ChemicalBook >  Product Catalog >  Inorganic chemistry >  Inorganic acid >  Phosphoric acid

Phosphoric acid

Basic information Uses Safety Related Supplier

Phosphoric acid Basic information

Product Name:
Phosphoric acid
CAS:
7664-38-2
MF:
H3O4P
MW:
98
EINECS:
231-633-2
Mol File:
7664-38-2.mol
More
Less

Phosphoric acid Chemical Properties

Melting point:
~40 °C(lit.)
Boiling point:
158 °C(lit.)
Density 
1.685 g/mL at 25 °C(lit.)
vapor density 
3.4 (vs air)
vapor pressure 
2.2 mm Hg ( 20 °C)
FEMA 
2900 | PHOSPHORIC ACID
refractive index 
n20/D 1.433
storage temp. 
Store below +30°C.
solubility 
H2O: soluble
form 
Solid or Viscous Liquid
pka
2.1-7.2-12.3(at 25℃)
color 
≤10(APHA)
Specific Gravity
1.7
PH
<0.5 (100g/l, H2O, 20℃)
Water Solubility 
MISCIBLE
λmax
λ: 260 nm Amax: ≤0.05
λ: 280 nm Amax: ≤0.04
Merck 
14,7344
BRN 
1921286
Exposure limits
TLV-TWA 1 mg/m3 (ACGIH, MSHA, and OSHA); TLV-STEL 3 mg/m3 (ACGIH).
InChIKey
NBIIXXVUZAFLBC-UHFFFAOYSA-N
CAS DataBase Reference
7664-38-2(CAS DataBase Reference)
NIST Chemistry Reference
Phosphoric acid(7664-38-2)
EPA Substance Registry System
Phosphoric acid (7664-38-2)
More
Less

Safety Information

Hazard Codes 
C,Xn,T,F
Risk Statements 
34-35-22-39/23/24/25-36/38-23/24/25-11
Safety Statements 
7-16-26-36/37-45-36/37/39-1/2-24/25
RIDADR 
UN 3453 8/PG 3
WGK Germany 
3
RTECS 
TB6300000
3-10
TSCA 
Yes
HS Code 
2809 20 00
HazardClass 
8
PackingGroup 
III
Hazardous Substances Data
7664-38-2(Hazardous Substances Data)
Toxicity
ADI 0 to 70 mg / kg (total phosphate content in terms of phosphorus, FAO / WHO, 2001).
GRAS (FDA, § 182.1073, 2000).
LD501530mg / kg (rat, oral).
In case of daily intake of 2 ~ 4 g, it can cause mild diarrhea. The amount of sour agent used as a cola drink is 0.02% to 0.06%.

MSDS

More
Less

Phosphoric acid Usage And Synthesis

Uses

It has many uses, including the manufacture of soaps and detergents, sugar refining, water treatment, animal feeds, electroplating, gasoline additive, and binder for foods, to name a few.

Description

Phosphoric acid was prepared first by Robert Boyle in 1694 by dissolving phosphorus pentoxide in water. Phosphoric acid is probably the most important compound of phosphorus. It is the second largest inorganic chemical by volume, after sulfuric acid, marketed in the United States.
The single most important application of Phosphoric acid is manufacturing phosphate salts for fertilizers. Such fertilizer phosphates include sodium, calcium, ammonium, and potassium phosphates. Other applications are in metal pickling and surface treatment for removal of metal oxides from metal surfaces; electropolishing of aluminum; as a bonding agent in various refractory products such as alumina and magnesia; as a catalyst in making nylon and gasoline; as a dehydrating agent; in fireproofing wood and fabrics; in lithographic engraving; in textile dyeing; in dental cement; in coagulating rubber latex; in purifying hydrogen peroxide; and as a laboratory reagent. Dilute solutions of phosphoric acid are used as additives to carbonated beverages for a pleasing sour taste. Also, dilute acid is used in refining sugar; as a nutrient; and as a buffering agent in preparing jam, jelly, and antibiotics. The commercial phosphoric acid is 85% (w/w) in strength.

