Potassium alum

  • Alum
  • Aluminum potassium sulfate
  • Burnt alum
  • Dialuminum dipotassium sulfate
  • Sulfuric acid, aluminum potassium salt (2:1:1)
Formula
KAl(SO4)2
Structure
Description
Colorless, crystalline, odorless powder.
Uses
In dyeing, printing fabrics, manufacture dyes, lakes, paper, vegetable glue.

Registry Numbers and Inventories.
CAS
10043-67-1
EC (EINECS/ELINCS)
233-141-3
RTECS
WS5650000
RTECS class
Mutagen
Merck
12,373
Beilstein/Gmelin
38649 (G)
EPA OPP
128899
Swiss Giftliste 1
G-1052
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
AlKO8S2
Formula mass
258.21
Melting point, °C
92.5
Density
1.725 g/cm3 (20 C)
Solubility in water
568 g/L (20 C)

Hazards and Protection.
Storage
Keep tightly closed in a cool dry location. Store only with compatible chemicals.
Handling
Avoid contace with skin, eyes and clothing. Laboratory use only. Use in a chemical hood with proper protection.
Protection
Chemical splash goggles in compliance with OSHA regulations are advised; however, OSHA regulations also permit other type safety glasses. Whre chemical resistant gloves. To prevent repeated or prolonged skin contact, wear impervious clothing and boots.
Respirators
NIOSH/MSHA approved respirator for exposures of concern.
Small spills/leaks
Evacuate and ventilate area. Wear appropriate protective equipment. Sweep up and place in appropriate container and hold for disposal. Was contaminated surfaces.
Stability
Stable @ ambient temperature potassium alum dodecahydrate when kept long time @ 60-65 C (or over sulfuric acid) loses 9 h2o which is reabsorbed on exposure to air.
Incompatibilities
Strong oxidizing agents.
Decomposition
Toxic and corrosive fumes.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use agent most appropriate to extinguish fire.

Health.
Exposure limit(s)
OSHA: PEL (8 h TWA): 15 mg/m3.
Poison_Class
5
Exposure effects
Aluminum accumulates in brain tissue and is a neurotoxic agent. Ataxia and seizures have been reported following ingestions and in patients with compromised renal function receiving bladder irrigations. Mental status changes, including obtundation, lethargy and confusion, may occur.
   Ingestion
Ingestions of small amounts of alum may cause dryness and a puckering sensation of mucous membranes in the mouth and throat. Rectal enemas containing 1% ammonium alum caused mild cramping and nausea in the majority of patients.
   Inhalation
Inhalation is irritating and may cause airway congestion. Symptoms are usually transient. Respiratory depression has been reported in patients with severe aluminum encephalopathy.
   Skin
Concentrated solutions may irritate abraded skin.
   Eyes
Can cause irritation.

First aid
 
   Ingestion
Dilution: immediately dilute with 4 to 8 ounces (120 to 240 ml) of milk or water (not to exceed 4 ounces/120 ml in a child). Do not induce vomiting.
   Inhalation
If symptoms develop, move individual away from exposure and into fresh air. If symptoms persist, seek medical attention. If breathing is difficult, administer oxygen. Keep person warm and quiet; seek immediate medical attention.
   Skin
Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.