PEP Review 91-2-4
Isobutene Production by Isomerization Of N-Butene
Published: February 1993
Since March 1992, Lyondell Petrochemical, Texas Olefins/Phillips, BP/Mobil, and IFP all have announced the development of one-step processes to isomerize n-butene to isobutene. Increasing demand for methyl tertiary-butyl ether (MTBE) worldwide, especially in the United States for cleaner burning gasoline, provides the primary incentive for isobutene production from n-butene. Traditionally, isobutene is available in the C4 streams from ethylene units and from refinery fluid catalytic cracking (FCC) units. These sources are inadequate to supply the increased demand for MTBE. As a result of isobutene shortages, the utilization rates for U.S. captive MTBE plants were below 65% between 1988 and 1990.
In this review, we evaluate the technical and economic aspects of MTBE production via integration of an n-butene isomerization unit into a petrochemical plant and into a refinery. The cost comparison shows that the desire to produce additional MTBE will be the main driving force for integrated n-butene isomerization units, since the most economical method of produc ing MTBE is from once-through isobutene only.