To address the significance of liquid desiccant dehumidification systems, this paper discusses a theoretical model of an air–desiccant contact system. Lithium bromide (LiBr), lithium iodide (LiI), and lithium Chloride (LiCl) were considered as potential aqueous desiccant solution. A cross-flow liquid desiccant dehumidifier with celdek packing materials is considered in the present study. Firstly, this model has been validated for operating values available in the literature. Secondly, this established model has been used to predict the thermodynamic properties such as air humidity, air temperature, desiccant temperature, and solution concentration at various inlet concentrations. The prediction results have shown that the lithium iodide also has the significant potentiality that can make it suitable as a desiccant material in the dehumidification systems. It is found that the LiCl has the more moisture removal capacity to dehumidify the air compared with Lithium iodide (LiI) and lithium bromide (LiBr).