High-temperature rate constant determination for the reaction of OH with iso-butanol.

Abstract

This work presents the first direct experimental study of the rate constant for the reaction of OH with iso-butanol (2-methyl-1-propanol) at temperatures from 907 to 1147 K at near-atmospheric pressures. OH time-histories were measured behind reflected shock waves using a narrow-linewidth laser absorption method during reactions of dilute mixtures of tert-butylhydroperoxide (as a fast source of OH) with iso-butanol in excess. The title reaction's overall rate constant (OH + iso-butanol →(k(overall)) all products) minus the rate constant for the β-radical-producing channel (OH + iso-butanol →(k(β)) 1-hydroxy-2-methyl-prop-2-yl radical + H(2)O) was determined from the pseudo-first-order rate of OH decay. A two-parameter Arrhenius fit of the experimentally determined rate constant in the current temperature range yields the expression (k(overall) - k(β)) = 1.84 × 10(-10) exp(-2350/T[K]) cm(3) molecule(-1) s(-1). A recommendation for the overall rate constant, including k(β), is made, and comparisons of the results to rate constant recommendations from the literature are discussed.

• Authors: Genny A Pang, Ronald K Hanson, David M Golden, Craig T Bowman
• Journal: The journal of physical chemistry. A (J Phys Chem A) Vol. 116 Issue 19 Pg. 4720-5 (May 17 2012) ISSN: 1520-5215 [Electronic] United States
• PMID: 22515280 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Butanols
• Water
• Hydroxyl Radical
• isobutyl alcohol
• tert-Butylhydroperoxide

Topics

• Butanols (chemistry)
• Hydroxyl Radical (chemistry)
• Kinetics
• Temperature
• Water (chemistry)
• tert-Butylhydroperoxide (chemistry)