Disclosed herein is a rotary tube furnace configured to facilitate a chemical reaction between a solid mass and a gas in the furnace. The rotary tube furnace may comprise a reaction chamber extending through the furnace, the reaction chamber configured to control ingress and egress of each of the solid mass and the gas in the reaction chamber; a passage way configured to supply the solid mass to the reaction chamber; a passage way configured to supply the gas to the reaction chamber and circulate the gas through the reaction chamber; a heater providing heat to the reaction chamber and configured to control a reaction temperature in the reaction chamber; a magnetic field source in proximity to the reaction chamber for generating a magnetic field to one or more reaction zones of the reaction chamber; wherein the reaction chamber provides for mixing the solid mass and the gas.