ACID SULPHATES

Ammonium hydrogen sulphate (NH₄HSO₄). Colourless crystals.
Syn: Ammonium bisulphate, ammonium acid sulphate.
Potassium hydrogen sulphate (KHSO₄). Colourless crystals.
Syn: Potassium bisulphate.
Potassium pyrosulphate (K₂S₂O₇). White powder.
Sodium hydrogen sulphate (NaHSO₄.H₂O). White crystalline solid.
Syn: Sodium bisulphate.
Sodium pyrosulphate (Na₂S₂O₇). White crystalline powder. Contains sodium hydrogen sulphate.
INCOMPATIBILITY
Acid sulphates are incompatible with alkalis, hypochlorites and any material which reacts with sulphuric acid, such as oxidising material, organic material and other acids. Heating produces toxic fumes of sulphur.
HEALTH HAZARD DATA
All of the above compounds are highly acidic as solids and as strong solutions. They will cause severe burns to skin and eyes. They also cause severe internal irritation and permanent damage if inhaled or ingested.
HANDLING and GENERAL PRECAUTIONS
Avoid skin and eye contact.
Avoid inhalation or ingestion of the powder.
Keep away from heat.
Keep away from alkalis.
Keep away from hypochlorites.
Keep the container tightly sealed.
Wash hands thoroughly after handling.
Wearing protective clothing to avoid any sort of contact. A long sleeved laboratory coat or gown, rubber gloves and a face mask as a minimum standard. If there is any chance of a splash occurring wear a full face shield.
TREATMENTS
Skin ­ remove contaminated clothing and immediately wash the affected area with large amounts of water until all evidence of the chemical has been removed (approximately 15 minutes). If irritation persists or burns develop seek immediate medical attention. Wash contaminated clothing before re­use.
Eyes ­ immediately wash the affected eye with large amounts of water until all evidence of the chemical has been removed (approximately 15 minutes). If irritation persists or blurred vision develops seek immediate medical attention.
Inhalation ­ remove from the area of exposure to fresh air. If breathing has ceased apply artificial respiration. Keep warm and allow to rest. If irritation or pain persist seek immediate medical attention.
Ingestion ­ wash out the mouth thoroughly with water and give water to drink followed by milk of magnesia. Seek immediate medical attention. Milk of magnesia should be part of your laboratory first aid kit if acid sulphates are handled in your laboratory. Milk of magnesia is available off the shelf in pharmacies.
STORAGE
Store in a tightly sealed container in a cool dry atmosphere away from heat.
DISPOSAL
Wear rubber gloves, safety glasses and laboratory coat.
Spills: Solid - collect in a beaker, dissolve in a large amount of water. Add soda ash, mix and neutralise with 6M hydrochloric acid and discharge to sewer with large excess of water.
Solution - cover with soda ash, mix and scoop into a beaker of water. Neutralise with 6M hydrochloric acid and discharge to sewer with a large excess of water. If a spill contains a fluoride, add slaked lime in addition to the above treatment.
Package lots: Add slowly to a large container of water. Stir in a slight excess of soda ash. If fluoride is present add slaked lime. Let stand for 24 hours. Decant or siphon into another container and neutralise with 6M hydrochloric acid. Discharge to sewer with a large excess of water. The sludge may be added to land fill.
ENVIRONMENT:
Acid sulphates form sulphuric acid when exposed to moisture and as such will harm animal, plant and water life. Corrosion of sewers can occur so must never be disposed of to sewer.

BACK to the top of the Glossary Contents List
BACK to the top of the Chemical Contents List

REFERENCES