In situ infrared study of catalytic decomposition of NO. Semiannually technical progress report, August 1, 1995--February 1, 1996

Technical Report · Mon Mar 04 04:00:00 EST 1996

DOI:https://doi.org/10.2172/225026· OSTI ID:225026

Chuang, S C; Tan, C D

During the first semi-annual period of the project, NO adsorption, CO adsorption, NO temperature-programmed desorption and decomposition (TPD), and temperature programmed reaction (TPR) of NO-CO have been studied over 0.5% wt% Rh/SiO{sub 2} catalysts by a combined infrared and mass spectrometric technique. Infrared study reveals that the high wavenumber Rh-NO{sup {delta}{minus}} at 1723-1740 cm{sup {minus}1} is the dominant adsorbate during TPD and TPR with NO:CO=1:1. During TPR, CO reduces part of Rh surface resulting in the formation of the low wavenumber Rh-NO{sup {delta}{minus}} at 1634-1680 cm{sup {minus}1}. Increasing CO partial pressure (i) promotes the formation of Rh to Rh{sup 0} sites, producing linear CO, (ii) increases the selectivity to N{sub 2}O below the light-off temperature, (iii) raises the light-off temperature, and (iv) promotes the formation of Si-NCO and Rh-NCO. Comparison of results of the present study with those of previous studies on 4 wt% Rh/SiO{sub 2} shows that different dispersion of Rh crystallites on SiO{sub 2} support results in significant variation in chemisorptive and reactive properties of Rh metal for NO-CO reaction.

• Research Organization: Akron Univ., OH (United States). Dept. of Chemical Engineering
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG22-95PC95224
• OSTI ID: 225026
• Report Number(s): DOE/PC/95224--T1; ON: DE96010219
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
40 CHEMISTRY
ADSORPTION
CARBON MONOXIDE
CATALYTIC EFFECTS
DECOMPOSITION
DESORPTION
EXPERIMENTAL DATA
INFRARED SPECTRA
MASS SPECTROSCOPY
NITRIC OXIDE
PROGRESS REPORT
REACTION INTERMEDIATES
RHODIUM
SILICA
SORPTIVE PROPERTIES