Removal of methyl-ethyl ketone vapour on polyacrylonitrile-derived carbon/mesoporous silica nanocomposite adsorbents

Mesoporous silica supports (MCM-41, SBA-15 and silica gel) were modified by the introduction of controlled amounts of polymer-derived carbon. Precipitation polymerization of polyacrylonitrile in the aqueous suspension of a silica material was used as a deposition method. The samples of PAN/silica composites were studied by thermal analysis, performed in air and inert atmosphere, in order to determine the amount of a deposited polymer and its thermal stability. The effect of surface area of a silica support and the monomer concentration in the mother solution on the effectiveness of deposition was revealed. The PAN/silica composites were transformed into C/SiO2 adsorbents by carbonization carried out at 623 K. Texture (low-temperature sorption of N-2), surface structure (FTIR-DRIFT) and morphology (SEM) of the carbonized samples were investigated. The adsorption tests in the elimination of methyl ethyl ketone from gas phase were performed under dynamic conditions. The MCM-41-based composites containing highly dispersed carbon layers on the surface appeared to be the most promising adsorbents for a commercial application. Moreover, these materials exhibited a high stability in the adsorption desorption runs repeated ten times suggesting the possibility of regeneration of the adsorbent bed without a significant loss in the adsorption effectiveness. (C) 2011 Elsevier Inc. All rights reserved.