Laboratory experiments were conducted to investigate the vaporization behavior of nine trace elements including beryllium, vanadium, chromium, manganese, cobalt, nickel, zinc, arsenic, and lead during coal combustion and pyrolysis below 1150 degreesC. Zinc, lead, and arsenic exhibited greater volatility than the rest of the trace elements, and their vaporization behavior depended on the atmosphere and heating rate. Zinc and lead highly volatilized during pyrolysis and rapid-heating combustion, while they only slightly volatilized in slow-heating combustion. Arsenic volatilized during the rapid-heating combustion but almost entirely remained in the char or ash in the case of pyrolysis and slow-heating combustion. Thermodynamic analysis suggests that carbothermic reactions of zinc- and lead-bearing compounds promote the formation of metallic zinc and lead vapors. Interactions of arsenic with the mineral components in coal contribute to little vaporization loss of arsenic in the pyrolysis and slow-heating combustion probably because of the formation of thermally stable species such as ferric arsenide (FeAs) and calcium arsenate (Ca-3(AsO4)(2)).