He and Ar sorption on arc-produced cathode deposit consisting of multiwalled carbon nanotubes—graphitic and diamond-like carbon

H 2 , He and Ar sorption characteristics in a mixture of multiwalled carbon nanotubes (MWCNT), graphite and diamond-like carbon produced as a cathode deposit during the Kratscmer Hoffman arc process were investigated. A dynamic technique was used to determine the adsorption equilibrium parameters in a temperature range of 30–200 °C. Adsorption equilibrium constants were evaluated using the moment analysis of the chromatographic peaks. At 30 °C, the adsorption equilibrium constant of H 2 on the MWCNT cathode deposit was found to be 8.91 × 10 - 4 m 3 kg - 1 , whereas it has value of 5.65 × 10 - 4 at 200 °C. Heats of adsorption of H 2 , He and Ar on the MWCNT cathode deposit were determined as - 2.89 , - 2.94 and - 3.01 kJ mol - 1 , respectively. The values of heat of adsorption obtained indicated weaker interactions of gases, implying physical adsorption of H 2 , He and Ar on the MWCNT cathode deposit used.