How to Remove Stubborn Oil Stains from Concrete

Concrete acts like a thirsty sponge, drawing oil deep into its porous structure the moment a drip hits the surface. Once the oil penetrates past the top layer, simple soap and water won't touch it. You are looking at a chemical battle between the grease trapped in the stone and the solvents designed to break those bonds. Success in this project depends on your patience. If you rush the scrubbing or fail to let the degreaser dwell, the stain will simply bloom back to the surface once the moisture evaporates. When done well, the dark, slick patch will fade to the natural, light grey color of the surrounding concrete, leaving no trace of the leak.

1. Absorb the Surface Oil. If the oil is still wet, pile clay-based cat litter or sawdust over the spill. Leave it for at least 24 hours to draw out as much surface oil as possible, then sweep it up and dispose of it.
2. Break the Bond Fast. Pour a concentrated concrete degreaser directly onto the stain. Use a stiff-bristled synthetic brush to scrub the cleaner into the pores, working in a circular motion until a thick lather forms.
3. Let Chemistry Do Work. Let the degreaser sit undisturbed for 15 to 20 minutes, but do not let it dry completely. If it begins to look chalky, mist it lightly with water to keep the chemical reaction active.
4. Flush It All Away. Rinse the area thoroughly using a pressure washer or a high-pressure garden hose nozzle. Use hot water if available, as it helps keep the grease in a liquid state for easier removal.
5. Extract Oil from Pores. For older, deep-set stains, mix degreaser with an absorbent powder like baking soda or cat litter to form a thick, peanut-butter-like paste. Spread it over the stain and cover it with plastic, sealing the edges with tape.
6. Dust Away All Traces. Leave the sealed poultice for 24 hours. Remove the plastic, let the paste dry completely into a powder, sweep it away, and rinse the floor one final time.