Process for the rejuvenation of a catalyst comprising a metal from group VIII, a metal from group VIb and an oxide support not comprising zeolite, comprising the following stages: a) said catalyst is regenerated at a temperature of between 360 C. and less than 420 C. so as to obtain a regenerated catalyst comprising a certain content of carbon and sulfur and a proportion of crystalline phase determined by X-ray diffraction and characterized by a ratio of less than 0.6, b) said regenerated catalyst is brought into contact with an aqueous solution consisting of water, of phosphoric acid and of an organic acid having each acidity constant pK.sub.a greater than 1.5, c) drying is carried out at a temperature of less than 200 C.

Process for the rejuvenation of a catalyst comprising a metal from group VIII, a metal from group VIb and an oxide support not comprising zeolite, comprising the following stages: a) said catalyst is regenerated at a temperature of between 360 C. and less than 420 C. so as to obtain a regenerated catalyst comprising a certain content of carbon and sulfur and a proportion of crystalline phase determined by X-ray diffraction and characterized by a ratio of less than 0.6, b) said regenerated catalyst is brought into contact with an aqueous solution consisting of water, of phosphoric acid and of an organic acid having each acidity constant pK.sub.a greater than 1.5, c) drying is carried out at a temperature of less than 200 C.

A method for decontaminating refinery equipment. In one embodiment, the method comprises injecting a chemistry into a feed line of a refinery system unit at a low-pressure region via reciprocating drum pumps, wherein the low-pressure region is upstream of a reactor circuit of the refinery system unit. Further the method comprises allowing the chemistry to flow as a liquid through the feed line of the refinery system unit to be joined by a hydrogen stream that takes up, vaporizes, and carries the chemistry to the reactor circuit to thereby remove contaminants from equipment in the reactor circuit.

A method for decontaminating refinery equipment. In one embodiment, the method comprises injecting a chemistry into a feed line of a refinery system unit at a low-pressure region via reciprocating drum pumps, wherein the low-pressure region is upstream of a reactor circuit of the refinery system unit. Further the method comprises allowing the chemistry to flow as a liquid through the feed line of the refinery system unit to be joined by a hydrogen stream that takes up, vaporizes, and carries the chemistry to the reactor circuit to thereby remove contaminants from equipment in the reactor circuit.