Sodium sulfate

Absorption

Absorption of sodium sulfate after ingestion in rats was investigated. 35)S-Radioactivity excreted in urine during 24 hr indicated almost complete absorption from GI tract. Determination in serum 2 hr after admin revealed 3-fold increase in sulfate concentration rapid and almost complete absorption of inorganic sulfate occurs after oral admin in rats.

Description

Anhydrous sodium sulfate (Na2SO4) is typically used in organic chemistry as a drying agent. After aqueous extractions the organic layer always has a certain amount of water left in it. Adding anhydrous sodium sulfate removes this water by forming the sodium sulfate hydrate, which conveniently is also a solid allowing it to be filtered away. Magnesium sulfate (MgSO4) is a similar drying agent.

Chemical properties

Sodium sulfate, NaS04, also known as thenardite and salt cake, is a crystalline compound that melts at 888°C (1632°C). Sodium sulfate is found in natural form(thenardite) in Chile and Spain. It is used in the manufacture of paperboard, glass,and freezing mixtures. The hydrate, Na2S04·10H20, also known as "Glauber's salt," is a white water-soluble solid formed by heating sodium chloride and sulfuric acid. It is used in dyeing,manufacturing glass,and in the preparation of sodium bisulfate.

Chemical properties

Sodium sulfate is a white crystalline solid. It frequently is found as the decahydrate

Physical properties

Anhydrous sodium sulfate is a white crystalline powder; orthorhombic or hexagonal structure; hygroscopic; refractive index 1.468; hardness 2.8 Mohs; density 2.664 g/cm³; melts at 884°C; soluble in water, insoluble in ethanol.
The decahydrate consists of colorless monoclinic crystals; refractive index 1.394; hardness 1.8 Mohs; density 1.4 6g/cm³; decomposes at 32°C; soluble in water; insoluble in ethanol.

Occurrence

Sodium sulfate occurs in nature as the minerals mirabilite and thenardite. While thenardite is the anhydrous form of Na²SO⁴, mirabilite is a naturallyoccurring decahydrate, Na₂SO₄?10H₂O.
Sodium sulfate is one of the most important sodium salts. The decahydrate,commonly known as the Glauber’s salt, was first prepared by Johann Glauber in the seventeenth century as a by-product in making hydrochloric acid from sulfuric acid and sodium chloride.
Sodium sulfate is used in manufacturing paper pulp by the Kraft Process. Other uses are in manufacturing glass and ultramarine; in dyeing and printing textiles; as a filler in synthetic detergents; and for standardizing dyes. A major use of anhydrous sodium sulfate is as an agent to remove water from organic solvents and their extracts for organic synthesis and instrumental analysis. Sodium sulfate is a common laboratory reagent. Also, it is used to prepare other sodium salts.

The Uses of Sodium sulfate

To a  solution of the SM (70 g, 386 mmol)  in AcOH (100 mL) and absolute EtOH (400 mL) was slowly added iron powder (40 g). The reaction was cooled  in an ice-H2O bath and treated with conc. HCl (1 mL). The addition was exothermic. The reaction was heated  to reflux for 20 min, after which time it was allowed to cool to room temperature. The  mixture was filtered and the filtrate concentrated to a thick oil. The  resulting oil was partitioned between EtOAc (500 mL) and H2O (200  mL) and basified to pH 10 using 6N NaOH. The mixture was filtered through  celite. The org layer was separated and washed with sat aq NaHCO3 (2  x 100 mL), H2O (2 x 100 mL), brine (100 mL), dried (Na2SO4),  and concentrated to provide the product. [37.2 g, 64%]

The Uses of Sodium sulfate

Used in kjeldahl nitrogen determination; drying agent .

The Uses of Sodium sulfate

Sodium sulfate is a filler in the manufacturing of synthetic detergents and soaps and a laboratory reagent. It may enhance the irritant action of certain detergents.

The Uses of Sodium sulfate

Sodium Sulfate is the salt of sulfuric acid that is readily soluble in water and exists as crystals or crystalline powder. it is used in cara- mel production.

Background

Sodium Sulfate Anhydrous is the anhydrous, sodium salt form of sulfuric acid. Sodium sulfate anhydrous disassociates in water to provide sodium ions and sulfate ions. Sodium ion is the principal cation of the extracellular fluid and plays a large part in the therapy of fluid and electrolyte disturbances. Sodium sulfate anhydrous is an electrolyte replenisher and is used in isosmotic solutions so that administration does not disturb normal electrolyte balance and does not lead to absorption or excretion of water and ions.

