What Kind of Acid Is Used to Clean & Brighten Aluminum?

Aluminum is a naturally soft metal first used commercially for the production of cookware. It is an ideal metal for pots and pans because it heats fast and evenly and is lightweight. Aluminum is easy to clean and brighten with mild acids often found in pantries or kitchen cupboards. Other acidic aqueous cleaning solutions are also effective, but they are much harsher and not as safe.

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Aluminum is soft enough to be easily bent into cookware pieces.

Uses For Aluminum

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Aluminum is widely using to process or preserve food.

In addition to its use in cookware, aluminum is also used for food processing and storage because it is easily cleaned with steam, is resistant to fatty acids and is splinter-proof. The food industry uses food processing equipment such as vats and piping that are made of aluminum. Aluminum foil is used to prevent partially prepared or frozen foods from going rancid or spoiling. Aluminum is widely used in medicine such as antacids and elsewhere in the pharmaceutical industry. Elsewhere in food processing, aluminum is used in everything from sugar, beer, flour, gelatin, meats, frozen foods and dairy products, to being an agent in baking powder. Alum helps preserve the color and firmness of fruits.

Mild Household Acids

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Ordinary household vinegar is an effective cleaning acid.

Dark stains that form on aluminum are very easy to remove from cookware by adding 1 tbsp. of vinegar to 1 qt. of water and adding the liquid to the discolored aluminum pan and boiling until the pan is clean. To remove lime scale with vinegar, add equal parts of vinegar and water to the pan and bring it to a boil. Lemon juice also cleans discoloration from aluminum. Cream of tartar or potassium hydrogen tartrate is useful for brightening aluminum. Soak the aluminum pot, pan or utensil in a quart of hot water mixed with 2 tbsp. cream of tartar.

Acidic Aqueous Cleaners

Acidic aqueous cleaning solutions may contain mineral acids such as nitric, sulfuric, phosphoric and hydrofluoric acid. Chromic or organic acids may include acetic and oxalic acids. These products may also contain chelating agents, detergents and small amounts of water-miscible solvents. Acidic aqueous solutions are sometimes used to clean or remove oxide, rust or scale from aluminum.

Safety Precautions

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Use of proper safety attire protects skin and eyes.

Very strong acids are extremely dangerous. Always wear protective safety glasses and gloves when using strong acids. Some acids such as sulfuric acid produce gas when heated and fumes from the gases can be harmful. Sulfuric and hydrofluoric acids are used in toilet bowl cleaners. Oxalic acid is an effective rust remover. Hydrofluoric acid is colorless but pungently odorous and must be used in well-ventilated areas. Always have baking soda on hand when using hydrofluoric acid because it neutralizes spills. Be especially cautious when adding acid to water. Even more importantly, never add water to a strong acid solution.