Method of recovering a catalytic metal
AssigneeMitsubishi Gas Chemical Company, Inc.
InventorsTakashi Suzuki, Kouichi Kitahara, Tomiyoshi Furuta, Sadao Nozaki
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Abstract
A method of recovering a catalytic cobalt and/or manganese from a distillation residue in a process for preparing an aromatic carboxylic acid comprising a liquid-phase oxidation of the aromatic hydrocarbon having aliphatic substituent(s) or its oxidized derivatives in the presence of the catalytic cobalt and/or manganese and the distillation of the reaction product, which comprises successively or simultaneously treating the distillation residue with water and with an organic solvent having a relative dielectric constant D of 3.0.ltoreq.D.ltoreq.35
Claims9
A method of recovering catalytic cobalt and/or manganese from a distillation residue obtained in a process for preparing (1) phthalic anhydride from o-xylene, (2) trimellitic anhydride from pseudocumene or dimethylbenzaldehyde, or (3) pyromellitic anhydride from durene, by a liquid phase oxidation in the presence of catalytic cobalt and/or manganese and distillation of the crude oxidation product, said method comprising successively or simultaneously subjecting said distillation residue to a hydration treatment with water to form a residue containing said cobalt and/or manganese and washing said residue with an organic solvent having a relative dielectric constant D of
- 3.0.ltoreq.D.ltoreq.35
- and selected from the group consisting of ketones, esters, ethers, aldehydes, a mixture of acetic acid and pseudocumene, and a mixture of dimethylformamide and pseudocumene and recovering said catalytic cobalt and/or manganese from said residue.
Dependencies are inferred from the claim text.