Process for selectively recovering a mixture of vanadium, molybdenum and/or tungsten from a deactivated catalyst originating from the treatment of a petroleum hydrocarbon feedstock

摘要

Process for the selective recovery of metals from a deactivated catalyst based on molybdenum and/or tungsten, containing at least one contaminating metal of the vanadium, nickel and iron group. According to this process the catalyst is calcined, is treated with stabilised aqueous hydrogen peroxide, a solution of metal compound is recovered and this solution is heated after an ammonium salt and/or a mixture of an ammonium salt and of a metal salt has been added in order to precipitate selectively vanadium, molybdenum and/or tungsten in the form of metal oxides. Application to the selective recovery of vanadium, molybdenum and/or tungsten from deactivated catalysts originating from the operations of hydrotreatment, hydrocracking and/or catalytic cracking of a petroleum hydrocarbon feedstock.