Ammonia sorption on composites ‘CaCl2 in inorganic host matrix’: isosteric chart and its performance

The isosteres of ammonia sorption on new composite sorbents ‘CaCl 2 /γ-Al 2 O 3 ’ and ‘CaCl 2 /vermiculite’ were measured at T = 20–90°C and P = 0.08–9 bar. It was found that the modification of host matrices by the salt dramatically increases the ammonia uptake due to the formation of CaCl 2 × nNH 3 complexes. The isobaric enthalpy and entropy of ammonia sorption by the salt confined to alumina pores were significantly lower than those for the bulk one. For a basic cycle, the values of COP = 0.40–0.48 were calculated at T e = −18°C, T c = 36–42°C and T g = 117–120°C. High COP could make these sorbents promising for application in cooling units driven by relatively low temperature heat. Copyright , Manchester University Press.