Chemical Properties

Phosphoric acid is a colourless, odourless chemical substance.
Phosphoric acid on combustion forms toxic fumes (phosphorous oxides) and decomposes on contact with alcohols, aldehydes, cyanides, ketones, phenols, esters, sulphides, and halogenated organics producing toxic fumes. It violently polymerises under the influence of azo compounds and epoxides attacks many metals forming flammable/explosive gas. Phosphoric acid violently polymerises under the influence of azo compounds and epoxides, reacting violently with bases. It has wide-scale application in industries, in the manufacture of superphosphates for fertilisers, phosphate salts, polyphosphates, and detergents, as a catalyst in ethylene manufacture and hydrogen peroxide purification as a flavour, acidulant, synergistic anti-oxidant, and sequestrant in food. In dental cements, in process engraving, metal rustproofing, latex coagulation, analytical reagent, and as a veterinary product in the treatment of lead poisoning. Food-grade phosphoric acid is used to acidify foods and beverages. It provides a tangy or sour taste and, being a mass-produced chemical, is available cheaply and in large quantities. Phosphoric acid, used in many soft drinks, has been linked to lower bone density in epidemiological studies. In brief, phosphoric acid is a strong acid and common industrial chemical used in the manufacture of a wide number of products, notably porcelain and metal cleaners, detergents, and fertilisers. It is also used as a food additive and is a major constituent of many soft drinks. Low phosphate concentrations are found in drinking water to which it is added in some areas in order to reduce lead solubility.

Chemical Properties

Phosphoric acid is a colorless, odorless, crystalline solid or a thick syrupy liquid. Physical state is strength and temperature dependent.

Chemical Properties

Concentrated phosphoric acid occurs as a colorless, odorless, syrupy liquid.

Chemical Properties

Phosphoric acid is odorless. It has a pleasing acid taste when suitably diluted. For a detailed description of this compound, refer to Burdock (1997).

Physical properties

Pure phosphoric acid, also called orthophosphoric acid, is a clear, colorless, mineral acid with moderate strength. It is normally marketed as an aqueous solution of 75–85% in which it exists as a clear, viscous liquid.

Physical properties

Chemists refer to orthophosphoric acid as phosphoric acid, which is the IUPAC name for this compound. The prefix “ortho” is used to distinguish the acid from other phosphoric acids, which are generally called polyphosphoric acids. Orthophosphoric acid is a nontoxic, rather weak triprotic acid. When pure, it is a solid at STP. Orthophosphoric acid is a very polar molecule which makes it highly soluble in water. The valence state of phosphorous in orthophosphoric acid and other phosphoric acids is +5. Triprotic means that the orthophosphoric acid molecule can dissociate up to three times, producing a hydrogen cation, H+, each time.

Occurrence

Phosphoric acid is a natural constituent of many fruits and their juices.

History

Phosphoric acid was produced but not identified by alchemists in ancient times. It derives its name from the element phosphorus, which was discovered in 1669 by Henning Brand (1630 1710).Scheele subsequently isolated phosphorus from bone ash and produced phosphoric acid by reacting phosphorus and nitric acid. Scheele's method replaced bone as the main source of phosphorus rather than urine.
John Bennett Lawes (1814 1900) patented a process in 1841 of making superphosphate from bones and later extended his process to phosphates obtained from rock. Superphosphates are made by treating Ca3(PO4)2 with sulfuric acid to make more soluble calcium hydrogen phosphates: Ca3(PO4)2 + 2H2SO4 Ca(H2PO4)2 + 2CaSO4. In this reaction Ca(H2PO4)2 is monobasic calcium phosphate, which is also called superphosphate. Calcium hydrogen phosphates (superphosphates) are more water soluble and therefore more readily available to plants.

Uses

Phosphoric acid is second only to sulfuric acid as an industrial acid and consistently ranksin the top 10 chemicals used globally.States, but it is used in a number of other applications. Phosphateswere used as builders and water softeners. A builder is a substance added to soaps or detergentsto increase their cleansing power.
Phosphoric acid is used as an intermediate in the production of animal feed supplements,water treatment chemicals, metal surface treatments, etching agent, and personal care productssuch as toothpaste. It is used as a catalyst in the petroleum and polymer industry. Phosphoricacid is used in food as a preservative, an acidulant, and flavor enhancer; it acidifies carbonateddrinks such as Coca Cola and Pepsi, giving them a tangy flavor. Phosphoric acid is used as arust remover and metal cleaner. Naval Jelly is approximately 25% phosphoric acid. Other usesfor phosphoric acid include opacity control in glass production, textile dyeing, rubber latexcoagulation, and dental cements.

