Kinetics and mechanism of isobutene formation from t-butanol in hot liquid water
- Hawaii Natural Energy Inst., Honolulu, HI (United States). Dept. of Mechanical Engineering Univ. of Hawaii, Honolulu, HI (United States)
Isobutene is the only product of the uncatalyzed and acid-catalyzed dehydration of tert-butanol in compressed liquid water at 250 C. The uncatalyzed dehydration reaction is fast: equilibrium is established after about 30 s. Only one of many chemically-motivated kinetic models is able to fit all the experimental data. This model presumes a heterolytic dehydration mechanism that involves protonated alcohol, carbocation, di-tert-butyl ether, and protonated ether as intermediates. The model permits tert-butanol to dissociated as both an Arrhenius acid and a Bronsted acid while catalyzing its dehydration to isobutene. The pK[sub a] of tert-butanol at 250 C is predicted to be about 9, whereas its value at normal temperature and pressure is 18. This 10[sup 9] increase in the K[sub a] value of tert-butanol hints of the promising new world of reaction chemistry in near- and supercritical water.
- OSTI ID:
- 6845750
- Journal Information:
- AIChE Journal (American Institute of Chemical Engineers); (United States), Journal Name: AIChE Journal (American Institute of Chemical Engineers); (United States) Vol. 40:9; ISSN 0001-1541; ISSN AICEAC
- Country of Publication:
- United States
- Language:
- English
Similar Records
Homogeneous catalysis of ethyl tert-butyl ether formation from tert-butyl alcohol in hot, compressed liquid ethanol
Bronsted Acid Catalyzed Dehydration of Neat Supercritical tert-Butanol in a Capillary Micro-Reactor
Related Subjects
100200* -- Synthetic Fuels-- Production-- (1990-)
2-METHYLPROPENE
ALCOHOLS
ALKENES
AQUEOUS SOLUTIONS
BUTANOLS
CHEMICAL REACTION KINETICS
DEHYDRATION
DISPERSIONS
HYDROCARBONS
HYDROXY COMPOUNDS
KINETICS
MATHEMATICAL MODELS
MIXTURES
ORGANIC COMPOUNDS
REACTION INTERMEDIATES
REACTION KINETICS
SOLUTIONS
SYNTHESIS