EXAFS and activity studies of the poisoning effect on Cl on Pt/Al{sub 2}O{sub 3} catalysts during oxidation reactions.

PDF Version Also Available for Download.

Description

The effect of Cl on the activity of Pt/Al{sub 2}O{sub 3} catalysts for methane oxidation has been studied by H{sub 2} and CO chemisorption, O{sub 2} isotopic exchange, kinetic studies and EXAFS spectroscopy. Catalysts containing 1.5% pt/Al{sub 2}O{sub 3} were prepared by incipient wetness from H{sub 2}PtCl{sub 6} and Pt(NH{sub 3}){sub 4}(NO{sub 3}){sub 2} precursors. Both reduced catalysts have similar dispersion (0.8) as determined by H{sub 2} chemisorption. At low methane concentration (0.3 vol.% CH{sub 4}, 16 vol.% O{sub 2}) the Cl-free catalyst was about 20 times more active during complete methane oxidation than the Cl-containing catalyst. Both CO chemisorption ... continued below

Physical Description

vp.

Creation Information

Gracia, F.; Wolf, E. E.; Miller, J. T. & Kropf, A. J. April 5, 2001.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. It has been viewed 13 times . More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Sponsor

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

The effect of Cl on the activity of Pt/Al{sub 2}O{sub 3} catalysts for methane oxidation has been studied by H{sub 2} and CO chemisorption, O{sub 2} isotopic exchange, kinetic studies and EXAFS spectroscopy. Catalysts containing 1.5% pt/Al{sub 2}O{sub 3} were prepared by incipient wetness from H{sub 2}PtCl{sub 6} and Pt(NH{sub 3}){sub 4}(NO{sub 3}){sub 2} precursors. Both reduced catalysts have similar dispersion (0.8) as determined by H{sub 2} chemisorption. At low methane concentration (0.3 vol.% CH{sub 4}, 16 vol.% O{sub 2}) the Cl-free catalyst was about 20 times more active during complete methane oxidation than the Cl-containing catalyst. Both CO chemisorption and oxygen exchange were observed on the Cl-free catalyst, whereas they were not detected on the Cl-containing catalyst. On the Cl-free catalyst, only Pt-Pt and Pt-O bonds were detected from the EXAFS results, while on the Cl-containing catalyst additional Pt-Cl bonds were present. The effect of chlorine on activity strongly depended on the reactant concentration. Exposure of the Cl-free catalyst to higher concentrations of methane (3 vol.% CH{sub 4}) reduced the activity to a level similar to that of the Cl-containing catalyst. Addition of HCl to the Cl-free catalyst rendered the activity identical to the catalyst prepared from Cl-containing precursors. A model is proposed to explain the mechanism of chloride poisoning, which appears to be site blocking.

Physical Description

vp.

Source

  • 9th International Symposium on Catalyst Deactivation (9th ISCD), Lexington, KY (US), 10/07/2001--10/10/2001

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Report No.: ANL/CMT/CP-104452
  • Grant Number: W-31-109-ENG-38
  • Office of Scientific & Technical Information Report Number: 799780
  • Archival Resource Key: ark:/67531/metadc742611

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • April 5, 2001

Added to The UNT Digital Library

  • Oct. 19, 2015, 7:39 p.m.

Description Last Updated

  • March 24, 2016, 9:17 p.m.

Usage Statistics

When was this article last used?

Yesterday: 0
Past 30 days: 2
Total Uses: 13

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Gracia, F.; Wolf, E. E.; Miller, J. T. & Kropf, A. J. EXAFS and activity studies of the poisoning effect on Cl on Pt/Al{sub 2}O{sub 3} catalysts during oxidation reactions., article, April 5, 2001; Illinois. (digital.library.unt.edu/ark:/67531/metadc742611/: accessed September 22, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.