Object: This invention provides a method of refining an Rh-containing
solution also containing at least one type of impurities of heavy metals,
alkaline earth metals, and Ag.Means for solving the problems: The
invention provides a method of refining an Rh-containing hydrochloric
acid solution also containing Ag and at least one other impurity of heavy
metals and alkaline earth metals, the method comprising the steps of: (a)
adding an alkali to the solution to adjust pH of the solution to 7-12,
whereby generating a neutralized precipitate containing Rh and other
components; (b) filtrating and separating the neutralized precipitate;
(c) adding a first hydrochloric acid for redissolving the neutralized
precipitate in an amount such that the mole ratio of Cl to Rh (mole ratio
Cl/Rh) of a resulting solution becomes 3-4; (d) filtering the resulting
solution to remove Ag as precipitate, and (e) extracting the solution
obtained by the previous step as an aqueous phase with DEHPA.