Evaluation of the performance of solid sorption refrigeration systems using carbon dioxide as refrigerant

The refrigerant–adsorbent pairs at present mostly used in research on solid-sorption refrigeration cycles are ammonia–carbon, methanol–carbon, water–silica gel and water–zeolite. Porosity tests have been carried out on an alternative, carbon dioxide, as refrigerant with several types of carbon, zeolite and silica gel as adsorbent. The results of fitting to the Dubinin equation and modelling of cycles based on these pairs are presented. Due to its low latent heat, the performance of adsorption refrigeration systems using CO2 as refrigerant is poor. However, carbon dioxide may be useful where the toxicity and incompatibility of ammonia and copper is valued.