Definitive Assessment of the Level of Risk of Exhausted Catalysts: Characterization of Ni and V Contaminates at the Limit of Detection

The polluting level, the composition and the chemical structure of toxic heavy metals in spent zeolite from the fluid catalytic cracking (FCC) process of refinery, chosen as a model system of exhausted catalysts, have been evaluated through a novel characterization procedure, which combines different X-ray analysis techniques. The developed protocol of analysis has provided an effective tool for the definitive assessment of the level of toxicity and hazardousness of exhausted automotive catalysts, allowing their classification as reusable materials.