High-Performance Ozone Catalytic Material Made from Spent FCC Catalyst

Fluid catalytic cracking (FCC) catalyst is a porous molecular material widely used in refining. Its active component is usually a Y-type zeolite molecular sieve with a regular crystal structure and a uniform pore-size distribution, which enables shape-selective catalysis based on molecular size. However, the spent catalyst formed as activity declines contains heavy metals such as nickel and vanadium and is listed as HW50 in China's National Catalogue of Hazardous Wastes: it is a toxic industrial waste that must not be disposed of improperly. Stable solidification of these heavy metals and resource utilisation of the spent catalyst have therefore become key research topics.

SINOKLE recognised the potential value of spent FCC catalyst. Making full use of the high specific surface area and excellent adsorption performance of its zeolite framework, the company loaded rare-earth, nickel and vanadium components with ozone-catalytic activity and, combined with its in-house ozone catalytic oxidation technology, successfully produced a high-performance heterogeneous ozone catalytic material using spent catalyst as the main raw material.

The material uses several transition metals (including some precious metals) as active components and, after systematic engineering tests and ratio optimisation, forms a composite system with high adaptability and catalytic activity. Multi-stage precisely controlled sintering is used in manufacture to preserve activity while significantly improving structural stability and suppressing leaching of active components during service, avoiding the risk of secondary pollution. Special pore-structure engineering gives the material a high specific surface area and excellent mechanical strength, extending service life. The support surface is super-hydrophilic, which effectively prevents fouling deposits and pore blockage and keeps the unit running stably over the long term.

The material markedly promotes the decomposition of ozone in the aqueous phase and raises the concentration of hydroxyl radicals (·OH), thereby enhancing oxidation performance; oxidation efficiency is 2 to 5 times higher than with ozone alone. The catalytic mechanism follows three main pathways:

(1) Organic compounds are adsorbed on the catalyst surface and decomposed by ozone or other active species.

(2) Ozone and organic compounds attach to the catalyst surface, interact there to form complexes, and are converted by oxidation into intermediates that desorb into solution and are further oxidised by ozone or reactive oxygen species.

(3) The catalyst first adsorbs ozone and decomposes it into reactive oxygen species, which then attack the organic compounds in solution or on the catalyst surface.

Conventional ozone water treatment is simple and produces no secondary pollution, but ozone utilisation efficiency is relatively low. SINOKLE's innovative ozone catalytic material system improves reaction efficiency and lowers treatment cost while recovering and reusing spent FCC catalyst, offering a technically promising solution for advanced treatment of refractory industrial wastewater.