Intermediate chemicals produced by Flint Hills Resources include purified isophthalic acid, maleic anhydride and trimellitic anhydride and expandable polystyrene. The company uses some of the commodity chemicals produced in Corpus Christi, Texas, to manufacture the intermediates products made in the Joliet, Ill., facility. Flint Hills Resources also has a long-term agreement to receive PIA produced at a plant located in Geel, Belgium.

These intermediate chemicals, in addition to ethylene oxide, ethylene glycol, and styrene monomer, are used in the production of such diverse products as paints, wrinkle-resistant clothing, audio and videotapes, gasoline additives, and furniture seat cushions.