Anomalously large kinetic isotope effect

• Authors: David Krinkin
• Languages of publication: EN

Abstracts

EN

Activated diffusion of water between macromolecules in swollen cellulose is accompanied by anomalously high kinetic isotope effects of oxygen. The separation factor of heavy-oxygen water (H218O /H216O) is thousands of permilles instead of tens of permilles according to modern Absolute Rate Theory. This anomalous separation under usual conditions is disguised by the opposing process of very fast equalization to equilibrium through water-filled cellulose pores. This process is quicker by approximately 3 orders of magnitude than diffusion through the cellulose body. As a consequence, this opposition-directed equalization virtually eliminates the results of isotope separation. To reveal this anomaly it is necessary to suppress equalization, which was the primary problem for both discovery of this anomaly and its investigation. The method of investigating the anomalous separation in cellulose was developed with suppression of this negative influence. Discussion of the theoretical nature of the anomalous kinetic isotope effect is presented. This theoretical study would probably permit the discovery and use for isotope separation of the anomalously high isotope effect for other chemical elements, in particular, for those heavier than oxygen. [...]

Keywords

EN

isotopic water separation; membranes; oxygen; hydrogen

• Publisher: De Gruyter Open
• Journal: Open Chemistry
• Year: 2007
• Volume: 5
• Issue: 4
• Pages: 1019-1063

Dates

published

1 - 12 - 2007

online

12 - 9 - 2007

Contributors

author

David Krinkin

• Yozmot HaEmek Technological Incubator, P.O. Box 73, Migdal HaEmek, Israel, 23100

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Identifiers

DOI

10.2478/s11532-007-0048-2