RECOVERY AND RECYCLE OF MOLYBDENUM VALUES FROM COAL RESIDUE

摘要

The residue form a Mo-catalyzed coal liquefaction process is treated to recover the Mo in a form in which the Mo can easily be recycled and reused as a catalyst for coal liquifaction. The process includes intimately mixing the residue with alkali in excess of the stoichiometric amount required for water-soluble molybdate formation, subjecting the mixture to an oxidative roast at about 600 DEG C to about 800 DEG C for up to about one hour, leaching the roasted product with water to extract Mo values into solution, and then carrying out a series of steps involving acidifying and ammoniating the solution to form a Mo-bearing precipitate which is recovered and dissolved in aqueous ammonium hydroxide to form a solution which can be applied to coal to catalyze coal liquefaction.