Molybdenum recovery as alloying agent from waste molybdenum solution

Abstract

The present work reports the commercialization of a recycling process of spent acid from filament tungsten wire plant to recover molybdenum (VI)-oxide and further utilizing this product for alloying cast iron. First part of the process consists of ammonia gas neutralization of spent acid containing molybdenum, crystallization and filtration of ammonium molybdate, drying and roasting to produce a commercial grade molybdic-trioxide powder (molybdenum mass fraction 59.2 mas%). Second part of the process consists of grey cast alloying with MoO3 in inducing furnace. Final product was hardened iron alloy with high yield of molybdenum recovery (up to 86 %).