Diffusion and Electrochemical Transport of Oxygen in Pbo–SiO₂Melts

Abstract

The diffusion of oxygen from the gas phase through PbO-Si0 2 melts to an underlying phase of liquid Pb is considerably enhanced when the metal phase is connected to the slag-gas interface by an electronic conductor. The connection may be made either internally, by a conductor which passes through the three phases, or by an external circuit. When the connection is made externally the increased transfer of oxygen is equivalent to the number of coulombs which pass. The increase in rate due to the electronic conductor is governed by the flow of current in the cell M, 02(g)/(PbOwhere M is the conductor and depends on the resistance in the circuit. The transport of oxygen may be enhanced, supp"essed or reversed by applying an appropriate EMF across the slag and metal phases. Resume-La diffusion d'oxygene a partir de l'etat-gaz, par la dissolution de PbO-Si02,jusqu'a un etat-liquide de base, est considerablement accrue quand l'etat-metal est relie a l'interface scorie-gaz par un conducteur electronique. La liaison peut etre realisee soit interieurement, par un conducteur passant par les trois etats, soit par un circuit exterieur. Quand cette liaison est realisee exterieurement, Ie transfer accru d'oxygene est equivalent au nombre d'ampere-secondes qui s'ecoule. L'augmentation en taux due au conducteur electronique est regie par Ie passage du courant dans la pile M, 02(g)/(PbO + Si02)(I)/Pb(I), M OU M est Ie conducteur et depend de la resistance dans Ie circuit. Le transport d'oxygene peut etre accru, supprime ou inverse en appliquant une FEM appropriee entre la scorie et les phases-metal.

Experimental evidence for electrochemical nature of the reaction between iron oxide in calcia-silica-alumina slag and carbon in liquid iron

“…External the reaction rate can be temporarily increased by "internally circuits have been established in other studies to observe a short circuiting" the slag layer. The positive effect on the short-circuit current [4][5][6]8,18] and open-circuit voltage between reaction rate of internally short circuiting the slag layer has slag and metal layers. [8,11,18] also been observed for oxygen transfer through PbO-SiO 2 The results obtained in experiment 6 ( Figures 13 and 14) can slags to liquid lead [8,9] and for the reaction between CO 2 gas now be explained.…”

“…The positive effect on the short-circuit current [4][5][6]8,18] and open-circuit voltage between reaction rate of internally short circuiting the slag layer has slag and metal layers. [8,11,18] also been observed for oxygen transfer through PbO-SiO 2 The results obtained in experiment 6 ( Figures 13 and 14) can slags to liquid lead [8,9] and for the reaction between CO 2 gas now be explained. When the FeO pellets fell on the surface of and Ag-S alloys separated by CaO-Al 2 O 3 -SiO 2 slags.…”

“…[3] carbon and by carbon dissolved in liquid iron, [6,7] on the is coupled with anodic partial reactions, such as the oxidation transfer of oxygen through PbO-SiO 2 slag to liquid lead, [8,9] of liquid iron, on the reaction between CO 2 gas and Ag-S alloys through CaO-Al 2 O 3 -SiO 2 slag, [10,11] on the desulfurization of liquid Fe (1 Fe sln) → Fe 2ϩ (1 slag sln) ϩ 2e Ϫ [4] Fe-Cr-S alloy using CaO-Al 2 O 3 and CaO-Al 2 O 3 -CaF 2 and of silicon, aluminum, manganese, or other elements in slags, [12][13][14][15] on the reduction of solid NiO, MnO 2 , and Cr 2 O 3 solution in liquid iron. They suggested that carbon particiby solid carbon, [16] and on the reduction of MnO from SiO 2 -pated in the reaction MnO-CaO-Al 2 O 3 slag by solid carbon.…”