Effect of spent catalyst, obtained from the catalytic cracking of petroleum, on the compressive strength of concrete

This study looks at the possibility of using spent catalyst (SC) a by-product of the residual fluid catalytic cracking unit of Tema Oil Refinery (TOR) in Ghana as a pozzolana in the production of concrete for structural or aesthetic use and the optimum ratip of cement/SC, which produces acceptable strengths.

The SC currently poses environmental nuisance and health hazard due to its powdery nature and its possible contamination to ground water since it contains heavy metals (Chromium and Zinc).

The use of the spent catalyst in structural concrete was investigated by designing concrete of design strength 40 N/mm² and varying the proportions of cement, SC and hydrated Lime, making up the binder, whilst keeping water to binder ratio and the proportions of coarse and fineaggregates constant. Compressive strength tests performed on test cubes of each mixture confirmed that SC can be used as a pozzolana in structural concrete as a safe disposal method.

The future use of SC as a cement replacement in the concrete industry looks bright but more work has to be done to determine the durability characteristics of concretes made with SC replacements.