Al2O3-Cact-(CuO, Cr2O3, Co3O4) Adsorbents-Catalysts: Preparation and Characterization

Abstract

Al₂O₃-C_act-(CuO, Cr₂O₃ Co₃O₄) adsorbents-catalysts were prepared using Al₂O₃-C_act (alumina gel–activated carbon) adsorbent and different amount of CuO, Cr₂O₃ and Co₃O₄. The active components were incorporated into wet alumina gel–carbon mixture using different conditions (by sol-gel method and mixing a milled metal oxides). Equilibrium adsorptive capacity measurements of alcohol vapours were carried out in order to determine the influence of preparation conditions on the stability of prepared adsorbents–catalysts. Specific surface area of the prepared adsorbents-catalysts were measured by BET method. It was established that for adsorbent-catalyst produced by sol-gel method S_BET = 244.7 m²/g. Surface area S_BET = 29.32 m²/g was obtained for adsorbent-catalyst with metal oxides. On the basis of these results it was assumed that active carbon was lost in this adsorbent-catalyst during the preparation process. Sol-gel derived adsorbent–catalyst was tested for the oxidation of methanol vapours. Catalytic oxidation was carried out in fixed-bed reactor. Experimental data indicate that adsorptive capacity of the adsorbent–catalyst is (3.232 – 3.259) mg/m³ CH₃OH at relative air humidity is 40 % – 50 %. During a fast heating of CH₃OH – saturated adsorbent-catalyst a part of adsorbate is converted to CO₂ and H₂O. Methanol conversion increases with increasing of adsorbent-catalyst heating rate.

DOI: http://dx.doi.org/10.5755/j01.ms.19.1.3832