Preparation
Many carboxylic acids can be obtained from natural sources such as vegetable oils. The preparation of soap from them, an experiment that you could easily carry out at home, involves the preparation and isolation of the sodium salts of long-chain carboxylic acids.
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| Triolein (a triglyceride) | NaOH ⟶ | Glycerin | + | Oleate |
Lipids, triglycerides or fats are triesters of glycerin found both in vegetable oils (olive, sunflower, etc.) and in animal fats (tallow, lard, butter, etc.). These esters break down (hydrolysis) in basic medium. This process is called saponification (from Latin sapo, "soap").
In general, when one saponifies an ester, an alcohol and a carboxylate are produced. In this case the alcohol is 1,2,3-propanetriol (glycerin).
In general, when one saponifies an ester, an alcohol and a carboxylate are produced. In this case the carboxylate is cis-9-octadecenoate (oleate). Its neutralization with mineral acid yields oleic acid, one of the most important and ubiquitous fatty acids.
Industrial methods
Formic and acetic acids are industrially prepared from simple raw materials, some of them obtained from petroleum.
