Performance comparison of sorption compressors for methane using metal-organic frameworks and activated carbon as adsorbents

Abstract

Many optical devices can benefit from cryogenic cooling; however, the resolution of these devices suffers from microvibration from mechanical cryocoolers. Unlike mechanical cryocoolers, sorption cryocoolers do not have any active moving parts and are essentially vibration-free. Sorption cryocoolers are thermally driven and their performance is highly determined by the properties of the adsorbents employed in the compressors. In this study, the thermodynamic and dynamic modelling of sorption compressors adopting Saran activated carbon, MOF-5 and HKUST-1 metal–organic frameworks as adsorbents are conducted to find suitable adsorbents to realize efficient compression. It is found that a sorption compressor with MOF-5 as the adsorbent has the worst performance. Saran carbon has the highest mass-flow rate. And whether HKUST-1 or Saran carbon has higher efficiency depends on the operating conditions. The effects of heat sink temperature and heater power on the performance of sorption compressors are also investigated. The analysis method can be employed to choose suitable sorbent materials and operating conditions when designing sorption compressors.