Extensive investigation in the two-stage hydrogen reduction process for fine molybdenum powder synthesis has been con-ducted. Reaction thermodynamic, kinetics, grain morphology transformation mechanism, grain morphology and grain size control have been studied in detail. Pilot scale development work has been performed. Stage one reduction is highly exo-thermic and it proceeds as MoO3 ??Mo4O11 ??MoO2. Mo4O11 exists as an intermediate product which is a stable phase and has needle shaped grain morphology. Desirable MoO2 morphology can be obtained if exothermic reaction is properly controlled in stage one reduction. The second stage reduction, MoO2 +H2 ??Mo + 2H2O is an endothermic reaction. The final product Mo inherits MoO2’s morphology. Mo product grain size and size distribution is determined by stage two reduc-tion. In both stages, grain morphology transformation mechanism follows nucleation of product phase and product phase crystal growth via chemical vapor transport. Volatile molybdenum oxide monohydrate, MoO2(OH)2, is the gas phase re-sponsible for the chemical vapor transport of Mo. Complete reduction system was designed and engineered based on this pilot development work. Optimized process parameters developed in pilot scale have been successfully scaled up by 35 times, up to a production rate of 2.4 tons quality Mo powder product per day. The system consisted of rotary (stage one) + 18 tube pusher (stage two) system which is superior to a traditional pusher + pusher system from both product quality con-trol and cost saving.
By clicking on "Download With Free Account"
I agree that Vogel Communications Group transmits my data to the above mentioned provider of this offer and that he uses my data for the advertising of his product also by email and telephone. For this purpose he receives my address and contact data, as well as data to prove this consent, which he processes on his own responsibility. You have the right to revoke this consent at any time with effect for the future. If the responsible recipient is located in a country outside the EU, we must inform you that the level of data protection may be lower than in the EU.