Abstract
To obtain the vapor pressure data of PbO in the PbO base slags with the high content of PbO, a transpiration method using a vertical volatilization chamber was developed and the vapor pressures were determined at 1, 423 and 1, 473 K for liquid PbO-FeO1.5-CaO-SiO2 and PbO-ZnO-FeO1.5-CaO-SiO2 slags nearly corresponding to those in the oxidation zone of the QSL lead smelting furnace. For any slag investigated, the activity of PbO was found to present a negative deviation from the Raoultian behavior and the activity coefficient of PbO showed a minimum value at the mole fraction of PbO in the slag with about 0.5. It was found that the acitivity coefficient of PbO increased with increasing Q of the slag, defined by Q = mass % CaO/(mass % SiO2 + mass % CaO). It was also clarified that the activity coefficient of PbO in the slag with ZnO was smaller than that in the slag without ZnO. The observed behaviors were explained qualitatively on the basis of the chemical affinity between PbO and other components in the slag. The partial pressures of various lead components in the gas phase were evaluated using the obtained thermodynamic data and it was suggested that the elemental lead species was predominant in the gas phase corresponding to the oxidation zone of the QSL furnace where the metallic lead phase coexists with the slag phase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
