Alcohol is taxed by the federal government and regulated by the United States Department of the Treasury under the Alcohol and Tobacco Tax and Trade Bureau. Taxes must be paid on any ethyl alcohol or ethanol with a proof of 190 degrees or more after it is distilled. Alcohol is denatured to remove the liquid from federal taxation requirements, and also to prevent its use as an illicit source of drinkable alcohol.
Specially Denatured Alcohol
Specially denatured alcohol, also called SDA, results from taking ethanol at either 200-proof or 190-proof strength and adding an ingredient that renders it no longer suitable for consumption. Such combinations include mixing methanol with either denatonium benzoate or methyl isobutyl ketone, also known as MIBK. Toluene or heptane are used to create another special mix. Additional alternatives for making this type of denatured alcohol include methanol, isopropyl alcohol, ethyl acetate, essential oils, diethyl phthalate, tert-butyl alcohol or brucine sulfate. Specially denatured alcohol is used in the cosmetics and pharmaceutical industries, and also in chemical manufacturing.
Completely Denatured
Completely denatured alcohol, known in the industry as CDA, is created by the addition of palox, specsol or methanol to pure 190- or 200-proof denatured alcohol. The goal of this alcohol is to remove any trace of consumable alcohol from the mixture. The exact formulas for CDA are determined by the manufacturer and vary with each company. The resulting mixture so completely denatures the alcohol that the pure alcohol cannot be separated back out from the blend. Denatured alcohol is used in a variety of products, including antiseptics.
Reagent Alcohol
Reagent alcohol also uses 190- or 200-proof denatured alcohol as a base, then adds 5-percent methanol and 5-percent isopropyl alcohol to the mix. This mixture, however, is sometimes sold with only the isopropyl alcohol component. The Medical Chemical Corporation reports that reagent alcohol is "a suitable replacement for pure ethanol in almost all laboratory procedures." Reagent alcohol is used in pharmaceutical applications and in the creation of alcohol standards, the organization adds.
Registration and Licensure
The U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives regulates the sale and use of all types of denatured alcohol. Laboratories and manufacturers must be approved prior to sale, and strict record-keeping is required to account for the exact amounts used in medical experiments or in manufacturing. Federal laws specify a minimum formulation for denaturing alcohol, and products must be tested to ensure these standards are met. More then 20 denaturing formulas are incorporated into federal law. Their use depends on the authorization and the purpose of the product. Solvents and cosmetics, for instance, employ differing formulas.
References
- Warner Graham Company: Alcohol
- Warner Graham Company: Specially and Completely Denatured Alcohol
- Alcohol and Tobacco Tax and Trade Bureau: Information for Tax-free Alcohol Applicants
- Medical Chemical Corporation: What is Reagent Alcohol?"
- National Archives & Records Administration: Formulas for Denatured Alcohol
