Patent ID: 7585404

Claim:
A process for the collection and decomposition of ammonium sulfate, said process comprising the following steps: (a) passing a deoiled spent catalyst slurry to a metals recovery unit, where is combined with an ammonium leach solution, producing a stream comprising water and a ammonium sulfate, a stream comprising a compound composed of Group VIII metals and a stream comprising a compound composed of Group VIB metals; (b) passing the streams comprising metal compounds to a catalyst synthesis unit, where they are combined with an oil, hydrogen sulfide gas, ammonia and a small amount of water to create an active slurry catalyst in oil, the active slurry catalyst in oil comprising ammonium sulfate; (c) passing the active slurry catalyst in oil into a decomposition unit, where it is combined with the stream comprising water and ammonium sulfate from step (a); (d) decomposing the ammonium sulfate in the combined streams of step (c) into hydrogen sulfide gas and ammonia streams which are removed from the decomposition unit; and (e) passing the active slurry catalyst in oil from the decomposition unit to storage or to a hydroprocessing unit.