Influence of characteristics of methanol sorbents salts in mesoporous silica on the performance of adsorption air conditioning cycle

In this paper a new family of methanol sorbents "salts in mesoporous silica" is proposed for utilization in an adsorptive air conditioner driven by a low-temperature heat (T = 338-373 K). The methanol sorption capacity of composites, under typical cooling cycle conditions, was measured by an express method based on the Polanyi principle of temperature invariance. An estimation of the cooling coefficient of performance (COP) was carried out in order to compare the performance of such sorbents with other methanol and water sorbents. Results obtained showed that most of the synthesized composites present methanol sorption ability higher than that of common methanol sorbents (e.g., active carbons). The composite LiCl (30.6 wt %)/SiO2 shows the highest sorption capacity, w(ads) = 0.8 g/g, and uptake variation per cycle, Delta w = 0.71 g/g. The corresponding cooling COP is 0.74 (maximum T-des = 363 K, single-bed cycle), which is comparable to typical COP values for the best water sorbents.