Thermodynamic and kinetic aspects of surface acidity. Progress report

Technical Report · Wed Apr 01 00:00:00 EST 1992

DOI:https://doi.org/10.2172/10134554· OSTI ID:10134554

Dumesic, J A

Our research in the general area of acid catalysis involves the characterization of solid acidity and the corresponding assessment of catalytic performance of acidic materials. Acid characterization studies are required to provide essential information about the type of acid site (i.e., Lewis versus Bronsted), the strength of the sites, and the mobility of molecules adsorbed on the acid sites. An accurate measure of acid strength is given by the heat of adsorption of a basic probe molecule on the acid site. A thermodynamic representation of the mobility of adsorbed species on these sites is given by the entropy of adsorption. Important techniques used in these acid site characterization studies include microcalorimetry, thermogravimetric measurements, temperature programmed desorption, infrared spectroscopy and solid state nuclear magnetic resonance. The combination of these acid site characterization studies with reaction kinetics measurements of selected catalytic processes allows the elucidation of possible relationships between surface thermodynamic and kinetic properties of acidic sites. Such relationships are important milestones in formulating effective strategies for the effective utilization of solid acid catalysts. Current work in this direction involves methylamine syntheses over various zeolites, and the basic probe molecules employed include ammonia, methanol, water and mono-, di- and tri-methylamines. 31 refs., 18 figs., 1 tab.

• Research Organization: Univ. of Wisconsin, Madison, WI (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-84ER13183
• OSTI ID: 10134554
• Report Number(s): DOE/ER/13183-T1; ON: DE92011194
• Resource Relation: Other Information: PBD: [1992]
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ZEOLITES
CATALYTIC EFFECTS
METHYLAMINE
CHEMICAL PREPARATION
MOLECULES
MOBILITY
DEUTERIUM
NUCLEAR MAGNETIC RESONANCE
NITRIC OXIDE
REDUCTION
PROGRESS REPORT
LEWIS ACIDS
BROENSTED ACIDS
ADSORPTION HEAT
ENTROPY
CALORIMETRY
THERMAL GRAVIMETRIC ANALYSIS
INFRARED SPECTRA
DESORPTION
CHEMICAL REACTION KINETICS
400201
CHEMICAL AND PHYSICOCHEMICAL PROPERTIES