摘要 |
A process for recovering a solution of Co and Mn acetates and other valuable components of a waste residue of used catalyst discharged from a plant for the liquid-phase, homogeneously catalyzed oxidation of alkylaromatic compounds, to produce polycarboxylic aromatic acids. The residue is pyrolized in a reaction zone provided forming molten metal in an electric arc or molten metal furnace under conditions which convert essentially all carbon in the residue mainly to CO, hydrogen and compounds vaporized in an effluent from the reaction zone. The effluent is passed through a liquid-gas-contacting means to yield a quench or scrubber stream. The residue may also be sludge from a pond in which the residue is stored. The alloy recovered is atomized to form a powder metal which is then digested in acetic acid, and/or aqueous hydrogen bromide, and/or mixtures thereof with the quench or scrubber stream, to form the corresponding salts. In addition to Mn and bromine (Br) values from the effluent, these values may also be recovered from the slag, if desired. Substantially pure Co may be recovered and exported, particularly if earthy residue from a sludge pond is processed to benefit the environment.
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