The joint venture agreement was to have expired in 2020.
The SADAF complex, on 460 acres in Jubail, Saudi Arabia, comprises an ethylene plant, two styrene plants, a salt plant, an ethyl chloride-caustic plant, a methyl tertiary butyl ether plant, and a cogeneration plant.
It produces an average of more than 4 million tonnes/year of chemicals from ethane, benzene, methane, butane, and salt brine.
SABIC and Shell formed the venture in June 1980. Ethylene production began in October 1984.