Nonisothermal adsorption of water by synthetic NaX zeolite pellets

✍ Scribed by K. Abdallah; Ph. Grenier; L.M. Sun; F. Meunier

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 989 KB
• Volume: 43
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(88)80007-1

✦ Synopsis

Experimental measurements and theoretical analysis of the uptake and surface temperature are presented for adsorption of water by synthetic NaX zeolite pellets of diffcrcnt sizes. It is shown that. under the present experimental conditions, the heat dissipation effect piays a dominant role in the adsorptlon kinetics, after a short initial stage which is controlled essentially by both the macropore diffusion and the micropore diffusion. An excellent agreement is obtained between the experimental data and thcoreticat results given by a nonisothermal model for a bidisperse structure, both for the uptake and for the surface temperature curves. The values of diffusivities determined by the curve-fitting method over an initial stage are of the order of D, -3 x 10d5 mz;s for the macropore diffusion and D,,,/R: -0.003 s-' for the micropore diflusion, and these values exhibit an independence of the pellet size for all the tested pellets. Furthermore, it is demonstrated that the use of an effective model for the monodisperse structure ma! also give a good agreement, but the values of diffusivities determined by the best fit are not very meaningful because of their dependence on the pellet size.