1-Naphthol-3,6-disulfonic acid Property

Density 

1.816±0.06 g/cm3(Predicted)

pka

-0.14±0.40(Predicted)

CAS DataBase Reference

578-85-8(CAS DataBase Reference)

EPA Substance Registry System

2,7-Naphthalenedisulfonic acid, 4-hydroxy- (578-85-8)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H314Causes severe skin burns and eye damage

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

P321Specific treatment (see … on this label).

P363Wash contaminated clothing before reuse.

P405Store locked up.

P501Dispose of contents/container to..…

1-Naphthol-3,6-disulfonic acid Chemical Properties,Usage,Production

Chemical Properties

Off-white paste. 1-Hydroxynaphthalene-3,6-disulfonic acid [578-85-8]. (4-hydroxynaphthalene-2,7- disulfonic acid), RG acid, Violet acid, C10H8O7S2, Mr 304.3: the free acid ( pKa 8.56) and its alkalimetal salts are readily soluble in water, but the acid sodium salt can be precipitated from concentrated solution with salt. Sulfonation with oleum at 125℃ gives a tetrasulfonic acid, and amination with ammonia and ammonium chloride at 160℃ gives a mixture of 3-amino1-hydroxynaphthalene-6-sulfonic acid and 6- amino-1-hydroxynaphthalene-3-sulfonic acid. Alkali fusion at 170℃ gives mainly 1,6-dihydroxynaphthalene-3-sulfonic acid, and at 250℃ yields 1,3,6-trihydroxynaphthalene. Diazo coupling takes place in the 2-position.

Uses

1-Naphthol-3,6-disulfonic acid is mainly used in the manufacture of acid dyes

Production Methods

Naphthalene-1,3,6-trisulfonic acid is heated with 50 % sodium hydroxide at 180 C for 15 h in an autoclave. After dilution with water, the product is salted out as the monosodium salt and purified by washing with brine.