Uses

Phosphoric acid (H3PO4) is the most important oxoacid of phosphorus and its main use is in the manufacture of fertilisers .
Within the human body, phosphate is the main phosphorus-containing compound. Phosphate is an inorganic compound and is the salt of phosphoric acid. It can form organic esters with a variety of compounds and these are important in many biochemical processes. Phosphate has the empirical formula PO43-. It is a tetrahedral molecule, where the central phosphorus atom is surrounded by four oxygen atoms.
In biological systems, phosphate is often found either as the free ion (inorganic phosphate) or as an ester after reaction with organic compounds (often referred to as organic phosphates). Inorganic phosphate (mostly denoted as Pi) is a mixture of HPO42- and H2PO4- at physiological pH.

Uses

Phosphoric anhydride is a solid, which is very strongly moisture absorbing and is mainly used as a desiccant.

Uses

Phosphoric acid is one of the most widelyused chemicals. Among its most importantapplications are its use in fertilizers anddetergents, in pickling and rustproofing metals, as a catalyst, and as an analytical reagent.

Uses

phosphoric acid is a preservative and an anti-oxidant. It is irritating to the skin in concentrated solutions.

Uses

In the manufacture of superphosphates for fertilizers, other phosphate salts, polyphosphates, detergents. Acid catalyst in making ethylene, purifying hydrogen peroxide. As acidulant and flavor, synergistic antioxidant and sequestrant in food. Pharmaceutic aid (solvent). In dental cements; process engraving; rustproofing of metals before painting; coagulating rubber latex; as analytical reagent.

Uses

Phosphoric Acid is an acidulant that is an inorganic acid produced by burning phosphorus in an excess of air, producing phosphorus pentoxide which is dissolved in water to form orthophosphoric acid of varying concentrations. it is a strong acid which is soluble in water. the acid salts are termed phosphates. it is used as a flavoring acid in cola and root beer beverages to provide desirable acidity and sourness. it is used as a synergistic antioxidant in vegetable shorten- ings. in yeast manufacture, it is used to maintain the acidic ph and provide a source for phosphorus. it also functions as an acidulant in cheese. it is also termed orthophosphoric acid.

Uses

Phosphorous acid is used for reaction with inorganic and organic products, for water treatment, industrial and agricultural uses. It is also used to bleach industrial and cleaning supplies. Contact

Definition

ChEBI: A phosphorus oxoacid that consits of one oxo and three hydroxy groups joined covalently to a central phosphorus atom.

Preparation

Low-purity technical grade phosphoric acid for use in fertilizers is produced from phosphate rocks by digestion with concentrated sulfuric acid. The apatite types, primarily consisting of calcium phosphate phosphate rocks, are used: Ca3(PO4)2 + 3H2SO4 + 6H2O → 2H3PO4 + 3(CaSO4•2H2O)
The insoluble calcium sulfate slurry is filtered out. Acid from this wet process is impure but can be purified by various methods. Purification steps involve precipitation, solvent extraction, crystallization, and ion exchange techniques.
Phosphoric acid also can be made by many different methods. Dissolution of phosphorus pentoxide in water and boiling yields phosphoric acid. Pure phosphoric acid can be obtained by burning phosphorus in a mixture of air and steam:
P4 (l) + 5O2 (g) →P4O10 (s)
P4O10 (s) + H2O (g) → 4H3PO4 (l)
The acid also may be prepared by heating violet phosphorus with 33% nitric acid:
4P + 10HNO3 + H2O → 4H3PO4 + 5NO ↑ + 5NO2 ↑
or by heating red phosphorus with nitric acid (1:1). The overall equation is:
P + 3HNO3 → H3PO4 + NO + 2NO2

Production Methods

The majority of phosphoric acid is made by digesting phosphate rock (essentially tricalcium phosphate) with sulfuric acid; the phosphoric acid is then separated by slurry filtration. Purification is achieved via chemical precipitation, solvent extraction, crystallization, or ion exchange.

brand name

Pharmaceutic aid (solvent).

