Thermal desorption spectroscopy from high-specific-area solids: hydrocarbon adsorption and diffusion in NaX zeolite crystals

Journal Article · Thu Oct 01 04:00:00 EDT 1981 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(81)90230-X· OSTI ID:5807565

Kiskinova, M; Griffin, G L; Yates, Jr, J T

This work illustrates a novel application of the thermal desorption spectroscopy technique to investigate adsorption, desorption, and surface diffusion phenomena on small zeolite crystals. Ultrahigh-vacuum procedures employed with zeolite samples of very small mass permit measurements to be made without the presence of intergranular diffusion effects. Studies of 1-butene and C/sub 2/H/sub 4/ adsorption have been carried out. A diffusion energy of approx.2.7 kcal/mole has been measured for 1-butene on zeolite-X; for C/sub 2/H/sub 4/ the measured diffusion energy is approx.1.9 kcal/mole. The desorption energy for C/sub 2/H/sub 4/ on zeolite-X is kinetically measured to be 8.9 kcal/mole in excellent agreement with the isosteric heat of adsorption (8.9 kcal/mole). The characteristic behavior of absorbate thermal desorption states upon annealing may be employed to discriminate between species adsorbed on the outer surface of the zeolite crystals, and species which are present within the pores of the zeolite.

• Research Organization: National Bureau of Standards, Washington, DC
• OSTI ID: 5807565
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 71:2; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
033000 -- Natural Gas-- Properties & Composition
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105 -- Separation Procedures
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ACTIVATION ENERGY
ADSORPTION
ALKENES
BUTENES
CATALYSTS
DATA
DESORPTION
DIFFUSION
ENERGY
ETHYLENE
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
KINETICS
MASS SPECTROSCOPY
MATERIALS
MINERALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PERMEABILITY
SORPTION
SORPTIVE PROPERTIES
SPECTROSCOPY
SURFACE PROPERTIES
TEMPERATURE EFFECTS
ULTRAHIGH VACUUM
ZEOLITES