Experimental investigation on air dehumidification performance of metal organic frameworks and its application potential for solid desiccant air conditioning systems

In this paper, the air dehumidification performance of MIL-101(Cr) and MIL-101(Cr)-SO3H used for solid desiccant air conditioning (SDAC) system is experimental investigated, and compared with conventional desiccant materials including silica gel, molecular sieve and activated carbon. The results show that the moisture saturated adsorption capacity of MIL-101(Cr) is 1206-1392 mg/g at 25.0-33.5 degrees C/95%RH which is 4-6 times of the conventional adsorbents. MIL-101(Cr) presented an S-shaped isotherm with steep point between 30% and 50%RH which provide the possibility for low temperature regeneration. The water vapor desorption measurement results show that MIL-101(Cr) could have 96.3% (93.5%) desorption rate at 45 degrees C/15.95%RH (45 degrees C/30.60%RH) after saturated adsorption at 33.5 degrees C/58.0%RH. The modified material MIL-101(Cr)-SO3H didn't show better moisture adsorption and desorption performance than MIL-101(Cr) at moderate relative humidity range but higher moisture adsorption capacity at low relative humidity cases. Its saturated adsorption capacity for moisture is 2-3 times of traditional adsorbents. MIL-101(Cr) has shown excellent moisture adsorption capacity and low-temperature regeneration property which makes it be a potential option for SDAC system optimization.