General Description

A clear colorless liquid or transparent crystalline solid. The pure solid melts at 42.35°C and has a density of 1.834 g / cm3. Liquid is usually an 85% aqueous solution. Shipped as both a solid and liquid. Corrosive to metals and tissue. Used in making fertilizers and detergents and in food processing.

Air & Water Reactions

Soluble in water with small release of heat.

Reactivity Profile

Phosphorous acid reacts exothermically with bases. May react with active metals, including such structural metals as aluminum and iron, to release hydrogen, a flammable gas. Can initiate the polymerization of certain classes of organic compounds. Reacts with cyanide compounds to release gaseous hydrogen cyanide. May generate flammable and/or toxic gases in contact with dithiocarbamates, isocyanates, mercaptans, nitrides, nitriles, sulfides, and strong reducing agents. Forms explosive mixture with nitromethane. Reacts violently with sodium tetrahydroborate. In the presence of chlorides can corrode stainless steel to form explosive hydrogen gas. Emits toxic and irritating fumes of oxides of phosphorus when heated to decomposition [Lewis, 3rd ed., 1993, p. 1029].

Health Hazard

Burns on mouth and lips, sour acrid taste, severe gastrointestinal irritation, nausea, vomiting, bloody diarrhea, difficult swallowing, severe abdominal pains, thirst, acidemia, difficult breathing, convulsions, collapse, shock, death.

Health Hazard

Phosphoric acid is less corrosive and hazardous than is concentrated sulfuric or nitricacid. Its concentrated solutions are irritantsto the skin and mucous membranes. Thevapors (P2O5 fumes) can cause irritation tothe throat and coughing but could be tolerated at <10 mg/m3.The acute oral toxicity in rats is reported tobe low, the LD50 value being 1530 mg/kg(NIOSH 1986).

Fire Hazard

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.

Pharmaceutical Applications

Phosphoric acid is widely used as an acidifying agent in a variety of pharmaceutical formulations. It is used in pharmaceutical products as part of a buffer system when combined with a phosphate salt such as sodium phosphate, monobasic or dibasic. It is also widely used in food preparations as an acidulant, flavor, and synergistic antioxidant (0.001–0.005%) and sequestrant.
Therapeutically, dilute phosphoric acid has been used welldiluted in preparations used in the treatment of nausea and vomiting. Phosphoric acid 35% gel has also been used to etch tooth enamel and to enhance delivery of drugs through the nail.
) Nanosized hydroxyapatite powder was made by combining phosphoric acid with egg shells.

Agricultural Uses

Orthophosphoric acid is obtained by reacting phosphorus pentoxide with water or by reacting rock phosphate with concentrated sulphuric acid. Salts of ammonium,calcium or potassium with this acid are called orthophosphates, and these are used as fertilizers. Nearly 80% of the phosphorus pentoxide in fertilizers is derived from orthophosphoric acid. Commercial phosphates based on orthophosphoric acid, also known as phosphoric acid, are triple superphosphate, ammonium phosphate, ammonium polyphosphate, nitrophosphate, orthophosphate fertilizer and liquid fertilizers.

Agricultural Uses

Phosphoric acid (H3PO4), also known as orthophosphoric acid, is the most significant source of phosphate fertilizers. Phosphoric acid based fertilizers mainly include ammonium phosphate, diammonium phosphate and monoammonium phosphate.
Phosphoric acid is deliquescent and commercially the most important derivative of phosphorus, accounting for over 90% of the phosphate rock mined. The white rhombic solid is highly soluble in water and ethanol, and the concentrated aqueous solution is generally available for use.
Phosphoric acid is used in several industries other than the fertilizer industry. Most elemental phosphorus is converted into phosphoric acid for non-fertilizer use. There are two basic processes for the production of phosphoric acid.
Metaphosphoric acid is obtained by heating phosphoric acid until dense white fumes begin to appear. The product is highly deliquescent and glassy in appearance. Its salts are known as metaphosphates. Orthophosphoric acid is the most common and is used as an important phosphate ingredient in commercial fertilizers.

