Methyl Tert-Butyl Ether (MTBE) Synthesis with a Reactive Distillation Unit
This Demonstration simulates a reactive distillation column that produces methyl tert-butyl ether (MTBE).
The column is fed with a vapor mixture composed of 66.66% mole of -butane (an inert component) and 33.33% mole of iso-butene and a liquid composed of pure methanol. Both feeds are introduced at stage 9. The reactive stages range from 3 to 9. The column has 16 stages, a partial reboiler, and a total condenser. The reaction taking place is the following: iso-butene + methanol ⇌ MTBE.
For low Damköhler numbers (with molar hold-up equalling zero), no MTBE is formed and the only species present in the column are -butane, iso-butene, and methanol (see first snapshot).
At moderate Damköhler numbers, we get low conversions (see second snapshot).
Finally, at high Damköhler numbers, we get almost pure MTBE as a bottom and a mixture mainly composed of -butane (88 mole %); this composition is close to the binary nonreactive azeotrope between methanol and -butane (labelled Az in the ternary diagram).
F. Chen, R. S. Huss, M. F. Malone, and M. F. Doherty, "Simulation of Kinetic Effects in Reactive Distillation," Computers and Chemical Engineering, 24(11), 2000 pp. 2457–2472.