Automated determination of high-temperature and high-pressure gas adsorption isotherms using a magnetic suspension balance

• Published in: Measurement science & technology Vol. 10; no. 2; pp. 117 - 126
• Main Authors: Weireld, G De, Frère, M, Jadot, R
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.02.1999; Institute of Physics
• Subjects: Exact sciences and technology; Experimental studies of gravity; General relativity and gravitation; Mass and density; Measurements common to several branches of physics and astronomy; Metrology, measurements and laboratory procedures; Physics; Gravimetric analysis; Purification; Mass measurement; Adsorption isotherms; High temperature; Experimental study; High pressure; Magnetic suspension
• ISSN: 0957-0233; 1361-6501
• DOI: 10.1088/0957-0233/10/2/010

A gravimetric experimental device allowing the measurement of pure gas adsorption isotherms is presented. The mass measurement is performed by a Rubotherm magnetic suspension balance instrumented to allow automated adsorption isotherm measurements for pressures ranging from 0 to 10,000 kPa and for temperatures from 303 to 423 K. Its main originality is that, although it works at high temperature, all the components in contact with the adsorbate are at the experimental temperature so that it is possible to study adsorbates which condensate at high pressure and ambient temperature. As examples of experimental results, adsorption isotherms of nitrogen and butane on activated carbon at five temperatures (303, 323, 343, 363 and 383 K) are presented. The 303 K nitrogen adsorption isotherm is compared to data obtained for the same system with a volumetric apparatus. (Original abstract - amended)