Title: Method for recovering a liquid-phase oxidation catalyst for preparation of terephthalic acid

Abstract: A method for recovering a heavy metal oxidation catalyst used in a liquid-phase oxidation process for producing terephthalic acid from the residue of the reaction mother liquor by stirring the residue together with water in the presence of molecular oxygen and a sulfur compound, subjecting the extracted mixture to a solid-liquid separation to separate the solid impurities, adding the aqueous solution containing the oxidation catalyst to an alkali metal or ammonium carbonate or an aqueous solution of an alkali metal or ammonium carbonate while maintaining the temperature of the system at about 26.degree.C to 70.degree.C, and recovering the heavy metal catalyst as a carbonate precipitate having high purity and good filterability and washability.

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Inventors: Shigeyasu, Motoo (Matsuyama, JA)
Yamazaki, Hatsutaro (Matsue, JA)
Kuki, Michio (Matsuyama, JA)

Application Number: 463025
Filing Date: 1974-04-22
Publication_date: 1976-05-11
Assignee: Matsuyama Petrochemicals Inc. (Osaka, JA)
Primary Class(es): 502/24 423/50, 423/140, 423/144, 562/414
Other Classes:
US Patent Ref:

2964559	Dec, 1960	Burney	260/525.
3033899	May, 1962	Knobloch et al.	260/525.
3105851	Oct, 1963	Knobloch et al.	260/525.
3341470	Sep, 1967	Hensle, Jr.	252/413.
3673154	Jun, 1972	Trevillyah	260/524.
3840641	Oct, 1974	Wampfler et al.	260/525.

Other Refs:
Primary Examiner: Douglas, Winston A.
Assistant Examiner: Konopka, P. E.
Attorney: Sughrue, Rothwell, Mion, Zinn & Macpeak