Modification of the adsorption properties of alumina by the addition of a water soluble polymer

Abstract

Pure aluminas and polymer-containing alumina samples have been calcined in the temperature range 150-850°C. The adsorption of nitrogen at - 196°C and of cyclohexane, benzene, methanol and water vapour at 35°C has been measured on some of these samples. At lower calcination temperatures, the polymer additive, polyvinyl pyrrolidone, decreases the surface area and the mean pore radius. At higher calcination temperatures, the polymer additive significantly increases the total pore volume and the pore size. It is proposed that the polymer additives may be decreasing the surface polarity of alumina and consequently lowering the adsorption capacity for polar adsorbates.