ABSTRACT Proposal Number: 9414446 Principle Investigator: Nassaralla This is a study of the sources of hexavalent chromium in spent chrome- magnesite brick. The amount of chromium (VI) in new brick is correlated with the brick production process variables (firing temperature, bonding type, chemical composition). The effect of brick impurities on formation of hexavalent chromium is studied at various temperatures; an attempt is made to explain the relatively high levels of chromium (VI) in the cold face of the refractory relative to the hot face. Chrome-magnesite refractories are used extensively in the steel, copper, and glass industries. They are slowly consumed and must be replaced from time to time. Spent chrome-magnesite brick is classified as a hazardous waste because of its high levels of hexavalent chromium. Reduction or elimination of chromium (VI) formation would reduce disposal costs and environmental threat.
