6533b832fe1ef96bd129a20a

RESEARCH PRODUCT

Adsorption and diffusion of linear and dibranched C6 paraffins in a ZSM-5 zeolite

Alain MethivierJ. P. BellatA. DecretteE. JolimaîtreE. LemaireJean-marc Simon

subject

Alkanechemistry.chemical_classificationAdsorptionchemistryDiffusionIsobarOrganic chemistryThermodynamicsIsobaric processMicroporous materialZeoliteIsothermal process

description

The adsorption of n-hexane and 2,2-dimethylbutane on a commercial ZSM-5 zeolite is studied under isothermal and isobaric conditions. ZSM-5 exhibits two different behaviours with linear and dibranched alkanes. A substep at 4 molec.uc−1 is observed on the adsorption isotherm of n-hexane at 348 K. A singular adsorption-desorption process is evidenced on the adsorption isobar at 5.5 kPa with 2,2-dimethylbutane at a temperature close to 343 K when the sample is activated at 298 K under vacuum. The diffusivities have been determined by fitting directly the uptake curves with a numerical resolution of second Fick's law based on finite difference method. Microporous diffusion seems to be rate limiting but surface barrier could also be significant. The diffusivities are almost independent on the filling and are 100 times greater with the linear alkane than with the dibranched one.

yearjournalcountryeditionlanguage
2002-01-01
https://doi.org/10.1016/s0167-2991(02)80326-3