Novel method for preventing pollution of used purification catalyst and complete recovery of various metal components of the catalyst

摘要

Process for antipollution treatment and recovery of the metals from a refining catalyst in the spent state, containing at least one contaminating metal chosen from the group consisting of vanadium, nickel and iron. The process of the invention is characterised especially in that: a) the catalyst discharged from the industrial unit is subjected to a stripping operation; b) the stripped catalyst is calcined under critical conditions; c) the calcined catalyst is subjected to a heat treatment in the presence of an alkaline base in the molten state; d) the solid mass resulting from stage c) is treated with water. The process applies to an antipollution treatment and the recovery of the metals from spent catalysts especially from catalysts for hydrotreatment or hydroconversion of an oil feedstock.