S-Oil Corp is preparing to take its No.1 residue fluid catalytic cracker (RFCC) unit in Onsan, South Korea, offline for a scheduled maintenance turnaround later this year, according to market sources.
A contact in South Korea said the refinery plans to begin the outage by mid-October 2025, with operations expected to remain suspended until the end of November. “The company is expected to start maintenance at the unit by mid-October 2025. The unit is slated to remain offline until end November 2025,” the source noted, adding that the exact start date may still be adjusted as preparations progress.
The Onsan RFCC unit processes around 73,000 barrels of crude per day and produces roughly 200,000 metric tons of propylene annually, making it a key contributor to both the refinery’s output and the region’s propylene supply. Market participants said they are closely watching for updates, as the shutdown could temporarily tighten propylene availability in Northeast Asia and influence spot pricing during the autumn trading period.
While feedstock inventories and alternative supply sources may cushion immediate effects, traders and downstream users in the olefins chain are preparing contingency plans in case of any extended downtime. Analysts also pointed out that the maintenance overlaps with other seasonal turnarounds in Asia, which could amplify regional market sensitivity to any delays.
