Composite Sorbent of Methanol Lithium Chloride in Mesoporous Silica Gel for Adsorption Cooling Machines: Performance and Stability Evaluation

In this paper, a novel composite sorbent of methanol "lithium chloride in mesoporous silica gel" is proposed for adsorption cooling machines. Methanol sorption isotherms were measured by a thermogravimetric technique. This composite demonstrated outstanding methanol sorption ability (up to 0.6 g of methanol per 1 g of dry sorbent). The thermodynamic coefficient of performance (COP), calculated by mathematical modeling for a basic cooling cycle, can reach 0.72 at desorption temperature of 343 K. The real performance was measured by testing this novel material in a lab-scale adsorption chiller. The specific cooling power of 210-290 W/kg and real cooling COP of 0.32-0.4 were obtained. Cycling stability of the sorbent was successfully verified, Such results indicate that the new composite sorbent "lithium chloride in mesoporous silica gel" can be recommended for application in adsorption cooling machines driven by low temperature heat.