Aluminum sulfate

Molecular Structure of Aluminium sulfate (CAS NO.10043-01-3):

IUPAC Name: dialuminum trisulfate
Aluminum sulfate 's Molecular formula: Al₂O₁₂S₃
Aluminum sulfate 's Molar mass: 342.15
EINECS: 233-135-0
Melting point: 770 °C
H bond acceptors: 4
H bond donors: 2
Freely Rotating Bonds: 0
Polar Surface Area: 82.98Ų
Enthalpy of Vaporization: 62.94 kJ/mol
Boiling Point: 330 °C at 760 mmHg
Density: 2.71 g/mL at 25 °C(lit.)
Vapour Pressure: 3.35E-05 mmHg at 25°C
InChI
InChI=1/2Al.3H2O4S/c;;3*1-5(2,3)4/h;;3*(H2,1,2,3,4)/q2*+3;;;/p-6
Smiles
S(=O)(=O)([O-])[O-].[Al+3].S(=O)(=O)([O-])[O-].S(=O)(=O)([O-])[O-].[Al+3]
Product Categories: Industrial/Fine Chemicals; Inorganics; Aluminum Salts; Metal and Ceramic Science; Salts
Other names: Cake alum ; Filter alum ; Papermaker's alum ; Alunogenite ; Sulfuric acid,aluminum salt (3:2)

 Aluminum sulfate(Alum) has two prime uses. It is bought by the pulp and paper industry for coagulating and coating pulp fibers into a hard paper surface by reacting with small amounts of sodium carboxylates (soap) present. Aluminum salts of carboxylic acids are very gelatinous. In water purification it serves as a coagulant, pH conditioner, and phosphate and bacteria remover. It reacts with alkali to give an aluminum hydroxide floc that drags down such impurities in the water. For this reason it also helps the taste of water.
     6RCO₂^-Na⁺ + Al₂(SO₄)₃ → 2(RCO₂^-)₃Al³⁺ + 3Na₂SO₄
       Al₂(SO₄)₃ + 6NaOH → 2Al(OH)₃ + 3Na₂SO₄

  Pharmaceutically, aluminum sulfate is employed in dilute solution as a mild astringent and antiseptic for the skin. The most important single application of aluminum sulfate is in clarifying water; sodium aluminate, which is basic, is sometimes used with aluminum sulfate, which is acid, to produce the aluminum hydroxide.

  Aluminum sulfate is also used in sizing of paper, as a mordant in the dye industry, chemical manufacturing, concrete modification, soaps, greases, fire extinguishing solutions, tanning, cellulosic insulation, and in some baking powders.

 Aluminum sulfate [Al₂(SO₄)₃] is manufactured from aluminum oxide (Al₂O₃, alumina, bauxite). A mixture of the crude ore and sulfuric acid is heated at 105 to 110 ℃ for 15 to 20 hours.
           Al₂O₃.2H₂O + 3H₂SO₄ → Al₂(SO₄)₃ + 5H₂O
 Filtration of the aqueous solution is followed by evaporation of the water to give the product, which is processed into a white powder.

Reported in EPA TSCA Inventory. EPA FIFRA 1988 pesticide subject to registration or re-registration.

Moderately toxic by ingestion and intraperitoneal routes. Experimental reproductive effects. Human mutation data reported. Hydrolyzes to form sulfuric acid, which irritates tissue, especially lungs. When heated to decomposition it emits toxic fumes of SO_x.
Hazard Codes: Xi, N
The Risk Statements information of  Aluminum sulfate:
37/38:  Irritating to respiratory system and skin 
41:  Risk of serious damage to eyes 
51/53:  Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment 
36/37/38:  Irritating to eyes, respiratory system and skin
The Safety Statements information of  Aluminum sulfate:
26:  In case of contact with eyes, rinse immediately with plenty of water and seek medical advice 
39:  Wear eye/face protection 
61:  Avoid release to the environment. Refer to special instructions safety data sheet 
37/39:  Wear suitable gloves and eye/face protection 
29:  Do not empty into drains
RIDADR: UN 1760/3077
WGK Germany: 1

ACGIH TLV: TWA 2 mg(Al)/m³