Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Noble metal catalysts for the hydrocracking of FT waxes
KTH, School of Chemical Science and Engineering (CHE).
2012 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Bifunctional catalysts consisting of palladium or platinum and supported on amorphous silica-alumina were prepared and tested in the hydrocracking of n-hexadecane, which is considered to be representative of n-paraffins in hydrocracker feeds. In addition to the evaluation of the  physicochemical properties, a comprehensive study on catalyst activity and selectivity has been conducted, in the full range of conversions.

A theoretical model was proposed to fit the experimental conversion-selectivity data. The n-hexadecane reactivity pattern was expressed in terms of a reaction network involving lumps consisting of monobranched and multibranched n-hexadecane isomers, and cracking products. Pseudo first order kinetics and irreversible reaction steps were assumed in order to obtain the kinetic constants of each step.

For the same metallic molar loading, a platinum-based catalyst proved more active than a palladium one. The reaction network model showed that cracking products were produced by means of a bifunctional mechanism on palladium catalysts, with n-hexadecane isomers as intermediates. However, on platinum catalysts, an additional monofunctional mechanism was observed. The noble metal catalyzes the hydrogenolysis of n-hexadecane without requiring any acid function. An increase in the platinum loading leads to an increase in the importance of this direct cracking route.

The deactivation in the platinum-based catalysts is only due to coke formation, which deactivates the metal sites. The regeneration by means of a Temperature-Programmed Oxidation does not lead to a complete recovery of the metal function, according to the volumetric chemisorption measurements and the experimental selectivity  data. Further work is required to determine the real causes.

Place, publisher, year, edition, pages
2012. , 98 p.
Keyword [en]
Hydrocracking, Fischer-Tropsch, Hexadecane, Platinum, Palladium
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:kth:diva-158477OAI: oai:DiVA.org:kth-158477DiVA: diva2:777025
Available from: 2015-01-08 Created: 2015-01-08 Last updated: 2015-01-08Bibliographically approved

Open Access in DiVA

fulltext(4359 kB)311 downloads
File information
File name FULLTEXT01.pdfFile size 4359 kBChecksum SHA-512
0718b819ea2ecc5bc967df9a3e4fcb2bc09fb88bfb2bd2593dd638dfee39f62987a774ef30ff0fe72623c540e9d27cee729b9bf9bc8032070a8c7862bf8ad4cf
Type fulltextMimetype application/pdf

By organisation
School of Chemical Science and Engineering (CHE)
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 311 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 158 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf