A new high-temperature reactor that can draw power from conventional electricity as well as from a solar-thermal heating system could enable a cleaner, lower-energy route to lightweight magnesium alloys. The custom-made reactor was built by thermal processing equipment company Harper International (Buffalo, N.Y.; www.harperintl.com) in support of a research grant from the Dept. of Energy’s Advanced Research Projects Agency–Energy (ARPA-E; Washington, D.C.; arpa-e.energy.gov). The reactor will be used in the laboratory of Alan Weimer at the University of Colorado at Boulder (www.colorado.edu) for projects related to the high-temperature processing of magnesium oxide to obtain Mg metal.
Current methods to produce magnesium metal from MgO are batch processes that are not energy efficient, explains Harper sales engineer Brian Fuller. The hope is that the hybrid reactor can enable a continuous process that requires less energy and labor in the production of magnesium metal.
Harper’s system will be employed in the reaction of MgO with carbon at high temperatures to generate Mg vapor and carbon monoxide. “The reaction is known to be possible, but it’s very hard to carry out reliably and effectively,” Fuller says. The Mg vapor is converted to solid metal, while the CO is processed in downstream systems.
The research-scale reactor utilizes unique materials of construction and is designed to allow for tight control over pressure and temperature, Fuller points out. Harper engineers equipped the reactor with a mechanism to switch back and forth between electrical heating and concentrated solar-energy power, to mimic day-and-night cycles.