.