Surface of the tiles provide the luxury of being easy to clean. This is true of the same tiles, but it is not always the case of grout. Grouting in high traffic areas of a tile surface will be susceptible to stains as soon as the sealant has worn off. A damp cloth normally cleans the colored grout. But for difficult stains you should use something a little more potent. A mixture of nitric acid, hydrogen peroxide and water will clean up almost any stain on the grout, leaving a surface of the tile that looks like it did when it was installed.
Instructions
1 Fill an empty 5 gallon bucket with 3 litres of water. Slowly pour 1 cup of hydrogen peroxide into the water. Gently add 1 cup of nitric acid to the peroxide/water mixture.
2 Remove the lid from a spray bottle. Set the bottle firmly on a flat surface. Slide the small end of a plastic funnel into the bottle. Pour the cleaning mixture into the large end of the funnel to fill the bottle. Be careful not to overfill the bottle and pour the chemicals.
3 Spray the mixture of chemicals in the grout lines between the tiles. Scrub the grout with a brush of nylon bristles. Slide the brush back and forth along the length of each grout line to remove the stain. Immediately clean each grout line with a cloth soaked in clean water.
4 Inspect grout lines for remaining stains. Repeat the process as needed until all the stains are gone and the grout is all of the same color. Clean grout and tiles with a damp cloth to remove any debris. Allow grout to dry thoroughly before proceeding.
5 Squirt grout sealant on each grout line. Let it dry during the night chemical sealing before touching the tile or grout.
Tips and warnings
- Always wear rubber gloves, safety goggles and a dust mask when working with chemicals.
- Hydrogen peroxide and nitric acid are the two hazardous chemicals, especially when mixed in an inadequate manner. Always pour water, peroxide and nitric acid then in that order. Mixing chemical products out of service can create an unstable mixture.
- Never use a mixture containing more than 30 percent hydrogen peroxide or nitric acid. If you do, it will make the mixture extremely dangerous.