Calcium ion-exchanged zeolite 13X: Properties measurement and potential usage in solar adsorption cooling systems

Abstract

Ca-ion exchanged zeolites were synthesized from zeolite 13X and calcium chloride in this study. XRF, TGA and BET were used to measure the adsorption related properties of the Ca-ion-exchanged zeolites. The influence of the synthesis conditions of the zeolites and the potential usage of them in solar adsorption cooling systems were investigated. 0.27g/g of difference in equilibrium water uptake between two operation conditions was recorded, which has 17.8% improvement compared with pure zeolite 13X. Ideal Coefficients of Performance (COP) and Specific Cooling Power (SCP) for an adsorption cooling system using the Ca-ion-exchanged zeolites were also estimated. The increase of ideal COP was not much, 2.4%, but the improvement of the actual COP was predicted to be up to 70% by reducing the large unwanted energy loss generally experienced in actual systems. The ideal SCP was also found to be 504 W/kg, increased by 22.2%. This suggests that this Ca-ion-exchanged zeolite can be used in solar adsorption cooling system with much better performance than zeolite 13X. © Springer-Verlag Berlin Heidelberg 2012.