May 08, 2008. /Lesprom.com/. Koppers Holdings Inc. announced the retirement of Robert Cizik, who has been Chairman of the Board of Koppers Holdings Inc. since its formation in 2004, and of Koppers Inc. since 1999. Mr. Cizik will be replaced as Chairman by David M. Hillenbrand, who has been a Board member of Koppers Holdings Inc. since 2004 and of Koppers Inc. since 1999. Dr. Hillenbrand is currently the CEO of Carnegie Museums of Pittsburgh after retiring from Bayer AG as executive vice president of Bayer Polymers in 2003. Koppers is a global integrated producer of carbon compounds and treated wood products. Including its joint ventures, Koppers operates facilities in the United States, United Kingdom, Denmark, Australia, and China.