Aluminum sulfate

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

ACGIH TLV: TWA 2 mg(Al)/m³

Aluminum sulfate (CAS NO 10043-01-3 ) is a chemical compound with the formula Al₂(SO₄)₃ that's sometimes referred to as sulfuric acid, aluminum salt, or cake alum. This chemical is a white crystalline substance which is readily soluble in water, but insoluble in alcohol. When burned at temperatures above 770 degrees centigrade it decomposes to aluminum oxide and gives off toxic, corrosive fumes. Dissolved in water, it creates acidic solutions which will corrode metals. Except in the presence of intense heat, it is non toxic to humans but it may present hazards to the environment.

Physical properties about Aluminum sulfate are: (1)ACD/LogP: -1.031; (2)ACD/LogD (pH 5.5): -5.53; (3)ACD/LogD (pH 7.4): -5.53; (4)ACD/BCF (pH 5.5): 1.00; (5)ACD/BCF (pH 7.4): 1.00; (6)#H bond acceptors: 4 ; (7)#H bond donors: 2 ; (8)Enthalpy of Vaporization: 62.94 kJ/mol; (9)Boiling Point: 330 °C at 760 mmHg; (10)Vapour Pressure: 3.35E-05 mmHg at 25°C

Preparation of Aluminum sulfate: 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.

Uses of Aluminum sulfate: Aluminum sulfate 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+ + 3Na₂SO₄S
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.

When you are using this chemical, please be cautious about it as the following:
1. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice;
2. Do not empty into drains;
3. Avoid release to the environment. Refer to special instructions safety data sheet;
4. Wear suitable gloves and eye/face protection;
5. Do not empty into drains;

You can still convert the following datas into molecular structure:
(1)InChI=1S/2Al.3H2O4S/c;;3*1-5(2,3)4/h;;3*(H2,1,2,3,4)/q2*+3;;;/p-6 ;
(2)InChIKey=DIZPMCHEQGEION-UHFFFAOYSA-H ;
(3)SmilesS(=O)(=O)([O-])[O-].[Al+3].S(=O)(=O)([O-])[O-].S(=O)(=O)([O-])[O-].[Al+3]

The toxicity data is as follows: