Chemical formula: C6H4 (OH) 2
International name: Hydroquinone, 1,4-benzenediol, benzene-1,4-diol
CAS No: 123-31-9
Appearance: Crystals from white to whitish-gray color.
Packing: bags 25 kg
Storage: In a closed container, in covered warehouses equipped with general ventilation.
Hydroquinone - crystalline substance. Soluble in alcohol, acetone, ether. Sparingly soluble in water. Hydroquinone - strong reductant is oxidized at first converted into quinhydrone (charge transfer complex quinone to hydroquinone in the ratio 1: 1) and then p-benzoquinone.
In industry it is used several methods to obtain hydroquinone:
• oxidation of aniline sulfate MnO2 manganese peroxide or H2CrO4 to p-benzoquinone, which is reduced with iron powder in water at 70-80 ° C in the presence of NaHSO3;
• 70% hydroxylation of phenol with hydrogen peroxide at 90 ° C (catalyst - 75% H3PO4 or 65% HClO4). The resulting mixture of hydroquinone and catechol are separated by distillation;
• oxidation of 1,4-diisopropylbenzene with oxygen in the air, followed by acid hydrolysis to hydroquinone and acetone;
• reacting phenol and acetone, followed by oxidation of 4-isopropylphenol formed hydrogen peroxide in an acidic medium to hydroquinone and acetone.
• Hydroquinone - developer in photos (usually in the form of synergistic combinations with metol or fenidonom);
• as an antioxidant for rubber, food, stabilizer for storage of solvents;
• polymerization inhibitor of vinyl monomers;
• raw material in the manufacture of dyes, pharmaceuticals, photographic materials;
• In a quinhydrone is used to determine pH and others.