To remove oil from concrete, mix an absorbent material with trisodium phosphate, or TSP, spread this mix onto the oil, and allow it to sit until dry. Repeat this process until the oil is gone.
- Choose an absorbent material
Select one of several absorbent materials, such as baby powder or powdered talc for small stains. For larger stains, choose bulk absorbent materials such as diatomaceous earth or Fuller's earth. Choose kitty litter if you are willing to crush it into a finer substance to make a good paste.
- Mix TSP and absorbent material with water
Don eye protection and gloves, then mix 1 ounce of TSP with 1 cup of water. Stir, then mix in about 1 cup of your chosen absorbent material. Stir until a paste forms. Add more water or absorbent material if necessary to get a good consistency.
- Spread the paste on the concrete
Dip a putty knife into the paste, and spread it thickly onto the oil stain. Be certain to cover the entire stain. Make additional paste if necessary.
- Let the paste sit undisturbed
Cover the area to allow the paste to sit without being disturbed, especially by pets or children. Let it dry completely.
- Remove the dried paste
Scrape up the used paste. Scrub the area with a nylon brush if desired. Avoid using metal because it might cause rust spots.
- Repeat as needed
Repeat the entire process if the oil is still present.