This paper describes the process of gallium removal from Ga2O3 -doped CeO2−x a surrogate for weapons-grade PuO2−x. Gallium is removed from the surrogate feedstock material using thermal techniques. An Ar-6% H, gas was used in order to reduce the oxide to gaseous Ga2O. Experimental results were shown in the temperature range of 600°C to 1200°C as a function of time and sample geometry. The results to date have shown that CeO2−x is a very good surrogate for PuO2−x.