1314-56-3 Usage
Description
Phosphorus pentoxide, also known as phosphoric anhydride, is a white amorphous powder or colorless monoclinic crystal at room temperature. It is generated by the combustion of white, yellow, or red phosphorus in dry air. This highly deliquescent solid has a melting point of 580-585°C and a sublimation point of 347°C. It is insoluble in acetone and ammonia but soluble in sulfuric acid. Phosphorus pentoxide is corrosive to metals and tissue and is moderately toxic.
Uses
Used in Chemical Industry:
Phosphorus pentoxide is used as a drying and dehydrating agent, a condensation reagent in organic synthesis, and a laboratory reagent. It is also used for the preparation of high purity phosphoric acid, phosphates, and phosphate-based aerosols.
Used in Semiconductor Industry:
Phosphorus pentoxide is used as a semiconductor silicon doped source, a dehydration drying agent, an organic synthetic condensing agent, and a surfactant. It is also used for the preparation of high purity phosphoric acid.
Used in Glass Manufacturing:
Phosphorus pentoxide is used in the manufacture of optical glass, UV transparent glass, insulating glass, microcrystalline glass, and opaque glass. It improves the dispersion coefficient and UV light transmission ability of the glass.
Used in Pharmaceutical and Pesticide Production:
Phosphorus pentoxide is used as a raw material for the production of pharmaceuticals and pesticides.
Used in Agricultural Applications:
Phosphorus pentoxide, known as phosphoric anhydride, has a great affinity for water and dissolves in it to give phosphoric acid. It is used in fertilizers, with the weight percentage of phosphorus specified as phosphorus pentoxide.
Used in Organic Synthesis:
Phosphorus pentoxide is used as a dehydrating agent, in organic synthesis, and in hydrocarbon analysis.
Used in Fire Extinguishing:
Phosphorus pentoxide is used in fire extinguishing, and when it reacts with water, it emits heat and white smoke.
Used in Optical Fiber Preform Manufacturing:
High purity grade phosphorus pentoxide can be used as a dopant for drawing optical fiber preforms and as an N-type dopant for the manufacture of integrated circuits.
Used in Optical Crystal Synthesis:
Phosphorus pentoxide is used for the synthesis of optical crystals.
Hazardous characteristics
Non-combustible. But encountering water and organic materials such as wood, cotton or straw, it reacts violently to release heat, may cause a fire. Contacting Water, it can emit a lot of smoke and heat. The case of the moisture, it corrodes most metals slightly. A strong local irritation, vapor with dust can severely irritate the eyes, mucous membranes, skin and respiratory system, and corrode the skin, mucous membranes. Even the dust concentration of 1mg/m3, it is unbearable.
The above information is edited by the lookchem of Yan Yanyong.
Reference quality standards
Item Index
Chemically pure analytically pure specific level
Content (phosphorus pentoxide) ≥99% ≥99.5% ≥99.5%
Active R value 1.2 1.7 2.0
Reducing substances (in terms P2O3) ≤0.02% ≤0.01% ≤0.005%
Clarity test Pass Pass Pass
Water insoluble matter ≤0.02% ≤0.01% ≤0.01%
Total nitrogen (N) ≤0.002% ≤0.001% ≤0.001%
Heavy Metals (in Pb) ≤0.002% ≤0.001% ≤0.001%
Iron content (Fe) ≤0.002% ≤0.001% ≤0.001%
Arsenic content (As) ≤0.01% ≤0.005% ≤0.0025%
Reaction with water
It reacts with cold water to produce extremely toxic metaphosphate: P2O5 + H2O = 2HPO3
and reacts with hot water to produce ontoxic orthophosphate: P2O5 + 3H2O = (heating) 2H3PO4, an exothermic reaction, the phenomenon is not very intense.
Toxicity
Phosphorus pentoxide smoke irritates mucous membranes, has irritation and burning effects for skin (tissue dehydration).
Maximum allowable concentration is 1mg/rn3.
Production equipment and pipelines should be closed, and maintain good ventilation. Production workers should wear labor protective equipments and wear protective respirator, when there are phosphorus pentoxide vapor and smoke , should wear protective masks. Pay attention to protect the skin, do not import, or meet the eye. If accidentally touches the skin, immediately wash with clean water.
Water absorption
There is a strong water imbibition, and easily deliquescent in the air, corrosive to the skin. The maximum allowable concentration in the workplace is 1mg/m3. The drying efficiency of Phosphorus pentoxide is 1 cubic meter 0.00001 grams of water vapor content at 298K, namely dried by phosphorus pentoxide, water left per cubic meter of air is up to 0.00001 gram, phosphorus pentoxide can make sulfuric acid, nitric acid dehydration. When the amount of phosphorus pentoxide and water substance is 1: 6, phosphorus pentoxide can convert to orthophosphoric acid.
Production method
Reagent grade phosphorus pentoxide is as raw material, purified by burning sublimation in sufficiently dry oxygen gas stream, trapping sublimate by the condenser, to obtain high-purity phosphorus pentoxide products.
