How to Clean Rust From a Cement Patio
- 1). Mix 1 oz. of trisodium phosphate, or TSP, with 1 cup of water in a bucket. Add 1 cup of an absorbent material, including baby powder, talc, diatomaceous earth or fuller's earth.
- 2). Spread the mixture over the rust stains on your patio using a putty knife or trowel. Apply a 1/4 inch-to-3/8 inch layer of the mixture over the stain, mixing additional buckets as needed.
- 3). Allow the mixture to sit on the concrete for 24 hours to draw the rust stains out of the patio.
- 4). Scrape the mixture off of the patio using a putty knife and set it aside for disposal. Use a stiff scrub brush and water to scrub away any remaining rust spots. Rinse the brush often and allow the cement to dry to check the progress of the stain removal.
- 5). Remove the toughest rust stains from concrete using a commercial rust-removal product. Apply it material directly to the rust stains and allow it to soak into the cement for several minutes. Scrub the stains with your brush, then rinse the area completely with water.
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