Porcelain sinks are a common site in homes because of their durability and ease of maintenance. They're usually glazed, which offers some protection, but they can stain easily if not cleaned as soon as spills or messes occur. There are several ways to remove stains from porcelain sinks, including nontoxic alternatives to chemical products. In some cases, bleach and other chemicals may be necessary to completely remove stains and restore a bright, sparkling finish.
Sprinkle baking soda or scouring powder onto the stain and scrub it with a damp cloth or scrub brush. Rinse with clean water. This works as a general cleaner and stain remover.
Spray any stains with 1 part bleach to 4 parts water in a spray bottle. Scrub the stain with a damp cloth or scrub brush and rinse it with clean water. This works well for mold and mildew stains.
Remove soap-scum stains with equal parts white vinegar and warm water. Apply it to the stain and scrub with a scrub brush or nylon scouring pad. Rinse with clean water.
Absorb grease or oil stains with a paste made of scouring powder and water. Stir a small amount of water into the powder until it forms a thick paste and apply it to stain. Allow it to sit overnight, then wipe it with a cloth and rinse. You can also use an all-purpose cleaner or 1 cup of trisodium phosphate in 1 gallon of hot water. Apply it with a cloth and rinse well.
Remove fruit juice or tea stains with 1 tablespoon trisodium phosphate in 1 quart of hot water. Dip a cloth into the solution and wipe the stain. Rinse, then apply 1 tablespoon of bleach mixed with 1 quart of warm water. Wipe it with a cloth and rinse well.
Remove unknown stains with a mixture of whiting (calcium carbonate) and ammonia. Stir ammonia into the whiting until it reaches a thick, peanut-butter consistency. Apply it to the stain and allow it to sit for one hour. Rinse the paste from the sink and wipe it clean with a cloth.