Application: The widely used UOP Butamer process is a high-efficiency, cost effective means of meeting the demands for the production of isobutane by isomerizing normal butane (nC4) to isobutane (i C4).
Motor-fuel alkylate is one blending component that has seen a substantial increase in demand because of its paraffinic, high-octane, lowvapor pressure blending properties. Isobutane is a primary feedstock for producing motor-fuel alkylate.
Description: UOP’s innovative hydrogen-once-through (HOT) Butamer process results in substantial savings in capital equipment and utility costs by eliminating the need for a product separator or recycle-gas compressor.
Typically, two reactors, in series flow, are used to achieve high onstream efficiency. The catalyst can be replaced in one reactor while operation continues in the other. The stabilizer separates the light gas from the reactor effluent.
A Butamer unit can be integrated with an alkylation unit. In this application, the Butamer unit feed is a side-cut from an isostripper column, and the stabilized isomerate is returned to the isostripper column. Unconverted n-butane is recycled to the Butamer unit, along with n-butane from the fresh feed. Virtually complete conversion of n-butane to isobutane can be achieved.
Feed: The best feeds for a Butamer unit contain the highest practical n-butane content, and only small amounts of isobutane, pentanes and heavier material. Natural gas liquids (NGL) from a UOP NGL recovery unit can be processed in a Butamer unit.
Yield: The stabilized isomerate is a near-equilibrium mixture of isobutane and n-butane with small amounts of heavier material. The light-ends yield from cracking is less than 1 wt% of the butane feed.