Chemical Properties
Ammonium sulfite is a colorless to yellow crystalline (sand-like or sugar-like) solid, normally sold or used in a 40% solution. It is used both as a reducing agent and in photography. This compound is a salt that can form from the reaction of ammonia and sulfur dioxide or hydrogen sulfide. This product is frequently found in the overhead of crude distillation units and can be quite corrosive to steel equipment. Chemical corrosion inhibitors are often used to control corrosion from ammonium sulfite and other ammonium salts.
Physical properties
Colorless monoclinic crystals. Soluble in water, its aqueous solution is alkaline. Slightly soluble in alcohol. Insoluble in acetone and carbon disulfide. It is easily oxidized to ammonium sulfate in air. It can be decomposed into ammonia and sulfur dioxide when heated.
Uses
Ammonium Sulfite is an additive used in the production of
caramel.
Preparation
In the ATS process, sulfur dioxide is absorbed from incinerated Claus tail gas in aqueous ammonia to produce ammonium sulfite and ammonium bisulfite in solution.
Definition
ChEBI: Diammonium sulfite is a p-block molecular entity and a sulfite salt.
General Description
AMMONIUM SULFITE is a colorless crystalline solid. The primary hazard is the threat to the environment. Immediate steps should be taken to limit its spread to the environment. AMMONIUM SULFITE is used in the manufacture of other chemicals, in medicine, and photography.
Air & Water Reactions
Soluble in water.
Reactivity Profile
AMMONIUM SULFITE is a reducing agent. Emits toxic sulfur dioxide and oxides of nitrogen when heated to decomposition [USCG, 1999].
Health Hazard
Inhalation of dust causes irritation of nose and throat. Ingestion causes irritation of mouth and stomach. Dust irritates eyes.
Fire Hazard
Special Hazards of Combustion Products: Toxic sulfur dioxide and oxides of nitrogen may form in fires.
Potential Exposure
Ammonium sulfite is used in medicines,
metal lubricants; explosives, photography, hair wave
solutions; and to make other chemicals. It is also used as a
preservative, and for treating agricultural grain.
Shipping
UN2693 Bisulfites, inorganic, aqueous solutions,
n.o.s., Hazard class: 8; Labels: 8-Corrosive material.
UN3077 Environmentally hazardous substances, solid, n.o.
s., Hazard class: 9; Labels: 9-Miscellaneous hazardous
material, Technical Name Required.
Incompatibilities
A strong reducing agent. Reacts violently
with strong oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep away
from alkaline materials, strong bases, strong acids, oxoacids,
epoxides.
Waste Disposal
Dissolve or mix the material
with a combustible solvent and burn in a chemical incinerator
equipped with an afterburner and scrubber. All federal,state, and local environmental regulations must be
observed. May be buried in a chemical waste landfill in
accordance with federal, state, and local statutes; or, if oxidized
and neutralized, it may be sent to a municipal sewage
treatment plant for biological treatment Incineration.
