Trichloroacetic acid is a colorless to white crystalline organic acid used as a strong acid reagent in organic synthesis, as a protein‑precipitating agent in biochemistry, and in controlled medical/cosmetic procedures such as chemical peels (performed by qualified professionals).
🏭⚗️ Production
Trichloroacetic acid (TCA) is produced industrially by exhaustive chlorination of acetic acid or its derivatives (for example by chlorination of acetic acid or oxidation/chlorination routes) to replace hydrogen atoms on the methyl group with chlorine, followed by purification and crystallization to yield solid C₂HCl₃O₂.
🔬 Properties
The chemical formula is C₂HCl₃O₂ with a molar mass of approximately 163.39 g/mol. It appears as colorless to white crystalline flakes or powder that is highly soluble in water and miscible with many organic solvents; it is a strong acid (pKa ≈ 0.7) and is a much stronger acid than acetic acid due to the electron‑withdrawing effect of the three chlorine atoms. TCA is stable under normal storage conditions but decomposes on strong heating and can hydrolyze under certain conditions.
🧪 Applications
Trichloroacetic acid is used in laboratories as a protein precipitant for biochemical assays and sample preparation, as a reagent in organic synthesis (for introduction/removal of certain protecting groups and for acid‑catalyzed reactions), and in dermatology/cosmetic medicine for medium‑ to deep‑depth chemical peels and treatment of some skin lesions when applied by trained professionals; historically it has had uses in vegetation control and other industrial applications.
⚠️ Safety
Trichloroacetic acid is corrosive and can cause severe burns to skin and eyes and damage to mucous membranes; inhalation of dust or vapors can irritate the respiratory tract, and ingestion is harmful. It should be handled with appropriate PPE (acid‑resistant gloves, eye/face protection, lab coat, and where needed respiratory protection) in a well‑ventilated area or fume hood. Store tightly closed in a cool, dry, well‑ventilated place away from bases, strong oxidizers, and reactive metals; follow applicable regulations for disposal and avoid release to the environment because it is toxic to aquatic organisms. Do not use cosmetic/medical concentrations except under qualified professional supervision. Consult the SDS for emergency measures and first aid.
