How to Use Citric Acid to Clean Metal

Using acid to remove rust must be a carefully planned process.
Solutions of acid and water can be used to remove rust.Solutions of acid and water can be used to remove rust.
The concentration of the acid must be suited to the task, with a light concentration being used for lightly rusted pieces and a heavier concentration for items severely coated with rust. Careful attention should be paid to the process to ensure your safety and that the article is cleaned properly. Citric acid is one of several acids that can be used for acid solution rust removal. Available as a powder, citric acid is easy to use, although it is one of the weaker acids suitable for this process.

Step 1

Mix the acid/water solution, adding the acid to the water. Using hot or warm water will help speed the chemical reaction. One-quarter cup citric acid to one gallon of water results in a light concentration suitable for lightly rusted articles.

Step 2

Prepare a solution of one-gallon warm water and one-quarter cup baking soda.

Step 3

Clean the rust covered item thoroughly, removing any grease, oil or paint.

Step 4

Place the article into the acid solution and watch for bubbles to start rising, indicating that the chemical process is working.

Step 5

Remove the article from the acid bath and, while rinsing under clear water, use a brush or scouring pad to remove the rust and dirt. Return to the acid bath if necessary.

Step 6

Submerge the rust free article in the solution of water and baking soda to neutralize any remaining acid. Rinse again under clean running water.

Step 7

Dry the item thoroughly.

Things You Will Need

  • Eye protection
  • Gloves
  • 2 buckets
  • Water
  • Soft brush or soft cleaning pad
  • Baking soda

About the Author

Diane Stevens' professional experience started in 1970 with a computer programming position. Beginning in 1985, running her own business gave her extensive experience in personal and business finance. Her writing appears on Orbitz's Travel Blog and other websites. Stevens holds a Bachelor of Science in physics from the State University of New York at Albany.