Modification of petrochemical fluid catalytic cracking catalyst waste properties by treatment in high temperature

Abstract

Approximately 400 000 tons of waste catalysts are produced by petrochemical industry in fluidized bed catalytic cracking (FCC) process annually. In Lithuania (Mažeikiai Oil Refinery) the waste amounts up to about 200 tons/year. As FCC catalyst is an inorganic alumosilica zeolite material, the properties of it are important for refractory concrete. This work investigated properties of the waste fired at temperature of 800-1300 0C. It was established that at temperatures higher than 1050 0C, in the waste FCC catalyst the physical and structural changes take place, the zeolitic structure is destroyed and the mineralogical composition undergoes changes, as well as porosity and size of particles. In case of reuse of catalyst waste in refractory concrete, these changes of material can negatively influenced on properties of refractory concrete. One of the promising directions for reuse of waste in refractory material is its modification at temperature of approximate 1000 0C when the porosity of particles changes and, supposedly, the germs of mullite crystals are forming, irrespective of the still dominating zeolitic structure.