Salicylic acid is a white, crystalline organic acid widely used in pharmaceuticals, cosmetics, and laboratories, particularly known for its role in treating skin conditions such as acne and psoriasis.
🏭⚗️ Production
Salicylic acid is typically produced industrially via the Kolbe–Schmitt reaction, in which sodium phenoxide reacts with carbon dioxide under heat and pressure to form sodium salicylate, which is then acidified to yield salicylic acid.
🔬 Properties
The chemical formula is C₇H₆O₃ with a molar mass of approximately 138.12 g/mol. Salicylic acid appears as a white to slightly tan crystalline powder, is sparingly soluble in water but soluble in alcohol and ether, and has a melting point of about 158–161 °C. It has both acidic and phenolic functional groups, contributing to its reactivity and biological activity.
🧪 Applications
Salicylic acid is widely used in dermatology for the treatment of acne, dandruff, psoriasis, and warts due to its keratolytic and anti-inflammatory properties. It also serves as a precursor in the synthesis of aspirin (acetylsalicylic acid) and other pharmaceutical products, and is used in laboratories as a reagent and preservative.
⚠️ Safety
Salicylic acid can cause skin and eye irritation and should be used with caution, especially in high concentrations. Ingestion of large amounts may be harmful, leading to symptoms such as nausea, dizziness, or salicylate toxicity. Personal protective equipment should be used during handling, and it should be stored in a cool, dry place away from oxidizers.
