A linear comprehensive adsorption model of hydrogen on super activated carbon under supercritical conditions

The adsorption isotherms of hydrogen on super activated carbon were measured systematically, covering a temperature range of 93-293 K at 20 K intervals and pressures up to 7 MPa. All the experimental data were linearized by adopting the coordinates In ln(n) vs 1/(ln P). The results indicate that the adsorption limit (P-lim, n(lim)) exists virtually at high pressure and has a certain physical meaning. Based on the adsorption limit, further analyses were carried out by modeling the adsorption isotherms in the coordinates ln(n(lim)/n) vs In(RT(ln(P-lim/P) and a linear comprehensive adsorption model was proposed in the form n(lim) = n (.) exp (psi/T + lambda\T - c\)(beta .) [RTln(P-lim/P)](b) which can predict the adsorption isotherm of hydrogen on activated carbon in supercritical conditions. (C) 2002 Elsevier Science (USA).