Development of a new synthesized adsorbent for refrigeration and air conditioning applications

This paper presents the results of a study concerned with the impregnation of microporous silica gel, as host matrix, with the calcium chloride, as hygroscopic salt promoter. The concentration of the aqueous solution of calcium used in the preparation of the samples was varied from 0% up to the limit of solubility of CaCl2 in the water. At high humidity, the composite adsorbents obtained with the solutions at concentration greater or equal to 40% have been tested to yield a maximum capacity of adsorption approximately doubling their own weight and quadrupling that of the pure silica gel. Likewise, they were found to be desorbing faster compared to the substrate silica gel. The impact of these improved sorption properties on the performance of an adsorption air conditioning system was simulated. The results show a significant increase of the specific cooling power (SCP) and, consequently, a drastic reduction of the quantity of adsorbent needed to reach an intended target cooling power.