Phosphoric anhydride

  • Phosphoric pentoxide
  • Phosphorous pentoxide
  • Diphosphorus pentaoxide
Formula
P2O5
Structure
Description
White crystalline powder, slight phosphorus-like odor, deliquescent.
Uses
Prepn of phosphorus oxychloride & metaphosphoric acid, acrylate esters, surfactants, sugar refining, laboratory reagent, fire extinguishing, special glasses.

Registry Numbers and Inventories.
CAS
1314-56-3
EC (EINECS/ELINCS)
215-236-1
EC Index Number
015-010-00-0
EC Class
Corrosive
S 22 26 45
RTECS
TH3945000
RTECS class
Other
UN (DOT)
1807
Merck
12,7512
Beilstein/Gmelin
20550 (G)
Swiss Giftliste 1
G-3676
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
O5P2
Formula mass
141.96
Melting point, °C
562
Vapor pressure, mmHg
1
Density
2.253 g/cm3 (20 C)
Solubility in water
Decomposes
Heat of vaporization
94.9 kJ/mol

Hazards and Protection.
Storage
Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from water. Keep away from metals. Corrosives area. Keep containers tightly closed. Keep away from strong bases.
D1A E
Handling
Wash thoroughly after handling. Wash hands before eating. Do not allow water to get into the container because of violent reaction. Do not get in eyes, on skin, or on clothing. Keep container tightly closed. Do not ingest or inhale. Do not store near combustible materials.
Protection
Eyes: Wear chemical goggles and a face shield if splashing is possible. Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear butyl rubber gloves, apron, and/or clothing. Wear appropriate gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Do not flush into a sewer. Wash area with soap and water. Clean up spills immediately, using the appropriate protective equipment. Sweep up or absorb material, then place into a suitable clean, dry, closed container for disposal. Provide ventilation. Do not get water on spilled substances or inside containers.
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Incompatible with sodium, aluminum, potassium, ammonia, peroxides, and magnesium. Upon contact with water, diphosphorus pentoxide reacts violently producing heat and an acidic solution. Diphosphorus pentoxide reacts violently with barium sulfide, hydrogen fluoride, and iodides. Forms an explosive mixture with methyl hydroperoxide. Contact with 3-propynol causes ignition to occur.
Decomposition
Oxides of phosphorus, phosphorous fumes.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Will react with water to form toxic and corrosive fumes. Extinguishing media: Do NOT use water directly on fire. Use dry chemical, carbon dioxide, or alcohol-resistant foam. Do NOT get water inside containers. Cool containers with flooding quantities of water until well after fire is out.
Fire potential
Nonflammable. Does not support combustion. With the appropriate conditions it undergoes hazardous reactions with formic acid; Inorganic bases; iodides; methyl hydroperoxide. Reacts violently with water to evolve heat, dangerous fire risk
Hazards
Reacts violently with water to evolve heat. Flammable poisonous gases may accumulate in tanks and hopper cars. Phosphorus pentoxide reacts violently with the following: ammonia, hydrofluoric acid, oxygen difluoride, potassium, sodium, propargyl alcohol, calcium oxide, sodium hydroxide and chlorine trifluoride. A violent explosion occurs if a solution of perchloric acid in chloroform is poured over phosphorus pentoxide. Avoid formic acid, hydrogen fluoride, inorganic bases, metals, oxidants, water. Readily absorbs moisture from air to form meta-, pryo-, or orthophosphoric acid.
Combustion products
Fire will produce irritating, corrosive and/or toxic gases. Reaction with water may generate much heat which will increase the concentration of fumes in the air.
Health
3
 
Flammability
0
 
 
Reactivity
2
 

Health.
Exposure limit(s)
MAK: 1 ppm; mg/m3; (1996).
Poison_Class
2
Exposure effects
Early symptoms of chronic phosphorous intoxication include gastrointestinal distress and possibly a garlic-like odor to the breath. Chronic exposure can lead to necrosis of the jaw, or 'phossy-jaw'.
   Ingestion
Causes gastrointestinal tract burns. Causes severe pain, nausea, vomiting, diarrhea, and shock.
   Inhalation
May cause severe irritation of the respiratory tract with sore throat, coughing, shortness of breath and delayed lung edema. Causes chemical burns to the respiratory tract. May cause pulmonary edema and severe respiratory disturbances.
   Skin
Causes severe skin irritation and burns.
   Eyes
Causes eye burns. May cause irreversible eye injury.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If breathing is difficult, give oxygen. Get medical aid. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   Skin
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse. Destroy contaminated shoes.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Extensive irrigation is required (at least 30 minutes).

Transport.
UN number
1807
Response guide
Hazard class
8
Packing Group
II
 
HS Code
2809 10 00
 
Std. Transport #
4932324