MTBE Unit - 18,000 BPD. The Methyl Tertiary Butyl Ether (MTBE) unit is designed to process a mixed butanes - butenes feed producing MTBE product by a selective reaction of isobutene and methanol. The unit can be divided into five sections a) Feed Section, b) MTBE Reactor Section, c) MTBE Recovery Section, d) Methanol Extraction Section, and e) Methanol Recovery Section