PURPOSE: To recover the catalytic activity of Pd catalysts for wet oxidation of waste water contg. COD components, suspended solids, ammonia, etc. and to regenerate said catalysts in the stage of regenerating said catalysts by treating the catalysts with aq. solns. contg. phosphoric acid and specific org. acids.
CONSTITUTION: Pd or compds of Pd insoluble or hard to dissolve in water are used as catalysts to be used for treatment of waste water contg. COD components, suspended solids or further ammonia, etc. whereby the waste water is subjected to wet oxidation treatments. When the functions of such catalysts decrease, the catalysts are dipped for ≥15min in aq. solns. of 0.1W5.0 normal concn. of phosphoric acid and org. acids (except formic acid and oxalic acid) such as aliphat. carboxylic acids such as acetic acid, lactic acid and tartaric acid, phenolic carboxylic acid and benzoic acid, and arom. carboxylic acids such as phthalic acid and salicylic acid and at ≥40°C, whereby the catalytic activity is recovered and the catalysts are regenerated as catalyst for waste water treatments.
JIYOUDEN NORIO
HARADA YOSHIAKI
YAMAZAKI KENICHI
| JPS5451991A | 1979-04-24 | |||
| JPS5080291A | 1975-06-30 | |||
| JP37016585A |
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