GT-BTX™: Exceptional aromatics recovery

GT-BTX™ is Sulzer's proprietary aromatics recovery technology, engineered to extract benzene, toluene, and xylenes (BTX) from refinery and petrochemical streams through an advanced extractive distillation process and top-performance extraction solvent. Unlike conventional liquid-liquid extraction and extractive distillation systems that rely on sulfolane, N-formylmorpholine (NFM), N-methyl-2-pyrrolidone (NMP), or glycol solvents, GT-BTX™ highly integrated two-column design with the Techtiv™ solvent deliver exceptional separation performance at significantly lower capital and operating cost.

The process accepts a broad range of BTX-rich feedstocks — including reformate, pyrolysis gasoline (pygas), and coke oven light oil (COLO) without special feed preparation. Whether you are designing a grassroots aromatics recovery unit, or revamping an existing extraction system for better performance or higher throughput, GT-BTX™ provides the engineering flexibility and proven performance to meet your project requirements.

The Techtiv™ advantage

Sulzer's proprietary Techtiv™ extractive distillation solvent delivers superior selectivity and solvency compared to all conventional solvents commercially available for aromatics extraction — enabling higher recovery rates, lower energy consumption, and nitrogen-free benzene product in a single integrated process.

01 Capacity uplift
Up to 100% throughput gain within the existing footprint, no new columns in most cases.

02 Energy savings
20–30% lower steam demand and utility OPEX from day one of operation.

03 Higher purity
≥99.99 wt% chemical-grade BTX with nitrogen-free benzene product.

04 High recovery
≥99.9% aromatics recovery to capture entire petrochemical value.

05 Less corrosion
Carbon steel construction and smaller solvent inventory, lower total cost of ownership over the unit's life.

06 Fast payback
Payback typically <2 years.

1

Extractive distillation column (EDC)

BTX-rich feed is preheated with hot circulating solvent and introduced at the mid-point of the Extractive Distillation Column (EDC). Lean Techtiv™ solvent is fed from an upper inlet, selectively extracting aromatic components into the column bottoms through a vapor/liquid distillation mechanism. Non-aromatic hydrocarbons — paraffins and naphthenes, even olefins if there is any — exit overhead as raffinate, with a portion returned as reflux to wash back any entrained solvent. The result is a clean separation of BTX-rich solvent from the non-aromatic stream in a single column pass.

3

Aromatics fractionation

The mixed BTX overhead stream from the SRC is directed to a downstream fractionation section, where individual aromatic products — benzene, toluene, and xylenes — are separated to chemical-grade specifications. GT-BTX™ consistently produces benzene at ≥99.99 wt% purity and ≥99.9% recovery, meeting the most stringent international petrochemical and refining industry standards. Benzene produced via GT-BTX™ is nitrogen-free, a direct result of Techtiv™ solvent's highest selectivity.

2

Solvent recovery column (SRC)

Rich solvent from the base of the EDC is routed to the Solvent Recovery Column (SRC), operated under vacuum to minimize thermal stress on the solvent and reduce energy demand. Aromatics are stripped overhead and recovered as a mixed BTX product stream, while lean Techtiv™ solvent is continuously recovered from the column base and recirculated back to the EDC.