Synthesis of manganese oxidation catalyst

Abstract

A process is described for the preparation of a manganese complex catalyst having the formula: ##STR1## wherein Mn is manganese in a III or IV oxidation state; X is independently selected from a coordinating or bridging species selected from the group consisting of: H.sub.2 O, O.sub.2.sup.2-, O.sup.2-, OH.sup.-, HO.sub.2.sup.-, SH.sup.-, S.sup.2-, >SO, Cl.sup.-, N.sub.3.sup.-, SCN.sup.-, N.sup.3-, RCOO.sup.-, NH.sub.2.sup.- and NR.sub.3 ; R is a radical selected from the group consisting of H, alkyl and aryl radicals; L is an organic ligand containing at least two nitrogen atoms that coordinate with the Mn; z is an integer ranging from -4 to +4; Y is a monovalent or multivalent counterion leading to charge neutrality; and q is an integer from 1 to 4; the process comprising the steps of: (i) reacting in an aqueous medium a manganese (II) salt with the ligand L to form a manganese coordinated substance, a counterion salt M.sub.z Y.sub.q being present wherein M is selected from the group consisting of metals, ammonium and alkanolammonium ions; (ii) oxidizing the manganese coordinated substance of step (i) with an oxidizing agent; (iii) basifying a reaction mixture containing the oxidized manganese coordinated substance formed in step (ii) to a pH of at least 10.5; and (iv) contacting the basified reaction mixture with a further oxidizing agent to form the manganese complex catalyst.

Dependencies are inferred from the claim text.