To provide a new inexpensive palladium extracting agent which is a low environmental load CHON type extracting agent (an extracting agent composed of carbon, hydrogen, oxygen and nitrogen alone and capable of perfect incineration disposal) and has extraction capacity in a wide nitric-acid concentration range including lower concentration and also to provide an extraction method using it.

Ketones represented by formula [1] (wherein, R1is an alkyl group of 1 to 4 carbon atoms; R2is an alkyl group of 4 to 13 carbon atoms; and the sum total of the carbon atoms of R1and the carbon atoms of R2is ≥7) are dissolved as an extracting agent in an organic solvent and brought into contact with a palladium-containing nitric-acid aqueous solution to extract the palladium in the nitric-acid acid solution into the organic solvent.

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