Method of Recovering Molybdenum from Spent Catalysts Containing Iron and Molybdenum Oxides

摘要

1,191,940. Regenerating spent catalysts. SOC. ITALIANA RESINE S.p.A. 17 Oct., 1967 [26 Oct., 1966], No. 47294/67. Heading B1E. [Also in Division C1] Mo is recovered in the form of an aqueous salt solution from an exhausted catalyst containing iron and molybdenum oxides by pulverising the exhausted catalyst and calcining the powder at 350-450‹C. for 15-30 hours, treating the calcinate at 20-40‹C. with excess aqueous ammonia so that the molar ratio of NH 3 to MoO 3 is from 3:1 to 15:1, ageing the reaction mixture for at least 2 hours, separating the liquid phase from solid residue, distilling off ammonia from the liquid phase until the molar ratio of NH 3 to MoO 3 is between 0.9:1 and 1:1 to 1, and using the aqueous molybdenum salt to prepare fresh Mo-Fe catalyst. Additionally the catalysts may contain Ni and Co.