Black shoe polish contains dyes and oils that can permanently leave behind unsightly stains on your carpet. In order to remove the shoe polish, you will need to use a proper cleaning method. The stain needs to be treated to remove the oil before you can remove the dye from the carpet fibres. After you treat the stain properly, you can salvage your carpet instead of replacing it.
Allow the shoe polish to harden. Scrape dried black shoe polish off the carpet with a butter knife. Loosen any hardened shoe polish, but do not scrape too hard or you will pull out carpet fibres.
Apply a dry-cleaning solvent to the stain with a washcloth. Blot the solvent onto the shoe polish to cover it completely.
Place 2 tbsp of liquid ammonia into a bucket. Add 1 1/2 cups of warm water and 1 tbsp of a liquid dish detergent. Stir the ingredients to mix them well.
Soak a new washcloth into the bucket. Wring out any excess solution, and then blot the black shoe polish stain to soak the area with the solution.
Soak another washcloth in cool water, and wring out any excess water. Blot the stain to rinse the area and to remove the solvent and cleaning solution.
Keep applying the cleaning solvent and solution to the carpet until you remove the stain. You may have to repeat the cleaning process several times, depending on the severity of the stain.
Allow the carpet to air dry. You can speed up the drying process with fan or hair dryer. Use the cool setting on the hair dryer because the heat can cause any lingering shoe polish that you may not notice to become a permanent stain on your carpet.