Adsorption calorimetry in supported catalyst characterization: Adsorption structure sensitivity on Pt/-gamma-Al2O3

Date

2005-08-15

Author

Üner, Deniz

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

161
views

0
downloads

In this study, the structure sensitivity of hydrogen, oxygen and carbon monoxide adsorption was investigated by changing the metal particle size of Pt/Al2O3 catalysts. The 2% Pt/Al2O3 catalysts were prepared by incipient wetness method; the particle size of the catalysts was modified by calcining at different temperatures. The differential heats of adsorption of hydrogen, carbon monoxide and oxygen were measured using a SETARAM C80 Tian-Calvet calorimeter. Hydrogen chemisorption sites with low and intermediate heats were lost when the particle size increased consistent with the previous reports in the literature. No structure dependency was observed for hydrogen, carbon monoxide or oxygen initial heats of adsorption. The adsorbate:total metal stoichiometries at saturation systematically decreased with increasing particle size. While the hydrogen site energy distribution changed with increasing particle size, oxygen and carbon monoxide adsorption site energy distributions did not change appreciably with the metal particle size.

Subject Keywords

Physical and Theoretical Chemistry, Instrumentation, Condensed Matter Physics

URI

https://hdl.handle.net/11511/41620

Journal

THERMOCHIMICA ACTA

DOI

https://doi.org/10.1016/j.tca.2005.01.058

Collections

Department of Chemical Engineering, Article

Suggestions

OpenMETU
Core

Adsorption calorimetry in supported catalyst characterization : adsorption structure sensitivity on pt(y-Al2o3 Üner, Murat; Üner, Deniz; Department of Chemical Engineering (2004) In this study, the structure sensitivity of hydrogen, oxygen and carbon monoxide adsorption was investigated by changing the metal particle size of Pt/Al2O3 catalysts. 2 % Pt/Al2O3 catalysts were prepared by incipient wetness method; the particle size of the catalysts was manipulated by calcining at different temperatures. The dispersion values for the catalysts calcined in air at 683K, 773K and 823K were measured as 0.62, 0.20 and 0.03 respectively. The differential heats of adsorption of hydrogen, carbon ...
Resveratrol and its analogues resveratrol-dihydroxyl isomers: semi-empirical SCF-MO calculations Erkoç, Şakir; Keskin, N; Erkoc, F (Elsevier BV, 2003-08-01) The structural and electronic properties of resveratrol and its three analogues resveratrol-dihydroxyl isomers have been investigated theoretically by performing semi-empirical self-consistent field molecular orbital theory calculations. The geometry of the systems have been optimized and the electronic properties have been calculated at the level of AMI method.
DSC study of the combustion properties of turkish coals Ozbas, K.E.; Kök, Mustafa Verşan; Hicyilmaz, C. (Springer Science and Business Media LLC, 2003-01-01) In this research, differential scanning calorimetry (DSC) was used to determine the combustion behavior and kinetic analysis of raw and cleaned coal samples of different size fractions. DSC curves of the three coal samples (Soma, Tuncbilek and Afsin Elbistan) showed two reaction regions. The first reaction region was due to moisture loss (endothermic) and observed in the temperature range of ambient to 150°C. The second region was the exothermic region due to the combustion and observed in the temperature r...
Quantum chemical investigation of thalidomide molecule Erkoç, Şakir; Erkoc, F (Elsevier BV, 2005-04-14) The structural and electronic properties of the thalidomide molecule have been investigated theoretically by performing semi-empirical molecular orbital (AM1) and density functional theory calculations. The geometry of the molecule has been optimized by AM1 method and the electronic properties of the molecule have been calculated by density functional theory in its ground state.
Certain endohedrally hydrogen doped Be@C-60 systems - A theoretical study Türker, Burhan Lemi (Elsevier BV, 2002-01-31) Endohedrally various numbers (n = 1-5) of hydrogen molecules doped Be@C-60 systems, (Be + nH(2))@C-60 are considered for semiempirical molecular orbital treatment at the level of AM1(RHF) method to investigate the possible usage of these, yet nonexistent, structures as hydrogen storage media. The calculations revealed that in the case of n = 5, one of the hydrogen molecules undergoes a kind of hydridic interaction with Be atom to form quasi BeH2 structure.

Citation Formats

D. Üner, “Adsorption calorimetry in supported catalyst characterization: Adsorption structure sensitivity on Pt/-gamma-Al2O3,” THERMOCHIMICA ACTA, pp. 107–112, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41620.