Industrial uses

As a cleanser for metals, phosphoric acid produces a light etch on steel, aluminum, or zinc, which aids paint adhesion. Deoxidine is a phosphoric acid cleanser for metals. Nielite D is phosphoric acid with a rust inhibitor, used as a nonfuming pickling acid for steel. Albrite is available in 75, 80, and 85% concentrations in food and electronic grades, both high-purity specifications. DAB and Phosbrite are called Bright Dip grades, for cleaning applications. Phosphoric anhydride, or phosphorus pentoxide, P2O5, is a white, water-soluble powder used as a dehydrating agent and also as an opalizer for glass. It is also used as a catalyst in asphalt coatings to prevent softening at elevated temperatures and brittleness at low temperatures.

Safety Profile

Human poison by ingestion. Moderately toxic by skin contact. A corrosive irritant to eyes, skin, and mucous membranes, and a systemic irritant by inhalation. A common air contaminant. A strong acid. Mixtures with nitromethane are explosive. Reacts with chlorides + stainless steel to form explosive hydrogen gas. Potentially violent reaction with solum tetrahydroborate. Dangerous; when heated to decomposition it emits toxic fumes of POx

Safety

In the concentrated form, phosphoric acid is an extremely corrosive and harmful acid. However, when used in pharmaceutical formulations it is usually very diluted and is generally regarded as an essentially nontoxic and nonirritant material.
The lowest lethal oral dose of concentrated phosphoric acid in humans is reported to be 1286 mL/kg.
(rabbit, skin): 2.74 g/kg
(rat, oral): 1.53 g/kg

Chemical Synthesis

The elemental phosphorus is burned to produce phosphorous pentoxide (P2O5), which is then hydrated. The heat is then removed and the phosphoric acid (H3PO4) is collected as a fine mist. Another important source of phosphoric acid is from phosphate rocks by treatment with sulfuric acid; this is the so-called wet-acid process. The synthesis of pure phosphoric acid involves several steps including a time-consuming, expensive step, the sublimation of white phosphorus.

Potential Exposure

Phosphoric acid is used in the manufacture of fertilizers, phosphate salts; polyphosphates, detergents, activated carbon; animal feed; ceramics, dental cement; pharmaceuticals, soft drinks; gelatin, rust inhibitors; wax, and rubber latex. Exposure may also occur during electropolishing, engraving, photoengraving, lithographing, metal cleaning; sugar refining; and water-treating.

storage

When stored at a low temperature, phosphoric acid may solidify, forming a mass of colorless crystals, comprising the hemihydrate, which melts at 28°C. Phosphoric acid should be stored in an airtight container in a cool, dry place. Stainless steel containers may be used.

Shipping

UN1805 Phosphoric acid solution, Hazard class: 8; Labels: 8-Corrosive material. UN3543 Phosphoric acid solid, Hazard class: 8; Labels: 8-Corrosive material.

Incompatibilities

The substance is a medium strong acid. Incompatible with strong caustics; most metals. Readily attacks and reacts with metals forming flammable hydrogen gas. Do not mix with solutions containing bleach or ammonia. Violently polymerizes on contact with azo compounds; epoxides, and other polymerizable compounds. Decomposes on contact with metals, alcohols, aldehydes, cyanides, ketones, phenols, esters, sulfides, halogenated organics; producing toxic fumes. Corrosive to common metals and possibly to some rubbers and plastics.

Incompatibilities

Phosphoric acid is a strong acid and reacts with alkaline substances. Mixtures with nitromethane are explosive.

Waste Disposal

Add slowly to solution of soda ash and slaked lime with stirring, then flush to sewer with large volumes of water.

Regulatory Status

GRAS listed. Accepted as a food additive in Europe. Included in the FDA Inactive Ingredients Database (infusions, injections, oral solutions, topical creams, lotions, ointments and solutions, and vaginal preparations). Included in nonparenteral and parenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.

More
Less

Phosphoric acidSupplierMore

- Gold
Tel:
0536-3292139
Email:
sd262500@163.com
Shanghai Aladdin Bio-Chem Technology Co.,LTD Gold
Tel:
021-20337333/400-620-6333
Email:
sale@aladdin-e.com
Shanghai neon biological technology co., LTD Gold
Tel:
021-54252912-8903
Email:
leona.xin@forneeds.cn
Jiangsu Bohan Industry and Trade Co., Ltd. Gold
Tel:
13605157325
Email:
lzw_199901@hotmail.com
VWR(Shanghai) Co., Ltd Gold
Tel:
400-821-8006
Email:
Info_China@vwr.com
Basic information Uses Safety Related Supplier