How to convert benzyl alcohol to benzoic acid

How to convert benzyl alcohol to benzoic acid

Benzyl alcohol and benzoic acid are two common compounds in the chemical industry. Benzyl alcohol is widely used in spices, medicine and cosmetics, while benzoic acid has important applications in food preservatives, medicine, dyes and other industries. The conversion of benzyl alcohol to benzoic acid is not only a common organic synthesis process, but also involves the use of oxidation reactions. This article will detail the process of how to convert benzyl alcohol into benzoic acid and its principle.

Benzyl alcohol into benzoic acid basic principle

The core reaction of the conversion of benzyl alcohol to benzoic acid is the oxidation of benzyl alcohol. The benzyl alcohol molecule contains a-CH₂ OH (hydroxymethyl) group, while benzoic acid contains a-COOH (carboxyl) group. Oxidation of benzyl alcohol is actually the process of converting its-CH₂ OH group to-COOH group. Common oxidants include potassium permanganate (KMnOhmer), chromate, hydrogen peroxide, etc.

Commonly used benzyl alcohol oxidation methods

1. potassium permanganate oxidation method

   potassium permanganate is a strong oxidant and is widely used in the oxidation of organic compounds. Benzyl alcohol can be efficiently oxidized to benzoic acid under mild conditions by reacting benzyl alcohol with potassium permanganate. This reaction usually requires water as a solvent and the reaction temperature is controlled at 30-50°C. Potassium permanganate can not only oxidize hydroxyl in benzyl alcohol, but also oxidize other unsaturated or heterocyclic structures into corresponding carboxyl groups, and finally benzoic acid is obtained.

2. chromic acid oxidation method

   chromates, such as sodium chromate (Na₂ Cr₂ O₂) or potassium chromate (K₂ Cr₂ O₂), are also commonly used in the oxidation reaction of benzyl alcohol. Compared with potassium permanganate, the oxidation of chromate is stronger and the reaction conditions are more stringent. Generally, benzyl alcohol reacts with chromate in an acidic solution, which can be efficiently oxidized to benzoic acid. The use of chromate may cause environmental pollution problems, so it is necessary to pay attention to wastewater treatment and resource recovery in industrial applications.

3. hydrogen peroxide oxidation method

   hydrogen peroxide is a mild oxidizing agent and is suitable for oxidizing benzyl alcohol under milder conditions. Unlike potassium permanganate and chromate, the oxidation of hydrogen peroxide usually requires the assistance of a catalyst, such as molybdate or tungstate. This process has mild reaction conditions and can be carried out at relatively low temperatures, making it suitable for temperature-sensitive feedstocks or where fewer by-products are required.

Choosing Oxidant Considerations

In addition to the reaction efficiency, environmental impact, operation difficulty, cost and other factors should be considered when selecting the oxidant for the oxidation of benzyl alcohol to benzoic acid. For example, although potassium permanganate has high reaction efficiency, its residual manganese compounds need to be treated, otherwise it may have a negative impact on the environment. Chromate also has similar environmental problems, so it is gradually replaced by other oxidants. Hydrogen peroxide is favored in some fields with high environmental requirements because of its low toxicity and environmental friendliness.

Benzyl alcohol to benzoic acid industrial applications

The conversion of benzyl alcohol to benzoic acid is widely used in chemical, pharmaceutical and perfume industries. As preservatives, pharmaceutical raw materials and dye intermediates, benzoic acid is in great demand. And benzyl alcohol as its precursor, the conversion process is an important part of industrial production. By optimizing the oxidation reaction conditions, the yield and purity of benzoic acid can be improved, thereby improving the overall production efficiency.

Conclusion

The conversion of benzyl alcohol to benzoic acid is a relatively simple and efficient oxidation process. According to different requirements, different oxidants can be selected for the reaction. In practical applications, the choice of reaction conditions not only affects the yield and reaction speed, but also involves cost control, environmental protection requirements and ease of operation. Therefore, in industrial production, how to choose the appropriate oxidation method will be an important decision-making problem.

Through the introduction of this article, we should have a deeper understanding of "how to convert benzyl alcohol into benzoic acid. It is hoped that in the future industrial production, a more efficient and environmentally friendly conversion process can be achieved through continuous optimization of the process.