Hydrothermal reactions of methylamine

Kenneth M. Benjamin, Phillip E. Savage

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

We have examined the reactivity of methylamine in supercritical water (SCW) at temperatures between 386 and 500°C. The major products measured are ammonia and methanol. Batch reactor studies revealed a global reaction order of 0.66±0.11 for methylamine disappearance. For water densities less than 0.28 g/cm3 and pressures less than or equal to 250 atm, the effect of water on the reaction rate appears to be negligible, and there is little evidence of hydrolysis (very little methanol formed). Under these conditions, most typical of supercritical water oxidation (SCWO) reactors, the reaction seems to be governed by pyrolysis. The rate constant for methylamine disappearance in this region is described by an activation energy of 38±7 kcal/mol and a pre-exponential factor of 106.1±2.0 (mol/cm3)0.34 s-1. At higher water densities, hydrolysis becomes more important and the methanol yield increases with water density. Potential mechanisms for methylamine hydrolysis include SN2 and molecular mechanisms.

Original languageEnglish (US)
Pages (from-to)301-311
Number of pages11
JournalJournal of Supercritical Fluids
Volume31
Issue number3
DOIs
StatePublished - Nov 1 2004

Fingerprint

Water
water
Methanol
hydrolysis
Hydrolysis
methyl alcohol
reactors
Batch reactors
Ammonia
Reaction rates
pyrolysis
methylamine
ammonia
Rate constants
reaction kinetics
Pyrolysis
reactivity
Activation energy
activation energy
Oxidation

All Science Journal Classification (ASJC) codes

  • Chemical Engineering(all)
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry

Cite this

Benjamin, Kenneth M. ; Savage, Phillip E. / Hydrothermal reactions of methylamine. In: Journal of Supercritical Fluids. 2004 ; Vol. 31, No. 3. pp. 301-311.
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Hydrothermal reactions of methylamine. / Benjamin, Kenneth M.; Savage, Phillip E.

In: Journal of Supercritical Fluids, Vol. 31, No. 3, 01.11.2004, p. 301-311.

Research output: Contribution to journalArticle

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