Thermodynamic simulation of hydrogen reduction of NbCl₅ to produce Nb metal powder

A thermodynamic simulation program for Nb powder production process by hydrogen reduction of NbCl₅ in argon was developed by using SimuSage Software, which is a component library used in the developing of process simulation. The effects of the key parameters such as evaporation temperature, loading gas amount (Ar (g)), reduction temperature, H₂ (g) amount and collection temperature were studied by the simulation program. The results show that the evaporation rate of NbCl₅ (s) and the content of NbCl₅ (g) in gas are dependent upon the evaporation temperature and the amount of Ar (g) used. To get Nb (s) as the unique solid product, a minimum H₂ (g) amount of 20 mol per mol NbCl₅ is needed when the reduction temperature is 1000°C. High temperature of collection is helpful to the purity of the solid Nb powder product.