Technology

GT-BTX PluS^® is a variation of GT-BTX^® Extractive Distillation (ED) Technology that simultaneously removes Benzene, Toluene, Xylene and Thiophenic Sulfur Species from Refinery or Petrochemical Aromatic-containing Streams. The Technology helps produce low-Sulfur Gasoline that meets the 10 ppm limit of Sulfur without a change in Octane value. Another use of GT-BTX PluS^® is to generate Aromatics to produce Paraxylene without the requirement of a typical Naphtha Reformer Unit. The Aromatics recovery is especially attractive for use with Feedstocks produced from High-Severity Fluid Catalytic Cracking (FCC) operations.

The Process is optimally installed on the FCC Mid-Cut Naphtha Stream. GT-BTX PluS removes all Thiophenes and some of the Mercaptan Species from the FCC Gasoline Feed.  The Olefin-rich Raffinate can be sent directly to the Gasoline pool for Blending, or to a Caustic Treating Unit to remove the Mercaptan-type Sulfur Compounds before being sent to the Gasoline. The Desulfurized Aromatics Extract Stream can be directly fed into Petrochemical Production Units instead of Recycling to the Naphtha Reformer.

The optimum Feed is the Mid Fraction of FCC Gasoline from 70°C to 150°C.  This Material is fed to the GT-BTX PluS Unit, which extracts the Sulfur and Aromatics from the Hydrocarbon Stream.  The Sulfur-containing Aromatic Components are processed in a conventional Hydrotreater to convert the Sulfur into Hydrogen Sulfide (H₂S).  Because the portion of Gasoline being Hydrotreated is reduced in volume and free of Olefins, Hydrogen Consumption and operating costs are greatly reduced.  In contrast, conventional Desulfurization schemes must process the majority of the Gasoline through Hydrotreating Units to remove Sulfur, which inevitably results in Olefin Saturation, Octane downgrade and yield loss.