Simple relationships for estimating intraparticle transport effects for catalytically promoted endothermic reactions

PDF Version Also Available for Download.

Description

Relationships for estimating effectiveness factors for porous-solid-catalyzed fluid reactions can result from assuming approximations to temperature and concentration profiles. Approximations designed to simplify the outcome result in simple, explicit, analytic relationships for both isothermal and nonisothermal nth-order reaction systems. For isothermal systems, formulas developed predict effectiveness within 25% of the true isothermal effectiveness factors ({eta}`s) over the range 0.1 > {eta} > 0.99. For isothermal or endothermic reaction systems with {eta} > 0.65, errors are less than 10%. Even in the maximum-error region, estimates for endothermic systems are within a factor of two of those obtained by solution of the ... continued below

Physical Description

[50] p.

Creation Information

Brown, L. F. June 16, 1998.

Context

This report 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. More information about this report can be viewed below.

Who

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

Author

Sponsor

Publisher

  • Los Alamos National Laboratory
    Publisher Info: Los Alamos National Lab., Engineering Science and Applications Div., NM (United States)
    Place of Publication: New Mexico

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 report. Follow the links below to find similar items on the Digital Library.

Description

Relationships for estimating effectiveness factors for porous-solid-catalyzed fluid reactions can result from assuming approximations to temperature and concentration profiles. Approximations designed to simplify the outcome result in simple, explicit, analytic relationships for both isothermal and nonisothermal nth-order reaction systems. For isothermal systems, formulas developed predict effectiveness within 25% of the true isothermal effectiveness factors ({eta}`s) over the range 0.1 > {eta} > 0.99. For isothermal or endothermic reaction systems with {eta} > 0.65, errors are less than 10%. Even in the maximum-error region, estimates for endothermic systems are within a factor of two of those obtained by solution of the rigorous heat and mass transfer equations. For isothermal or endothermic systems with {eta} > 0.95, errors are less than 1%. Thus the formulas can also serve diagnostic uses that confirm presence or absence of significant internal heat or mass transport effects in porous reacting systems. Extension of the approach to non-nth-order reactions is possible; formulas are derived for simple isothermal and nonisothermal Langmuir-Hinshelwood reaction systems. Application of the work to exothermic reactions was not tested, but steeper gradients in such systems would tend to degrade accuracy of the relationships. The equations derived in this work are simpler and easier of application than any others proposed thus far.

Physical Description

[50] p.

Notes

OSTI as DE99001635

Source

  • Other Information: PBD: 16 Jun 1998

Language

Item Type

Identifier

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

  • Other: DE99001635
  • Report No.: LA-UR--98-2769
  • Grant Number: W-7405-ENG-36
  • DOI: 10.2172/307875 | External Link
  • Office of Scientific & Technical Information Report Number: 307875
  • Archival Resource Key: ark:/67531/metadc681477

Collections

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

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • June 16, 1998

Added to The UNT Digital Library

  • July 25, 2015, 2:20 a.m.

Description Last Updated

  • Nov. 3, 2016, 1:16 p.m.

Usage Statistics

When was this report last used?

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

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Brown, L. F. Simple relationships for estimating intraparticle transport effects for catalytically promoted endothermic reactions, report, June 16, 1998; New Mexico. (digital.library.unt.edu/ark:/67531/metadc681477/: accessed November 19, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.