On July 1, 1998 Sunoco purchased AlliedSignal's phenol plant, located in the Frankford area of Philadelphia, and the plant's merchant customer base. The acquisition places Sunoco chemicals in a strong integrated position from refinery feedstocks through to chemical intermediates phenol and acetone.

The Frankford plant currently manufactures more than 1 billion pounds of phenol, 620 million pounds of acetone and 70 million pounds of alpha-methylstyrene, making it the largest producer of the basic chemicals in North America and one of the two largest in the world. Phenol is the main building block chemical in the production of nylon and is also used to make pharmaceuticals, resins and polycarbonates. Acetone is used to make acrylic sheet, printing inks, paints and varnishes.