2-NAPHTHOL-3,6-DISULFONIC ACID DISODIUM SALT

PRODUCT IDENTIFICATION
CAS NO. 135-51-3

2-NAPHTHOL-3,6-DISULFONIC ACID DISODIUM SALT
EINECS NO. 205-196-3
FORMULA C10H6Na2O7S2
MOL WT. 348.25
H.S. CODE

 
TOXICITY

 
SYNONYMS 2-Naphthol-3,6-disulfonic acid disodium salt; R Salt; R acid;
 Dinatrium-3-hydroxynaphthalin-2,7-disulfonat; 3-Hidroxinaftaleno-2,7-disulfonato de disodio; 3-Hydroxynaphtalène-2,7-disulfonate de disodium; Disodium 2-naphthol-3,6-disulfonate; 3-Hydroxynaphthalene-2,7-disulfonic acid Disodium salt; Disodium 3-hydroxynaphthalene- 2,7-disulphonate;
SMILES

 

CLASSIFICATION

 

PHYSICAL AND CHEMICAL PROPERTIES
PHYSICAL STATE White to gray-yellow powder
MELTING POINT

107 C
BOILING POINT  
SPECIFIC GRAVITY

 
SOLUBILITY IN WATER soluble
AUTOIGNITION  
NFPA RATING Health: 1; Flammability: 1; Reactivity: 0
FLASH POINT  
STABILITY Stable under ordinary conditions

APPLICATIONS
Naphthols are either of two crystalline monohydric alcohols, derived from naphthalene and belong to the phenol family. There are position isomers; alpha-naphthol (also called 1-naphthol) is 1-hydroxynaphthalene and beta-naphthol (also called 2-naphthol) is 2-hydroxynaphthalene. The compound 1-naphthol is made by heating 1-naphthalenesulfonic acid with caustic alkali or by heating 1-naphthylamine with water under pressure. The compound 2-naphthol is manufactured by fusing 2-naphthalenesulfonic acid with caustic soda. The different positions provide various chemical structures which offer important roles to each characteristic colours. Naphthols are slightly soluble in water but readily soluble in short alcohols, ethers chlorinated solvents, and caustic alkalis. They are used directly in making several dyes and are converted into numerous corresponding amines, esters, ethers and carboxylic derivatives as well as into numerous sulfo- and nitro-group substituted (mono-, di- and tri) naphthol compounds. They find extensive applications in making dyes, pigments, fluorescent whiteners, tanning agents, antioxidants, and antiseptics. Naphthol structure is found as a ligand in transition-metal catalysts particularly in the form of  binaphthol (binol) which is composed of two naphthol rings connected at one carbon site on each ring. Optically active binol is widely used in asymmetric synthesis of rearrangements, epoxidations, reductions.

Sulfonic acid is a compound with general formula RSO2OH, where R is an aliphatic or aromatic hydrocarbon. It is a derivative of sulfuric acid (HOSO2OH) where an OH has been replaced by a carbon group or a compound where a hydrogen atom has been replaced by treatment with sulfuric acid; for example, benzene is converted to benzenesulfonic acid (water-soluble). Sulfonic acid has a sulfur atom bonded to a carbon atom of a hydrocarbon and bonded also to three oxygen atoms, one of which has been attached to a hydrogen atom. Sulfonic acid is acidic due to the hydrogen atom, stronger than a carboxylic acid. Sulfonic acid is one of the most important organo sulfur compounds in organic synthesis. Sulfonic acids are used as catalysts in esterification, alkylation and condensation reactions. Sulfonates are salts or esters of sulfonic acid. Sulfonic salts are soluble in water. Sulfonic acid and its salts present in organic dyes provide useful function of water solubility and or improve the washfastness of dyes due to their capability of binding more tightly to the fabric.

R-salt (3-Hydroxynaphthalene-2,7-disulfonic acid Disodium salt), an important dye intermediate, is produced from naphthalene by a combination of the unit processes of sulfonation, nitration, reduction, and hydrolysis. R-salt is used in the manufacture of a large number of azo dyes and pigments.
SALES SPECIFICATION

APPEARANCE

 White to gray-yellow powder
CONTENT

60.0% or 80% or 90%

PURITY

99.0%
FREE ACID

1.5% max

MOISTURE

Balance

RELATED SUBSTANCES

1.5% max

Fe

100ppm max
TRANSPORTATION
PACKING 25kgs in Bag
HAZARD CLASS TSCA listed
UN NO.  



OTHER INFORMATION