SODIUM SULPHATE

PRODUCT IDENTIFICATION
CAS NO.

7757-82-6 (Anhydrous)
7727-73-3 (Decahydrate)

SODIUM SULPHATE
EINECS NO. 231-820-9
FORMULA

Na2SO4
MOL WT.

142.04

H.S. CODE

 2833.11
TOXICITY  
SYNONYMS Disodium monosulfate; Sulfuric acid, Sodium salt;
Disodium sulfate; Sodium sulfate; Sulfuric acid, sodium salt; Sulfuric acid, Disodium salt;Sulfuric acid disodium salt; Salt cake; Bisodium sulfate; Sodium sulfate (2:1); Thenardite; Natriumsulfat; Trona;
DERIVATION  

CLASSIFICATION

 

PHYSICAL AND CHEMICAL PROPERTIES
PHYSICAL STATE

Hygroscopic white powder, Odorless
MELTING POINT

880 - 888 C
BOILING POINT 1100 C (Decomposes)
SPECIFIC GRAVITY

2.66 - 2.75
SOLUBILITY IN WATER Soluble
pH

Aqueous solution is neutral
VAPOR DENSITY  

AUTOIGNITION

 

NFPA RATINGS

 Health: 1; Flammability: 0; Reactivity: 0

REFRACTIVE INDEX

 
FLASH POINT  
STABILITY Stable under ordinary conditions

GENERAL DESCRIPTION & APPLICATIONS
Sodium sulfate is a white, orthorhombic crystalline solid at room temperatures ( a monoclinic structure at > 100 C, a hexagonal structure at > 250C). It is reduced to sodium sulfide at high temperature. But sodium sulfate is a stable compound which does not decompose and does not react with oxidising or reducing agents at normal temperatures. It is neutral (pH of 7) in water. Sodium sulfate is most soluble in water at 32.4 C (49.7g/100 g). Commercial major source of sodium sulfate is salt cake (impure sodium sulfate), a by-product of hydrochloric acid production from sodium chloride by treatment with sulfuric acid. Sodium sulfate is obtained also as a byproduct of rayon production and sodium dichromate production. The decahydrate is known as Glauber's salt. About half of the world's production is from the natural mineral form of the decahydrate (mirabilite). Anhydrous sodium sulfate is found in nature as the mineral thenardite (Na2SO4). Other sodium sulfate minerals are metasideronatrite Na4Fe2(SO4)4(OH)213H2O, krohnkite Na2Cu(SO4)212H2O, and schairerite Na3(SO4)(F,Cl). Sodium sulfate is consumed in four major categories; powder detergents as a processing aid and as a filler, wood pulp processing for making kraft paper, textile dyeing processes as a levelling agent to penetrate evenly, and molten glass process to remove small air bubbles. Sodium sulfate is employed also as a raw material for the production of various chemicals.
SALES SPECIFICATION

APPEARANCE

white powder
Na2SO4

99.0% min

WATER INSOLUBLES

0.05% max

Mg

0.15% max

Cl

0.35% max

Fe

0.002% max

pH

Neutral to slightly alkaline

MOISTURE

0.2% max

WHITENESS

80% min

PARTICLE SIZE

50% (100 mesh)

TRANSPORTATION
PACKING 25kgs, 50kgs, 1mt in Bag
HAZARD CLASS Not regulated
UN NO.  

OTHER INFORMATION

Sulfate (also spelled sulphate in Europe) is any chemical compound containing the SO42- ion related to sulfuric acid (H2SO4). Sulfates are salts or esters of sulfuric acid, formed by replacing one or both of the hydrogens with a metal or a radical as in sodium sulfate, Na2SO4. Sulfates in which both hydrogens are replaced are called normal sulfates. Bisulfate is a compound that has the HSO4- radical. Bisulfate (called also hydrogen sulfate or acid sulfate) is a compound formed by replacing only one hydrogen in sulfuric acid. Sulfite (also sulphite) is a compound that contain the sulfite ion SO32-. Sulfites are salts or esters of sulfurous acid (H2SO3), formed by replacing one or both of the hydrogens with a metal or a radical as in sodium sulfite, Na2SO3. Sulfites in which both hydrogens are replaced are called normal sulfites. Bisulfite is a compound that has the HSO3- radical. Bisulfate (called also hydrogen sulfite or acid sulfite) is a compound formed by replacing only one hydrogen in sulfurous acid. The term of 'meta' or 'pyro' is the chemical prefix for oxo acid formed through the loss of one water molecule (dehydration) from two molecules of ortho acid by heating. Pyrosulfuric acid is an example ( 2H2SO4 - H2O = H2S2O7). Ortho acid is the compound fully hydrated acid or its salts. Orthophosphoric acid is an example (2·H3PO4 = P2O5.3H2O), in contrast to the less hydrated form, pyrophosphoric acid (2·HPO3 = P2O5.H2O). Na2O5S2 is called sodium metabisulfite (2·HNaO3S - H2O). Sulfide is a compound having one or more sulfur atoms in which the sulfur is connected directly to a carbon, metal, or other nonoxygen atom; for example sodium sulfide, Na2S. Sulfide ion is S2- with oxidation number -2. Bisulfide ion is an anion formed by two sulfur atoms having an overall -2 charge, (S2)2-. Sulfamate is a salt of sulfamic acid (HSO3NH2). Calcium sulfamate Ca(SO3NH2)2 is an example.