Yellow phosphorus is heated and melted by oxidation method, transfered to the oxidation furnace for oxidation combustion reaction with dry air (via dehydration of concentrated sulfuric acid), phosphorus pentoxide produced is sublimated by heat, cold in the top of burners and falls into interior settling chamber at the bottom, to prepare pentoxide products.
Exhaust escapes from the oxidation furnace to a cyclone to recover phosphorus pentoxide dust. Recycling and the settling chamber finished product are together packaged as a finished product.
P4 + 5O2 → 2P2O5
Production Methods
Phosphorus pentoxide or phosphoric anhydride (P2O5) is
formed by burning yellow phosphorus in dry air or oxygen.
Preparation
Phosphorus pentoxide is prepared by burning phosphorus in a plentiful supply of dry air or oxygen: P4 + 5O2 → P4O10 The crude product may contain a small amount of sesquioxide, P2O3, which may be removed by sublimation in ozonized oxygen.
Air & Water Reactions
Readily absorbs moisture from the air forming a syrup of meta-, pyro-, and orthophosphoric acids. Reacts violently with water releasing considerable heat [Oldbury Chemicals, p. 9].
Reactivity Profile
Phosphorus pentoxide reacts violently and exothermically with water. The heat can ignite surrounding or admixed combustible materials. Undergoes hazardous or violent reactions with metal hydroxides and oxides, formic acid, hydrogen fluoride and hydrofluoric acid, iodides, metals (in particular potassium and sodium), oxidizing agents (bromine pentafluoride, chlorine trifluoride, perchloric acid, oxygen difluoride, hydrogen peroxide), ammonia, and proparygl alcohol. [Bretherick, 5th ed., 1995, p. 1781; EPA, 1998]. A violent explosion occurs if a solution of perchloric acid in chloroform is poured over phosphorus pentaoxide [EPA, 1998].
Hazard
Phosphorus pentoxide is a strong irritant. It is corrosive to skin and contact with eyes can be injurious.
Health Hazard
Because of its dehydrating action, phosphorus pentoxide is a highly corrosive substance. It is an irritant to the eyes, skin, and mucous membranes.Inhalation of its vapors caused chronic pulmonary edema, injury to lungs, and hemorrhage in test animals. The LC50 values varied significantly with the species.LC50 value, inhalation (rats): 127 mg/m3/h .
Fire Hazard
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.
Safety Profile
Poison by inhalation. A
corrosive irritant to the eyes, shin, and
mucous membranes. With the appropriate
conditions it undergoes hazardous reactions
with formic acid, hydrogen fluoride,
inorganic bases, iodides, metals, methyl
hydroperoxide, oxidants (e.g., bromine,
pentafluoride, chlorine trifluoride, perchloric
acid, oxygen Difluoride, hydrogen peroxide),
3-propynol, water. When heated to
decomposition it emits toxic fumes of POx.
Potential Exposure
This material is used as an intermediate in organic synthesis, catalyst, condensing agent; dehydrating agent; in the preparation of acrylate esters, surfactants, sugar refining; medicine, fire extinguishing; and special glasses.
Purification Methods
It has been sublimed at 250o under vacuum into glass ampoules. It fumes in moist air and reacts violently with water. It is an excellent drying agent for use in desiccators. HARMFUL VAPOURS and attacks skin. [Manley J Chem Soc 121 331 1922, Klements in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 541 1963.]
Incompatibilities
Reacts violently and exothermically with water, forming ignition level heat and highly corrosive phosphoric acid. Keep away from the combination of moisture and combustible materials. Phosphorus pentoxide reacts violently with the following: perchloric acid; ammonia, hydrofluoric acid; oxidizers, hydrogen fluoride; formic acid, oxygen difluoride, potassium, sodium, propargyl alcohol; calcium oxide; inorganic bases; sodium hydroxide and chlorine trifluoride. Attacks many metals in presence of water. Incompatible with 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, alcohols, ammonia. Undergoes hazardous or violent reactions with metal hydroxides and oxides, formic acid, hydrogen fluoride and hydrofluoric acid, iodides, metals (in particular potassium and sodium), ammonia, and proparygl alcohol.
Waste Disposal
Decompose with water, forming phosphoric and hydrochloric acids. The acids may then be neutralized and diluted slowly to solution of soda ash and slaked lime with stirring then flush to sewer with large volumes of water.
Check Digit Verification of cas no
The CAS Registry Mumber 1314-56-3 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 1,3,1 and 4 respectively; the second part has 2 digits, 5 and 6 respectively.
Calculate Digit Verification of CAS Registry Number 1314-56:
(6*1)+(5*3)+(4*1)+(3*4)+(2*5)+(1*6)=53
53 % 10 = 3
So 1314-56-3 is a valid CAS Registry Number.
InChI:InChI=1/O5P2/c1-6(2)5-7(3)4
