OPTIMIZATION OF THE TEXTURAL CHARACTERISTICS OF AN ALUMINA TO CAPTURECONTAMINANTS IN NATURAL-GAS

Capillary condensation of water can seriously impair the performance o f an adsorbent intended for use in removing contaminants (mercury, ars enic, sulfur, etc.) in natural gas. Adsorption and desorption isotherm s were used to determine how the nature and pore structure distributio n of the adsorbent (alumina, active cabon) affect water adsorption. Th e contribution of the different phenomena involved (chemisorption, phy sisorption, capillary condensation) have been determined. The threshol d of capillary condensation is reached much more rapidly on active car bon and microporous alumina (40% relative humidity) than on a highly m esoporous alumina (75-80% relative humidity).