Muriatic acid is a strong inorganic acid that is used in many industrial processes. Muriatic acid is also known by its chemical name---hydrochloric acid. The acid is found in many commercial and household products. It is even found in your stomach.

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Toilet bowl cleaner

History

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Table salt

Jabir Ibn Hayyan, a noted Persian alchemist, first discovered muriatic acid in the early ninth century. He created the substance by mixing ordinary table salt (sodium chloride) with vitriol (sulfuric acid). Alchemists used muriatic acid in their search to find the philosopher's stone, a legendary tool reportedly capable of turning metals into gold. European scientists used the acid in their scientific research. During the industrial revolution, muriatic acid was used in a number of chemical processes including the synthesis of plastics and the production of food products, and in leather processing.

Production

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Household cleaners

Large scale production of muriatic acid is integrated with the production of other chlorinated organic compounds such as polyvinyl chloride (PVC). Hydrogen chloride gas is produced as a by-product of chemical reactions, and is then dissolved in water to create hydrochloric acid solution. Muriatic acid is available in several strengths. Industrial grade acid runs around 30 to 34 percent, while solutions meant for household use are typically less than 10 to 12 percent.

Industrial Uses

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Pharmaceuticals

Muriatic acid is used to remove oxide scale from iron and steel before it is extruded or otherwise worked, in a process called steel pickling. The acid is used to neutralize caustic solutions and regulate pH in a wide variety of food production, pharmaceutical and water treatment processes. The acid is used in the production of organic and inorganic compounds. The product is also used to clean (regenerate) ion exchange resins. Muriatic acid is an ingredient in chemical products used for electroplating, surface finishing and cleaning.

Household Uses

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Swimming pool

Muriatic acid can be found in a number of household cleaners ranging from toilet bowl cleaners to rust removers. The acid is very effective at removing scale and stains. The concentrated acid is used to clean concrete, pipes, tile, grout, limestone and other surfaces. Muriatic acid is also used to adjust the pH in swimming pools and spas.

Stomach Acid

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Eating food

The digestive fluid secreted by the human stomach is mostly hydrochloric acid. The acid causes proteins in food to unfold (or denature), allowing the stomach's enzymes to work. Many bacteria cannot survive in the strongly acidic environment, which helps to protect the body from food-borne illness.

Warning

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Wear rubber gloves

Since it is a strong acid, exposure to muriatic can burn eyes, skin and lungs. Always handle acid solutions with great care. Wear the appropriate personal protective equipment such as gloves and safety glasses, and ensure adequate ventilation. Store muriatic acid separately from bases, carbonates and metals, as they may react violently with each other.