Mass transfer performance of two commonly used liquid desiccants: LiBr aqueous solution and LiCl aqueous solution was compared at the same solution temperature and surface vapor pressure. The heat capacities of the two desiccants were about the same at the same volumetric flow rate

while LiBr solution had a higher density and a smaller specific heat capacity. The key factors influencing performance were heat capacity ratio of air to desiccant and mass transfer unit

according to the analysis of the analytical solutions of heat and mass transfer processes. The change of mass transfer coefficient with air and desiccant inlet parameters was derived based on the experimental results. The mass transfer performance of LiBr solution was a little better than that of LiCl solution at the same desiccant volumetric flow rate within the experimental operating range.