What to use to clean cabinet knobs that is 20 years old and turning green?

Public Comments

1. If the knobs are metal try the brand OOPS! in the hardware section. Let the knobs soak for 20 minutes or so and scrub them with a hard bristled toothbrush.
2. Silver chloride
3. turning green usually indicates copper. try vinegar and soda
4. First, you need something strong to cut through the grease. You can use the "real" TSP (not TSP substitute) or a de-greaser and clean it with a tooth brush. After you removed all the grease and the knobs are clean, then you can see what type of metal the knobs are made from.. My guess is that the handles had a finished that has worn off. If this is the case the handles will not look good no matter how much you polish them.
5. Can't imagine the rest of this house if the knobs are all corroded.