2. GT-BTX®
TechnologyLicensing
Engineered to Innovate
GT-BTX®: Aromatics Recovery
Using Extractive Distillation
GT-BTX® is an aromatics recovery technology that uses
extractive distillation to remove benzene, toluene and
xylene (BTX) from refinery, petrochemical or coke oven
aromatics streams such as catalytic reformate, pyrolysis
gasoline or coke oven light oil (COLO). With lower capital
and operating costs, simplicity of operation, a wider range
of feedstock and solvent performance, extractive distillation
is superior to conventional liquid-liquid extraction
processes. Flexibility of design allows use for grassroots
aromatics recovery units, debottlenecking, or expansion of
conventional extraction systems.
GTC’s GT-BTX process is a result of extensive testing of
extractive distillation solvents and blends. Our experience
indicates that certain combinations of solvent components
enhance extraction performance. Co-solvents also provide
an additional parameter for the optimization of unit
performance (e.g., stability, mass transfer efficiency).
The GT-BTX process utilizes the Techtiv-100 extractive
distillation solvent which provides optimum extractive
distillation performance.
GT-BTX process has no special feed preparation
requirements and is capable of handling a wide-range
(BTX) feedstock while producing very high aromatics
purities (99.99 wt.% plus) at high recoveries (99.9 % plus).
Process Overview
The flow scheme of the GT-BTX process consists of two
columns: an extractive distillation column (EDC) and a
solvent recovery column (SRC).
Since the basic separation in the GT-BTX process is
achieved by distillation, the operation of the unit is
very simple and intuitive. Control of the main process
parameters are achieved in a manner similar to that of a
regular distillation column.
Hydrocarbon feed is preheated with hot circulating solvent
and fed at a mid-point into the EDC. Lean solvent is fed
at an upper point and selectively extracts the aromatics into
the tower bottoms in a vapor/liquid distillation operation.
The non-aromatics hydrocarbons exit from the top of the
column. A portion of the overhead stream is returned to
the top of the column as reflux, which washes back any
entrained solvent.
Rich solvent from the bottom of the EDC is routed to the
SRC, where the aromatics are stripped overhead. The SRC
is operated under a vacuum to reduce the boiling point at
the bottom of the column.
Lean solvent from the bottom of the SRC is passed
through a heat exchanger before returning to the EDC. A
small portion of the lean circulating solvent is processed in
a solvent regeneration step to remove heavy decomposition
products.
The SRC overhead mixed aromatics product is routed to
the purification section, where it is fractionated to produce
chemical-grade benzene, toluene and xylenes.
Advantages
The benefits of extractive distillation, particularly those
highlighted by GT-BTX technology, may be summarized
as follows:
• Simple two-column ED system which requires 30-40
percent lower capital cost than conventional liquid-
liquid extraction systems
• Carbon steel construction throughout
• Smaller plot requirement than other systems
• Lower solvent inventory that further reduces investment
requirement
• Solvent blend exhibits highest selectivity among all
others in commercial use. Solvent properties allow wide
boiling range materials (C5- C9) to be fed into unit,
with varying aromatics content
• A short time is required to stabilize unit (few hours vs.
few days with liquid-liquid extraction systems)
• Lowest specific energy consumption (20-30 percent less
than others)
GTCTechnology 1001 S. Dairy Ashford, Suite 500 Houston,Texas 77077 USA Main +1-281-597-4800 Toll Free +1-877-693-4222
inquiry@gtctech.com | www.gtctech.com
3. GTCTechnology Engineered to Innovate
• Very low solvent consumption and circulation rates
• Higher product purity and aromatic recovery
• Insignificant fouling compared to liquid-liquid
contactors
• The benzene product from GT-BTX is nitrogen free.
Unlike some competing solvents, GTC’s solvent is
free of basic nitrogen containing components, which
permanently poison the catalyst in many benzene
consuming units
Economic Analysis
Engineered to Innovate
To learn more about GTC Technology’s leading-edge
technology solutions and the many ways we can help
improve your operations and profitability, call us today
at +1-281-597-4800, e-mail us at inquiry@gtctech.com
or visit our Web site at http://www.gtctech.com.
ExtractiveDistillationColumn
SolventRecoveryColumn
Raffinate Aromatics
Lean Solvent
Hydrocarbon
Feed
Aromatics-rich
Solvent
GT-BTX®
An aromatic-rich stream is fed to the Extractive Distillation Column (EDC) in the GT-BTX unit. Non-aromatics are separated and leave the top of
the EDC as raffinate. Aromatics are extracted in rich solvent and sent to the Solvent Recovery Column (SRC). Lean solvent from the SRC bottom
is recirculated back to the EDC. Extract from the SRC overhead is sent to the fractionation section to produce high-purity benzene, toluene and
xylenes.
Basis 12,000 BPSD reformate or pygas
Erected Cost $15MM (ISBL, 2009 U.S. Gulf Coast Basis)
GTCTechnology 1001 S. Dairy Ashford, Suite 500 Houston,Texas 77077 USA Main +1-281-597-4800 Toll Free +1-877-693-4222
inquiry@gtctech.com | www.gtctech.com
