Aluminium potassium sulfate dodecahydrate Property

Melting point:

92 °C(lit.)

Boiling point:

200°C

Density 

1.757 g/mL at 25 °C(lit.)

storage temp. 

Store at +5°C to +30°C.

solubility 

H2O: soluble0.5M, clear, colorless

form 

Solid

Specific Gravity

1.757

color 

White

Odor

Odorless

PH Range

3.3

PH

3.0-3.5 (25℃, 50mg/mL in H2O)

Water Solubility 

140 G/L (20 ºC)

Merck 

14,360

Stability:

Stable. Incompatible with steel, aluminium, copper, zinc, bases, strong oxidizing agents.

LogP

-1.031 (est)

CAS DataBase Reference

7784-24-9(CAS DataBase Reference)

NIST Chemistry Reference

potassium aluminum sulfate dodecahydrate(7784-24-9)

Safety

Hazard Codes 

Xn,Xi

Risk Statements 

36/38-22-36/37/38-21/22

Safety Statements 

22-24/25-37/39-26-36-20-13-2

WGK Germany 

3

RTECS 

WS5690000

TSCA 

Yes

HS Code 

28332990

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

Aluminium potassium sulfate dodecahydrate Chemical Properties,Usage,Production

Chemical Properties

white to colourless crystals

Chemical Properties

Aluminum is the most commonly available element in homes and workplaces. Aluminum is readily available for human ingestion through the use of food additives, antacids, buffered aspirin, astringents, nasal sprays, and antiperspirants; from drinking water; from automobile exhaust and tobacco smoke; and from using aluminum foil, aluminum cookware, cans, ceramics, and fi reworks. Workers who are at risk for toxicity are those in refi neries, foundries and also welders and grinders.

Chemical Properties

The PhEur 6.0 describes potassium alum as a granular powder, or colorless, transparent, crystalline masses. The JP XV describes it as colorless or white crystals or powder. Potassium alum is odorless and has a slightly sweet, strongly astringent taste.

Uses

Buffer; floccculating reagent.

Uses

Aluminium potassium sulfate dodecahydrate is a white crystal that is soluble in water. It is made by roasting alunite in a furnace and then harvesting the product by crystallization. Aluminium potassium sulfate dodecahydrate was used to harden gelatin emulsions by introduction, by bathing the exposed plates prior to development, or by use in the fixing bath. Mixed with citric or other acids, it was also used as a clearing bath to remove developer stains in negatives.

Uses

potassium alum (alum) is a cosmetic astringent.

Production Methods

Potassium alum is manufactured by treating bauxite with sulfuric acid and then potassium sulfate. Alternatively, aluminum sulfate is reacted with potassium sulfate.

Definition

A group of double salts withthe formula A₂SO₄.B₂(SO₄)₃.24H₂O,where A is a monovalent metal and Ba trivalent metal. The original examplecontains potassium and aluminium(called potash alum orsimply alum); its formula is oftenwritten AlK(SO₄)₂.12H₂O (aluminiumpotassium sulphate-12-water). Ammoniumalum is AlNH₄(SO₄)₂.12H₂O,chrome alum is KCr(SO₄)₂.12H₂O, etc.The alums are isomorphous and canbe made by dissolving equivalentamounts of the two salts in waterand recrystallizing.

Definition

ChEBI: A hydrate resulting from the the formal combination of anhydrous potassium aluminium sulfate with 12 mol eq. of water.

General Description

Aluminum potassium sulfate dodecahydrate is an inorganic sulfate salt of aluminum and potassium. Linear growth rates of (100), (111) and (110) faces of its crystals have been investigated.

Health Hazard

Prolonged periods of exposure to aluminum and dust cause symptoms of toxicity that include, but are not limited to, coughing, wheezing, shortness of breath, memory loss, learning diffi culty, loss of coordination, disorientation, mental confusion, colic, heartburn, fl atulence, and headaches. Chronic exposures to alumina dust cause irritation to the eyes,

Pharmaceutical Applications

Potassium alum precipitates proteins and is a powerful astringent. The ability to precipitate proteins is utilized in the manufacture of vaccines, where purified proteins are coprecipitated with and adsorbed onto potassium alum.
Potassium alum is often included in preparations used as mouthwashes or gargles and in dermatological preparations, and it may be used as a topical hemostatic, either as a solid or as a solution. Intravesical instillation of potassium alum, typically as a 1% solution, has been used for hemorrhagic cystitis.

Safety

Potassium alum is often included in preparations used as mouthwashes or gargles and in dermatological preparations.
Large doses of potassium alum act as an irritant and may be corrosive; gum necrosis and gastrointestinal hemorrhage have occurred. Acute encephalopathy has been reported following bladder irrigation with alum solutions in the treatment of bladder hemorrhage. Anecdotal evidence suggests that this practice should be avoided for patients with renal insufficiency.

storage

Store in a cool, dry place in tightly closed containers. Stable under normal temperatures and pressures. When kept for a long time at 60–65°C (or over sulfuric acid) potassium alum dodecahydrate loses water, which is reabsorbed on exposure to air. It becomes anhydrous at about 200°C.

Purification Methods

Crystallise it from weak aqueous H2SO4 (ca 0.5mL/g). Its solubility (%) in H2O is 5.7 (0o), 12.0 (20o) and 136.9 (100o).

Incompatibilities

Potassium alum is incompatible with strong oxidizing agents, aluminum, copper, steel, and zinc. When it is dispensed in powders with phenol, salicylates, or tannic acid, gray or green colors may be developed owing to traces of iron in the alum.

Precautions

Aminocarb decomposes on heating and produces toxic fumes, irritating fumes, and oxides of nitrogen. During handling of aminocarb workers should wear protective clothing, gloves, face shield, breathing protection and avoid open flames.

Regulatory Status

GRAS listed. Included in the FDA Inactive Ingredients Database (vaginal; suppository). Included in medicines licensed in the UK.