2,2,3-Trimethylbutane (i.e., triptane) is a potential gasoline octane booster with a research octane number (RON) of 112. it is also used as a fuel additive and in comparative rate of thermal decomposition (CRTD) single-pulse surge tube studies[1-2].
2,2,3-Trimethylbutane (triptane) selectively forms from dimethyl ether at low temperatures on acid zeolites
[3].
We report herein the first selective catalytic conversion of DME to
triptane on halide-free catalysts,
specifically on crystalline solid
acids, at much lower reaction temperatures (453–493 K) and higher
DME pressures (60–250 kPa) than
in established methanol/DME to
hydrocarbon processes. Low temperatures avoid intervening skeletal
isomerization and b-scission of triptyl chains or their precursors. These
processes would otherwise occur
before the methylation events that
form the C7 chains containing the
triptane backbone, which desorb irreversibly as triptane.
[1] NOUR ATEF. Chemical kinetic study of triptane (2,2,3-trimethylbutane) as an anti-knock additive[J]. Combustion and Flame, 2019. DOI:10.1016/j.combustflame.2019.09.006.
[2] TSANG W. Comparative rate single-pulse shock tube studies on the thermal decomposition of cyclohexene, 2,2,3-trimethylbutane, isopropyl bromide, and ethylcyclobutane[J]. International Journal of Chemical Kinetics, 1970. DOI:10.1002/kin.550020406.
[3] JOHN?H. AHN; Enrique I Prof; Burcin Temel Dr. Selective Homologation Routes to 2,2,3-Trimethylbutane on Solid Acids?[J]. Angewandte Chemie International Edition, 2009. DOI:10.1002/anie.200900541.
