The coal fly ash from a Chinese thermal power plant was vitrified after the addition of -10 wt% Na2O. The glass products have suitable viscosity at 1200 degreesC and displayed a good chemical durability. The heavy metals of Pb, Zn, Cr and Mn were successfully immobilized into the glass as determined by the toxicity characteristic leaching procedure method. Results indicate an interesting potential for the coal fly ash recycling to produce useful materials. (C) 2002 Elsevier Science Ltd. All rights reserved.