Method for the preparation of rhodium containing solutions

Abstract

A method for generating a solution containing rhodium at a concentration of at least 0.01 M and preferably at least 0.20 M, comprising treating solid rhodium iodide or other solid source of rhodium with a reducing agent selected from a source of hydrazine, hydrazine hydrate, hydrazinium salts, organic derivatives of hydrazine, hypophosphorous acid and salts of hypophosphorous acid.

1 . A method for generating a solution containing rhodium at a concentration of at least 0.01 M comprising treating solid rhodium iodide (RhI 3 ) or other solid source of rhodium with a reducing agent selected from a source of hydrazine, hydrazine hydrate, hydrazinium salts, organic derivatives of hydrazine, hypophosphorous acid and salts of hypophosphorous acid.  
     
     
         2 . A method as claimed in    claim 1   , where the solution obtained has a concentration of rhodium of at least 0.20 M.  
     
     
         3 . A method as claimed in    claim 1   , where the solid source of rhodium is rhodium chloride, rhodium bromide, rhodium nitrate, rhodium acetate, rhodium oxide and/or rhodium sulphate.  
     
     
         4 . A method as claimed in    claim 1   , further comprising the addition of a co-solvent selected from water and organic solvents, preferably acetic acid, acetic anhydride, methanol, methyl acetate and mixtures thereof.  
     
     
         5 . Solution containing rhodium at a concentration of at least 0.01 M, preparable by the method as claimed in    claim 1   .  
     
     
         6 . The use of a solution containing rhodium as claimed in    claim 5   , as a catalyst source for the production of acetic acid.  
     
     
         7 . The use of a solution containing rhodium as claimed in    claim 5   , as a catalyst source for the production of acetic anhydride.  
     
     
         8 . The use of a solution containing rhodium as claimed in    claim 5   , as a catalyst source for the production of ethylene diacetate.  
     
     
         9 . The use of the method as claimed in    claim 1   , for the regeneration of rhodium catalyst from industrial plants producing acetic acid and derivatives thereof.  
     
     
         10 . Product obtainable by isolation of a rhodium containing solid from a solution obtained by the method claimed in anyone of the preceding claims  1 - 2 .