Carbolic Acid Origins & Uses

June 29, 2021
What is Carbolic Acid

Discovered in the mid-19th century, carbolic acid (also known as phenol) is today found in several industries in the Midwest and worldwide, including the production of plastics, dyes, and disinfectants.

What Is Carbolic Acid?

Carbolic acid is an aromatic organic compound in the form of a volatile white crystalline solid. It is mildly acidic and requires careful handling because it can cause chemical burns. Originally extracted from coal tar, carbolic acid is today produced on a large scale (around 7B kilograms per year) from petroleum-derived feedstocks. It is an important industrial commodity that functions as a precursor to many materials and useful compounds used throughout the Midwest: for example, to synthesize plastics and related materials. Moreover, carbolic acid is essential for producing polycarbonates, epoxies, and Bakelite, as well as nylon, detergents, and many pharmaceutical drugs.

What is Carbolic Acid Used For

Two-thirds of the annual production of carbolic acid is related to its conversion to precursors for plastics. This includes its condensation with acetone, which creates bisphenol-A–a key precursor to polycarbonates and epoxide resins. But even more prevalent is the condensation of carbolic acid with formaldehyde, which produces phenolic resins–the most famous example of which is Bakelite. Partial hydrogenation of carbolic acid also generates cyclohexanone, a precursor to nylon.

How Carbolic Acid is Used Throughout the US

Carbolic acid is also a versatile precursor to a large collection of drugs, most notably aspirin as well as many pharmaceutical drugs and herbicides. Additionally, carbolic acid is a notable component in the liquid-liquid phenol-chloroform extraction technique that’s used in molecular biology for obtaining nucleic acids from tissues or cell culture samples. Depending on the pH of the solution, either DNA or RNA can be extracted.


Phenol was once widely used as an antiseptic, and from the 1900s to the 1970s it was a common component in the production of carbolic soap. Since 1945, concentrated forms of carbolic acid have become prominent in the permanent treatment of ingrown toe and fingernails–in fact, over the last few decades carbolic acid has been the chemical of choice for podiatrists. Also, many of the sprays used to treat a sore throat (pharyngitis) count carbolic acid as an active ingredient–this includes oral analgesics such as Chloraseptic spray, TCP, and Carmex.


Carbolic acid’s inexpensive cost makes it a great choice for small-scale usage applications, many of which are familiar to our instrument manufacturing company. For example, carbolic acid is included in the industrial paint strippers used in the aviation industry for the removal of epoxy, polyurethane, and other chemically resistant coatings. In the cosmetics industry, carbolic acid derivatives have been used in the creation of sunscreen, hair coloring, skin lightening preparation, and skin toners/exfoliators.

Chemical Compatibility Database

Mid-West Instrument has an extensive online database that allows you to match chemicals with the right materials.   Click this link to use our database

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