Experimental investigation on activated carbon-ethanol pair for solar powered adsorption cooling applications

Abstract

Adsorption equilibrium uptake of ethanol onto a highly porous activated carbon based adsorbent, namely Maxsorb III, has been experimentally investigated using a thermo-gravimetric analyzer (TGA) unit over adsorption temperatures ranging from 20 to 60 °C. The Dubinin-Astakhov (D-A) equation has been used to correlate the experimental data. Isosteric heat of adsorption is also estimated by using the Clausius-Clapeyron equation. Employing a thermodynamically equilibrium model, the performance of the ideal adsorption cooling cycle has also been studied and compared to that of activated carbon fiber (ACF)-ethanol pair. Experimental results show that Maxsorb III can adsorb up to 1.2 kg of ethanol per kilogram of adsorbent. Theoretical calculations show that, the Maxsorb III-ethanol adsorption cycle can achieve a specific cooling effect of about 420 kJ kg-1 at an evaporator temperature of 7 °C along with a heat source of temperature 80 °C and thus the pair is recommended for solar cooling applications. © 2008 Elsevier Ltd and IIR.