Application: For more refiners, the issue of benzene in the gasoline pool is one of managing benzene production from the catalytic reformer. The two primary strategies to accomplish this goal include the minimization of benzene and benzene precursors in the catalytic reformer feed, or elimination of the benzene from the reformate after it is formed. The UOP BenSat process can be applied in either of these strategies. The process can operate in stand-along mode or in conjunction with C5 – C6 isomerization such as the UOP Penex-Plus process configuration.
Description: The UOP BenSat process was developed as a low-cost stand-alone option to treat C5 – C6 feedstocks that are high in benzene. Benzene is saturated to C6 naphthenes. The catalyst used in this process is highly selective for benzene saturation to C6 naphthenes.
Makeup hydrogen is provided in an amount slightly above the stoichiometric level required for benzene saturation. The heat of reaction associated with benzene saturation is carefully managed to control temperature rise across the reactor. Use of a relatively high space velocity in the reactor contributes to the unit’s cost-effectiveness.
Feed: Typical feeds include hydrotreated light straight-run (LSR) naphtha or light reformate streams. The Ben Sat process is designed to handle 30 vol% or more benzene in the feed. Sulfur suppresses activity, as expected for any noble-metal-based catalyst. However, the suppression effect is fully reversible by subsequent processing with clean feedstocks.
Yields: For feeds with 5–10 vol% benzene, the C5+ volumetric product yields are 101–106% of the feed. Because of high catalyst selectivity, hydrogen consumption is minimized and is near the stoichiometric level of three moles of hydrogen per mole of benzene saturated. The BenSat process saturates benzene without an increase in Rvp.