Sircar, M. B. Rao and T. C. Golden

The chemical nature of the sites of alumina for water adsorption is not clearly understood. Chemisorption of water through dissociation into H and 0H ions which attach to the alumina surface, hydrogen bonding of water with surface oxygen and hydroxyl groups, van der Waals and pole-pole interactions between the water molecule and the alumina surface as well as condensation of water vapour in the mesopores of alumina are possible mechanisms [5]. 

Manufacturer Alcoa Alcoa Alcan Rhone-Poulenc Kaiser Laporte 

ADSORPTION OF WATER VAPOUR FROM GAS STREAMS ON ACTIVATED ALUMINAS 

The difference in the pore structure and surface chemistry of different activated aluminas is manifested by significantly different characteristics for adsorption of water vapour as pure gas or from gas mixtures. These properties are illustrated below. 

Empirical adsorption equilibrium models like Langmuir and Freundlich can generally be used to describe type I pure water vapour adsorption isotherms on aluminas [6]  

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