The companies said the plant, a 50-50 joint-venture project, is one of the largest of its kind in the world, and employs Lyondell's proprietary technology. The companies said the new plant has an annual capacity of 285,000 metric tons (625 million pounds) of propylene oxide and 635,000 mt (1.4 billion lbs.) of styrene.

Dan Smith, Lyondell president and CEO, said the plant and its "ideal location near the port of Rotterdam" provide a key production and distribution site for products marketed in Europe and exported overseas. He said the new plant accounts for roughly 5% of the world's propylene oxide capacity and makes Lyondell a significant styrene monomer producer in Europe. Lyondell said it is the world's largest producer of propylene oxide.

Propylene oxide is used to make polyurethane raw materials, and styrene monomer is used in coatings and plastics.

Tony Van Osselaer, a Bayer MaterialScience board member responsible for production and technology, said the new plant provides the company with long-term access to key raw materials for the polyurethane and plastics markets.

Lyondell said it estimates that worldwide demand for propylene oxide was approximately 5.1 million mt (11.2 billion lbs.) in 2003. Approximately 90% of that volume was used for the manufacture of polyols, propylene glycols and propylene glycol ethers. The remainder went into the manufacture of specialty products such as butanediol (BDO) and its derivatives.