Boston University College of Engineering
Department of Manufacturing Engineering
Rachel DeLucas, M.S. Candidate
M.S. Thesis Presentation
Friday, April 18, 2008
15 Saint Mary’s Street, Room 116
Professor Uday Pal, Advisor
Professor Soumendra N. Basu
Professor Adam C. Powell
Title: Scale-Up And Mathematical Modeling Of The Solid Oxide Membrane Process For The Direct Reduction Of Magnesium From Magnesium Oxide
Abstract: The Solid Oxide Membrane (SOM) process is an energy efficient process for the production of metals directly from their oxides. The Mg-SOM process employs an yttria-stablized zirconia membrane filled with liquid tin as an anode to deoxidize a molten ionic flux containing dissolved magnesium oxide. The deoxidation is achieved by the membrane’s excellent ionic conductivity at high temperatures (1150°C in this case). Dissociated oxygen ions are transported across the SOM to be oxidized at the tin anode. Magnesium vapor evolves at the stainless steel cathode and is carried by inert gas (argon) to a cooler chamber where it condenses into a high purity solid metal.
This study extends the previous proof of concept study of the Mg-SOM process (Krishnan, 2006) by testing the viability of a larger-scale reactor. Two dimensional and three dimensional mathematical modeling was used to further understand the Mg-SOM system. The viability of using the Mg-SOM process on a large scale was shown by fabricating and testing a reactor featuring three zirconia tubes. In addition, an exploration of the magnesiothermic reduction of titanium dioxide was made. Magnesium vapor generated using the Mg-SOM process was directed at titanium dioxide powder seated in a crucible. Titanium dioxide was successfully reduced to a titanium compound containing significantly less oxygen.