How to Remove Rust Stains from a Driveway
- 1). Mix 1 ounce of tri-sodium phosphate (TSP) in a gallon of hot water. This chemical can be found at hardware and paint stores. Wet the concrete and use a scrub brush to apply the solution. Scrub vigorously and let the solution soak into the concrete for 10 to 15 minutes. Rinse well.
- 2). Try a product called Iron Out, which is sold in plumbing supply stores.
- 3). Combat really bad stains with a pressure washer and muriatic acid. Apply the acid as directed by the manufacturer, leave it to soak for a few seconds, and follow with a pressure washer set at 2,500-3,000 psi. Sprinkle baking soda over the cleaned area to neutralize the acid and wash again.
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