NOVELTY - Mercaptans contained in hydrocarbons are removed by contacting a hydrocarbon or a mixture of hydrocarbons containing mercaptan(s) with a system comprising trivalent iron, a heteropolyacid having redox properties or partially salified with an alkaline metal or with ammonium, and optionally water; and oxidizing the mercaptans to the corresponding (di)sulfides by the oxidizing effect of the trivalent iron that is reduced to bivalent iron.    USE - The process is used for the removal, by oxidation, of mercaptans contained in hydrocarbon fractions, e.g. fuels, kerosene, or diesel fuel.    ADVANTAGE - The presence of the hetero-polyacid in solution allows an easy, complete, and rapid re-oxidization of the reduced solution of iron salts, which in the absence of the hetero-polyacid are only partially re-oxidized by the air or oxygen and with extremely slow kinetics. It is possible to effect the oxidation reaction of mercaptans, to the corresponding disulfides, in an acid environment, with a solution of trivalent iron and in the presence of a modest quantity of a heteropolyacid having redox properties. Iron is capable of effectively oxidizing the mercaptan to sulfide and can be easily reoxidized by the oxygen of air, due to the presence of the heteropolyacid. The aqueous iron solution and the heteropolyacid can be conveniently recycled and used for different subsequent reaction/regeneration cycles.    DETAILED DESCRIPTION - Removal, by oxidation, of mercaptans contained in hydrocarbons involves:    (A) putting a hydrocarbon or a mixture of hydrocarbons containing mercaptan(s) of formula R-SH, in contact with a system comprising trivalent iron, a heteropolyacid having redox properties or partially salified with an alkaline metal or with ammonium, and optionally water;    (B) oxidizing the mercaptans to the corresponding (di)sulfides by the oxidizing effect of the trivalent iron that is reduced to bivalent iron;    (C) separating the optional aqueous phase from the organic phase;    (D) reoxidizing the bivalent iron to trivalent iron with a gaseous stream containing oxygen; and    (E) recycling the system comprising trivalent iron, heteropolyacid, and optionally water to the oxidation step.    The hetero-polyacid is of formula HnX VyM(12-y)O40 (I) or Hn' Me M12 O40 (II).    R=1-50C aliphatic or 6-30C aromatic hydrocarbon;    n=3-6 and x+y;    X=P, Si, As, B, Ge;    y=1-3;    n'=2-7;    Me=Fe, Co, Mn, Cu; and    M=Mo or W.