The vapor pressure of desiccants solution has great impact on the performance of the liquid desiccant air-conditioning system. Calcium chloride is the cheapest and most readily available desiccant

but it has the disadvantage of higher vapor pressure

lithium chloride is the most stable desiccant

but its cost is relatively high. To stabilize calcium chloride and to decrease the high cost of lithium chloride

the two can be mixed in different weight combinations. In this research

the vapor pressure of some desiccants

such as calcium chloride

lithium chloride

and the mixture of calcium chloride and lithium chloride was analyzed and calculated using the classical thermodynamics approach. The calculated values agree well with the experimental data. This method can be used to predict vapor pressure of the new desiccants and offer a theoretical basis to choose liquid desiccants in the design of liquid desiccant air-conditioning system.