S-OIL Aromatics Complex No. 1 Liquid-Phase Xylene Isomerization Project Passes FID

en.Wedoany.com Reported - On September 10, the liquid-phase xylene isomerization (LPI) project at S-OIL Aromatics Complex No. 1 passed its final investment decision (FID). The project will adopt the liquid-phase xylene isomerization technology provided by Axens, and the unit is planned to be installed at S-OIL Aromatics Complex #1, with operation expected to commence in the second quarter of 2027. The two parties previously signed a technology licensing agreement at the end of 2024, and this FID moves the project from the technology licensing stage into the engineering implementation stage.

Axens' scope of work this time includes LPI technology licensing, the process design package, and technical services during project implementation and start-up. The technology will be used in the xylene loop system of S-OIL Aromatics Complex No. 1 to re-adjust the xylene isomer composition in the C8 aromatics stream remaining after paraxylene separation, and to operate in coordination with the existing gas-phase isomerization unit. The project has now clearly defined the technology supplier, process route, and planned start-up time.

The liquid-phase xylene isomerization unit is part of the xylene loop section of an aromatics complex. Technical information published by Axens shows that this route is used to process the paraxylene-lean C8 aromatics stream produced by the paraxylene separation unit, reforming a mixed xylene close to equilibrium composition through isomerization, which is then returned to the downstream separation system. The LPI technology adopted by the project is owned by ExxonMobil, with Axens responsible for licensing and engineering application, and it has already been industrially applied in multiple aromatics complexes.

S-OIL's existing aromatics production system includes two aromatics complexes. Company public information shows that its total paraxylene annual capacity is approximately 1.85 million tons and its benzene annual capacity is approximately 600,000 tons. Among them, Aromatics Complex No. 2 was commissioned in 2011, including the No. 2 xylene center with an annual capacity of 1.05 million tons of paraxylene, as well as aromatization-related facilities with an annual capacity of 300,000 tons of benzene. This LPI project is explicitly installed at Aromatics Complex No. 1 and is not part of the expansion of Aromatics Complex No. 2.

S-OIL previously also implemented the SUPER project to upgrade existing refining and petrochemical facilities, including the revamp of aromatics complexes. Parameters of the SUPER project disclosed by the company show that after the relevant revamp was completed, paraxylene output increased by approximately 5%, and benzene output increased by more than 8%. This newly built LPI unit is a new process optimization project at Aromatics Complex No. 1, focusing on adjusting the isomerization configuration in the xylene loop.

Axens' LPI technology can be used in combination with a gas-phase ethylbenzene conversion-type xylene isomerization unit. Its published technical information shows that the liquid-phase isomerization route does not require the high-temperature reaction conditions needed by the gas-phase system, and by adjusting the liquid-phase and gas-phase isomerization loads, the energy consumption of the xylene loop system can be reduced. This S-OIL project will adopt this combined approach to optimize the operation of the existing aromatics unit.

According to the current project timeline, S-OIL and Axens completed the signing of the LPI technology licensing agreement at the end of 2024, the project passed FID in September 2026, and Axens will subsequently continue to provide the process design package and technical support for project implementation, with the unit planned to start up in the second quarter of 2027.