David Lynch - NASA

Oxygen Production & Lunar Regolith Simulant:Pyrometallurgical ProcessingReaction SchemesHydrogen ReductionFeTiO 3 + H 2 (g) → TiO 2 + Fe + H 2 O(g)Carbothermic ReductionFeTiO 3 + CO(g) → TiO 2 + Fe + CO 2 (g)CO 2 (g) + C = 2CO(g)with production of O 2 through electrolysis of H 2 O(l)or CO 2 (g). Thus Mare soils with a high ilmenitecontent are prime candidates for simulation.NASA Lunar Regolith Simulant Materials Workshop Jan. 2005

Reduction of TiO 2Investigation T (K) P Total % H 2 O/Ti molar ratio in productZhao & Shadmann 11001160122312900.93 atm 3.421.981.961.94Zhao & Shadmann 1223 0.93 atm 6.4 1.94Zhao & Shadmann 1023122312900.93 atm 14.71.901.831.83Allen et al. 132313731 atm 100 1.831.75Bullard & Lynch 1020 –12056 – 18 Torr1001.501255126026 Torr1001.0 ???NASA Lunar Regolith Simulant Materials Workshop Jan. 2005

glass2H(g) = H 2(g)ilmenite oriron silicateImpact ofhydrogen &defects onreaction ratesgas orplasmadefectsFeH 2(g) + S = H 2S(g)25 μmX = (D . t) 1/2diffusionT = 800 o CH 0.01 secH 21.0 secH 2O 8.7 hrNASA Lunar Regolith Simulant Materials Workshop Jan. 2005

Oxygen Production & Lunar Regolith Simulant:Processing (Reduction)Ore Properties• feed composition• particle size & size of ilmenitegrains in particles• availability of ilmenite forreaction• specific heat of feed• surface area• porosity• particle strength - before andafter processingDesired Attributes forProcessing• high reactivity fordesired products• minimize volatile traceelements (S ??)• maximize production pervolume of oreprocessed• controlled particle size(fluidization & timeof reaction)• bed stabilityNASA Lunar Regolith Simulant Materials Workshop Jan. 2005