Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Catalysis letters 12 (1992), S. 73-86 
    ISSN: 1572-879X
    Schlagwort(e): Silica supported Pd catalyst ; catalyst particle size ; CO chemisorption ; H2 chemisorption ; Pd dispersion ; transmission electron microscopy ; in-situ UV reflectance spectroscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The effect of pretreatment on the dispersion of Pd catalysts supported on silica has been studied. The catalysts were prepared from [Pd(NH3)4] (NO3)2 as the metal precursor at a pH = 9. The resulting catalysts were characterized using both CO and H2 chemisorption, transmission electron microscopy, and in-situ UV reflectance spectroscopy. Pretreatment in H2 resulted in poor Pd dispersions while pretreatment in He or Ar resulted in very high dispersions. Pretreatment in O2 resulted in moderate dispersions. The results are explained by considering the chemical structure of the adsorbed surface complex under different pretreatment conditions. The chemistry of the decomposition process is considered in detail.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Catalysis letters 54 (1998), S. 5-8 
    ISSN: 1572-879X
    Schlagwort(e): carbon measurements ; coke ; FTIR ; TGA ; sulfated zirconia ; isomerization ; n‐butane
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract A useful, high‐sensitivity method for quantifying small amounts of coke on a catalyst was developed. A TGA/FTIR technique was used. Gases evolved from the sample during the thermogravimetric analysis were transferred from the furnace by a purge gas to the flow cell of an FTIR. The intensity of the infrared spectra of evolved gases, such as CO2, was measured as a function of time and displayed as a chromatogram. Integration of the chromatograms was compared to that of a standard sample and gave the amount of coke deposited on the catalyst. The carbon deposition on sulfated sol–gel zirconia in the isomerization of n‐butane at 200°C was measured. The carbon content was 0.013 wt% following deactivation for 15 min and 0.06 wt% after 180 min.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...