PEP Review 95-1-4R
Butanediol from n-Butane via Maleic Acid Hydrogenation
Published: February 1998
This review presents PEP's evaluation of two-step technology to produce butanediol (BDO) via oxidation of n-butane to maleic acid, followed by hydrogenation of maleic acid to BDO. The design is based on BP patents and is believed to be representative of the GEMINOX™ process, which is currently being offered for license by BP/Lurgi.
The distinguishing technical feature of the process is direct hydrogenation of maleic acid in the aqueous quench effluent from the oxidation reaction. Although not yet commercial, this design is expected to provide major equipment and utility cost savings compared with alternative maleic/BDO technology. The GEMINOX design also includes a fluidized bed reactor for oxidation of n-butane to maleic acid. Fluidized bed reactors are a relatively recent innovation for maleic acid production, offering capital and operating cost savings over the older fixed-bed design.
PEP's analysis indicates that capital for the GEMINOX-type design should be less than for all other routes for BDO production. Operating costs are low because of the inherently inexpensive n-butane raw material and steam credits from the oxidizer.