How to convert sodium benzoate into benzoic acid

The method of making weak acid from strong acid is adopted, and strong acid is added.

Taking concentrated sulfuric acid as an example, the chemical equation is as follows:

C6H5COONa+H2SO4 (concentrated) = =C6H5COOH+NaHSO4

Supplement:

Sodium benzoate (chemical formula: C6H5CO2Na) is the sodium salt of benzoic acid. Sodium benzoate is an acidic preservative, which has good antiseptic effect in acidic environment. It is a very common food preservative, which can prevent deterioration and prolong the shelf life, and is widely used in all countries of the world. However, in recent years, concerns about its toxicity have limited its application, and some countries, such as Japan, have stopped producing sodium benzoate and restricted its use.

Sodium benzoate is mostly white particles, odorless or slightly fragrant, slightly sweet and astringent; Soluble in water (room temperature) 53.0g/ 100ml, PH around; Sodium benzoate is also an acidic preservative, which has no bactericidal or bacteriostatic effect in alkaline medium. The best preservative PH is 2.5-4.0, and the bactericidal effect of 5% solution is not very good at PH5.0. Sodium benzoate has strong lipophilicity and easily penetrates the cell membrane and enters the cell body, which interferes with the permeability of the cell membrane and inhibits the absorption of amino acids by the cell membrane. The alkali stored in the ionized and acidified cells inhibits the activity of respiratory enzymes in cells and prevents the condensation reaction of acetyl-CoA, thus achieving the purpose of preserving food.