The gas adsorption isotherm requires accurate measurement for the analysis of porous materials and is used as an index of surface area, pore distribution, and adsorption amount of gas. Basically, adsorption isotherms of porous materials are measured conventionally at 77K and 87K using liquid nitrogen and liquid argon. The cold volume calibration in this conventional method is done simply by splitting a sample cell into two zones (cold and warm volumes) by controlling the level sensor in a Dewar filled with liquid nitrogen or argon. As a result, BET measurement for textural properties is mainly limited to liquefied gases (i.e. N2 or Ar) at atmospheric pressure. In order to independently investigate other gases (e.g. hydrogen isotopes) at cryogenic temperature, a novel temperature control system in the sample cell is required, and consequently cold volume calibration at various temperatures becomes more important. In this study, a cryocooler system is installed in a commercially available BET device to control the sample cell temperature, and the automated cold volume calibration method of temperature variation is introduced. This developed calibration method presents a reliable and reproducible method of cryogenic measurement for hydrogen isotope separation in porous materials, and also provides large flexibility for evaluating various other gases at various temperature.

Abstracts
 1. 서 론
 2. 실험 방법
  2.1 실험 장치의 구성
  2.2 온도와 저온 부피 보정
 3. 결과 및 고찰
 4. 결 론
 References

• 박재우(국립경남과학기술대학교 에너지공학과, 미래융복합연구소) | Jawoo Park (Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology (GNTECH))
• 오현철(국립경남과학기술대학교 에너지공학과, 미래융복합연구소) | Hyunchul Oh (Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology (GNTECH)) Corresponding author