A novel metal-organic frameworks based humidity pump for indoor moisture control

Abstract

Latent heat load accounts for a significant proportion of energy consumption by air-conditioning, particularly for buildings in humid climates. Traditional vapor-compression refrigeration dehumidification faces problems like refrigerant leakage, overcooling, and complicated mechanical systems. Here, we report a novel humidity pump that uses metal-organic frameworks (MOFs) as desiccant layers to transport moisture from a low-humidity space to a high-humidity one efficiently. The working principle and operation modes of the humidity pump are introduced herein for which the dehumidification performance is investigated at 22.8 °C with 60% RH. The dehumidification rate and moisture removal efficiency of the MIL-100(Fe) based humidity pump reached 26.24 g h−1 and 0.87 g Wh−1, respectively, and these are 2.15 and 2.12 times higher than that of the humidity pump with silica gel coating. The maximum dehumidification coefficient of performance (DCOP) of the humidity pump could reach up to ~0.46, higher than the conventional desiccant dehumidification systems. In addition, many factors, such as the cycle time, thermoelectric power, air velocity, etc., which may affect the dynamic characteristics and dehumidification performance, were analyzed. Lastly, the localized humidity management ability of the designed humidity pump using MIL-100(Fe) was validated by a small chamber test. The results indicate that the MOF humidity pump could achieve energy-efficient localized moisture control.