Advanced

Hydrogen adsorption on two catalysts for the ortho- to parahydrogen conversion : Cr-doped silica and ferric oxide gel

Hartl, Monika LU ; Gillis, Robert Chad; Daemen, Luke; Olds, Daniel P; Page, Katherine; Carlson, Stefan LU ; Cheng, Yongqiang; Hügle, Thomas; Iverson, Erik B and Ramirez-Cuesta, A J, et al. (2016) In Physical Chemistry Chemical Physics 18(26). p.17281-17293
Abstract

Molecular hydrogen exists in two spin-rotation coupled states: parahydrogen and orthohydrogen. Due to the variation of energy with rotational level, the occupation of ortho- and parahydrogen states is temperature dependent, with parahydrogen being the dominant species at low temperatures. The equilibrium at 20 K (99.8% parahydrogen) can be reached by natural conversion only after a lengthy process. With the use of a suitable catalyst, this process can be shortened significantly. Two types of commercial catalysts currently being used for ortho- to parahydrogen conversion are: iron(iii) oxide (Fe2O3, IONEX®), and chromium(ii) oxide doped silica catalyst (CrO·SiO2, OXISORB®). We investigate the interaction of ortho- and parahydrogen with... (More)

Molecular hydrogen exists in two spin-rotation coupled states: parahydrogen and orthohydrogen. Due to the variation of energy with rotational level, the occupation of ortho- and parahydrogen states is temperature dependent, with parahydrogen being the dominant species at low temperatures. The equilibrium at 20 K (99.8% parahydrogen) can be reached by natural conversion only after a lengthy process. With the use of a suitable catalyst, this process can be shortened significantly. Two types of commercial catalysts currently being used for ortho- to parahydrogen conversion are: iron(iii) oxide (Fe2O3, IONEX®), and chromium(ii) oxide doped silica catalyst (CrO·SiO2, OXISORB®). We investigate the interaction of ortho- and parahydrogen with the surfaces of these ortho-para conversion catalysts using neutron vibrational spectroscopy. The catalytic surfaces have been characterized using X-ray absorption fine structure (XAFS) and X-ray/neutron pair distribution function measurements.

(Less)
Please use this url to cite or link to this publication:
author
, et al. (More)
(Less)
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Physical Chemistry Chemical Physics
volume
18
issue
26
pages
13 pages
publisher
The Royal Society of Chemistry
external identifiers
  • Scopus:84976877606
  • WOS:000379482100018
ISSN
1463-9084
DOI
10.1039/c6cp01154c
language
English
LU publication?
yes
id
d7842671-8cec-40e4-9573-bb6e9d8e9f0f
date added to LUP
2016-05-09 13:23:21
date last changed
2017-02-16 15:25:44
@article{d7842671-8cec-40e4-9573-bb6e9d8e9f0f,
  abstract     = {<p>Molecular hydrogen exists in two spin-rotation coupled states: parahydrogen and orthohydrogen. Due to the variation of energy with rotational level, the occupation of ortho- and parahydrogen states is temperature dependent, with parahydrogen being the dominant species at low temperatures. The equilibrium at 20 K (99.8% parahydrogen) can be reached by natural conversion only after a lengthy process. With the use of a suitable catalyst, this process can be shortened significantly. Two types of commercial catalysts currently being used for ortho- to parahydrogen conversion are: iron(iii) oxide (Fe2O3, IONEX®), and chromium(ii) oxide doped silica catalyst (CrO·SiO2, OXISORB®). We investigate the interaction of ortho- and parahydrogen with the surfaces of these ortho-para conversion catalysts using neutron vibrational spectroscopy. The catalytic surfaces have been characterized using X-ray absorption fine structure (XAFS) and X-ray/neutron pair distribution function measurements.</p>},
  author       = {Hartl, Monika and Gillis, Robert Chad and Daemen, Luke and Olds, Daniel P and Page, Katherine and Carlson, Stefan and Cheng, Yongqiang and Hügle, Thomas and Iverson, Erik B and Ramirez-Cuesta, A J and Lee, Yong Joong and Muhrer, Günter},
  issn         = {1463-9084},
  language     = {eng},
  month        = {05},
  number       = {26},
  pages        = {17281--17293},
  publisher    = {The Royal Society of Chemistry},
  series       = {Physical Chemistry Chemical Physics},
  title        = {Hydrogen adsorption on two catalysts for the ortho- to parahydrogen conversion : Cr-doped silica and ferric oxide gel},
  url          = {http://dx.doi.org/10.1039/c6cp01154c},
  volume       = {18},
  year         = {2016},
}