NMR and Viscosity Investigation of Clathrate Hydrate Formation and Dissociation

Autor:	Waylon V. House, Walter G. Chapman,† and, Shuqiang Gao
Rok vydání:	2005
Předmět:	Chemistry General Chemical Engineering Clathrate hydrate Oxide General Chemistry Activation energy Industrial and Manufacturing Engineering Dissociation (chemistry) Subcooling chemistry.chemical_compound Nuclear magnetic resonance Deuterium Physical chemistry Hydrate Tetrahydrofuran
Zdroj:	Industrial & Engineering Chemistry Research. 44:7373-7379
ISSN:	1520-5045 0888-5885
Popis:	To better understand clathrate hydrate mechanisms, nuclear magnetic resonance (NMR) and viscosity measurements were employed to investigate tetrahydrofuran (THF) hydrate formation and dissociation processes. In NMR experiments, the proton spin lattice relaxation time (T1) of THF in deuterium oxide (D2O) was measured as the sample was cooled from room temperature down to the hydrate formation region. The D2O structural change around THF during this process was examined by monitoring the rotational activation energy of THF, which can be obtained from the slope of ln(1/T1) vs 1/T. No evidence of hydrate precursor formation in the hydrate region was found. T1 measurements of THF under constant subcooling temperature indicate that THF hydration shells do not undergo much structural rearrangement during induction. The T1 of THF was also measured as the sample was warmed back to room temperature after hydrate dissociation. T1 values of THF after hydrate dissociation were consistently smaller than those before hy...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::ea97a325561fca762089d3befd5dad8f https://doi.org/10.1021/ie050464b Zobrazit plný text záznamu