Adsorption characteristics of ethanol onto promising adsorbents for adsorption cooling applications.

Adsorption characteristics of ethanol onto three promising adsorbents have been investigated for developing high performance adsorption chillers. Adsorbents used in the present study are (i) parent Maxsorb III, (ii) two adsorbents based on spherical phenol resin treated with different mass ratios of KOH named as KOH4-PR and KOH6-PR. Adsorption equilibrium and kinetics of the assorted pairs have been measured using magnetic suspension adsorption measurement unit. The Dubinin-Astakhov (D-A) and Dubinin–Radushkevich (D-R) equations are used to fit adsorption isotherms whilst adsorption kinetics is presented by Fickian diffusion model. The pressure-temperature-concentration diagrams of the studied adsorbents have also been presented. Experimental results show that the adsorption equilibrium capacities of KOH6-PR/ethanol, KOH4-PR/ethanol and Maxsorb III/ethanol pairs are 2, 1.43 and 1.2 kg kg-1, respectively. The diffusion time constant of KOH4-PR is found to be higher than that of other studied adsorbents especially at the lower range of adsorption temperatures.