Indications

indicated for bowel cleansing prior to colonoscopy or barium enema X-ray examination.

Definition

A white crystalline compound, Na₂SO₄, usually known as the anhydrous compound (orthorhombic; r.d. 2.67; m.p. 888°C) or the decahydrate (monoclinic; r.d. 1.46; which loses water at 100°C). The decahydrate is known as Glauber’s salt. A metastable heptahydrate (Na₂SO₄·7H₂O) also exists. All forms are soluble in water, dissolving to give a neutral solution. The compound occurs naturally as
mirabilite (Na₂SO_4·10H₂O),
threnardite (Na₂SO₄), and
glauberite (Na₂SO₄·CaSO₄).
Sodium sulphate may be produced industrially by the reaction of magnesium sulphate with sodium chloride in solution followed by crystallization, or by the reaction of concentrated sulphuric acid with solid sodium chloride. The latter method was used in the Leblanc process for the production of alkali and has given the name salt cake to impure industrial sodium sulphate. Sodium sulphate is used in the manufacture of glass and soft glazes and in dyeing to promote an even finish. It also finds medicinal application as a purgative and in commercial aperient salts.

Production Methods

Sodium sulfate is mined from its natural mineral deposits and subjected to purification.
Sodium sulfate is synthesized by the Mannheim process or Hargreaves process. Manheim’s process is based on Glauber’s reaction between sulfuric acid and sodium chloride: 2NaCl + H₂SO₄ → Na₂SO₄ + 2HCl↑
The process was devised by Johann Glauber to produce hydrochloric acid. Sodium sulfate is isolated from the solution by fractional crystallization.
Hargreaves’ process also was developed to produce hydrochloric acid. It is a variation of Mannheim’s method. In this method, sulfur dioxide is used instead of sulfuric acid. The reaction is as follows: 4NaCl + 2SO₂ + O₂ + 2H₂O → 2Na₂SO₄ + 4HCl↑
Sodium sulfate also is obtained as a byproduct of manufacturing phenol by caustic fusion.

General Description

Sodium sulfate (Na₂SO₄) can be obtained directly via precipitation from a saturated solution of Na₂SO₄ at room temperature (20°C). Its crystallization and growth rates at room temperature (20°C) under various conditions have been investigated. Sodium sulfate can be produced during Leblanc process, from sodium chloride and sulfuric acid.

Flammability and Explosibility

Non flammable

Pharmacokinetics

Induces catharsis by the osmotic effects of the unabsorbed sulfate salts and polyethylene glycol (PEG) in the GI tract. Specifically, sulfate salts provide sulfate anions, which are poorly absorbed, and PEG, which is primarily unabsorbed, causes water to be retained in the GI tract resulting in watery diarrhea.

Safety Profile

Moderately toxic by intravenous route. Mildly toxic by ingestion. An experimental teratogen. Experimental reproductive effects. Questionable carcinogen with experimental tumorigenic effects. Violent reaction with Al. When heated to decomposition it emits toxic fumes of SOx and Na2O. See also SULFATES.

Potential Exposure

Sodium sulfate is used in the manufacture of glass; as a precipitating agent in the manufacture of silver emulsions; as an analytical reagent; in making ultramarine and paper pulp; in ceramic glazes and pharmaceuticals; as a food additive; and a filler in synthetic detergents.

Veterinary Drugs and Treatments

Sodium sulfate is used as a saline cathartic, primarily in food animals.

Chemical property

Hygroscopic. Sodium sulfate reacts violently with magnesium. Also incompatible with aluminum, potassium, mercury, lead, calcium, silver, barium, ammonium ions, and strontium. Sulfates give precipitates with salts of lead, barium, strontium, and calcium. Silver and mercury form slightly soluble salts. Alcohol preciptates most sulfates out of solution.

Shipping

UN2630 Selenates or Selenites, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Purification Methods

Crystallise sodium sulfate from water at 30o (1.1mL/g) by cooling to 0o. It becomes anhydrous at 32o.

Incompatibilities

Violent reaction with aluminum, magnesium. Attacks metals in the presence of moisture.

Waste Disposal

Do not discharge waste sodium sulfate directly into sewers or surface waters. Recovered sodium sulfate may be disposed of by burial in a landfill.