りん酸 化学特性,用途語,生産方法
外観
無色澄明の液体
定義
本品は、次の化学式で表される無機酸である。
性質
リン酸の融点は42.35℃で、沸点は407℃です。融解すると、無色透明な液体になります。
水、アルコール、エーテルなどに溶解します。液体の無水リン酸は強い酸性媒体で、高い電気伝導性を示します。
溶解性
水及びエタノールに溶けやすい。
解説
[別用語参照]リン酸
森北出版「化学辞典（第2版）
用途
ほう素の吸光分析における試料の前処理剤。
用途
汎用試薬。
用途
尿素窒素測定用。
用途
HPLC用溶離液の調製、pH調整用。
用途
食品添加物(酸味剤)。
用途
リン酸塩及び縮合リン酸塩類の原料、金属表面処理、 メッキ、医薬品(ストレプトマイシン、ペニシリン、ビタミンC)、染色、食品(清涼飲料の酸味剤などの食品添加物)、歯みがき(リン酸カルシウム用) 化粧品原料(清浄用化粧品、頭髪化粧品、基礎化粧品、メークアップ化粧品、芳香化粧品、日焼け?日焼け止め化粧品、爪化粧品、口唇化粧品、口腔化粧品、入浴用化粧品)
構造
リン酸の化学式はH3PO4で表されます。モル質量は98.00g/mol、25℃での密度は1.892です。純粋なリン酸は、斜方晶系の不安定な結晶を形成します。
リン酸イオンは正四面体型構造を取っています。リンと酸素の結合距離 (P–O) は、リン酸アルミニウム結晶中で152pmです。
化粧品の成分用途
pH調整剤、香料
合成
リンを燃焼すると五酸化二リンが生成し、希薄なリン酸水溶液に溶かすと純粋なリン酸が得られます。この熱合成法は、環境に優しい方法です。ただし、鉱山で採掘されたリンに含まれている不純物を除去する必要があります。
35％ほどのをリン鉱石と反応させると、リン酸を得ることが可能です。この湿式合成法では、ろ過によって精製可能です。しかし、フッ化水素酸のような不純物が混ざる場合があり、熱合成法よりも純度が低くなります。
4. リン酸と健康
リンは野菜や肉のような生物由来の食物に含まれている元素です。そして、食品や飲料に酸味を出すための添加物としてリン酸が使用されます。
リン自体は人体に必要なミネラルです。18〜49歳の成人の1日の目安量が、厚生労働省により定められています。摂取基準によると、男性が1,050mg、女性が900mgとされています。男女ともに上限量は3,500mgです。
効能
溶解剤
主な用途／役割
ユリア樹脂系接着剤、メラミン樹脂系接着剤、フェノール樹脂系接着剤の触媒として使用される。
使用上の注意
厳寒時には凝固することがある。
説明
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.
化学的特性
Phosphoric acid is a colorless, odorless, crystalline solid or a thick syrupy liquid. Physical state is strength and temperature dependent.
Concentrated phosphoric acid occurs as a colorless, odorless, syrupy liquid. It has a pleasing acid taste when suitably diluted.
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.
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.
物理的性質
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.
天然物の起源
Phosphoric acid is a natural constituent of many fruits and their juices.
来歴
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.
使用
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.
定義
ChEBI: Phosphoric acid is a phosphorus oxoacid that consists of one oxo and three hydroxy groups joined covalently to a central phosphorus atom. It has a role as a solvent, a human metabolite, an algal metabolite and a fertilizer. It is a conjugate acid of a dihydrogenphosphate and a phosphate ion.
調製方法
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.
製造方法
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
一般的な説明
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.
空気と水の反応
Soluble in water with small release of heat.
反応プロフィール
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].
危険性
Phosphoric acid is water soluble and absorbs oxygen readily, and the specific gravity is 1.89, which is heavier than water. It is toxic by ingestion and inhalation and an irritant to the skin and eyes, with a TLV of 1 mg/m3 of air. The four-digit UN identification number is 1805. The NFPA 704 designation is health 3, flammability 0, and reactivity 0. The primary use of phosphoric acid is in chemical analysis and as a reducing agent.
健康ハザード
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/m
3.The acute oral toxicity in rats is reported tobe low, the LD50 value being 1530 mg/kg(NIOSH 1986).
火災危険
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.
使用用途
リン酸は、工業用途として、各種リン酸塩の原料、の化学研磨剤、金属防錆加工剤、金属洗浄剤、清缶剤・耐火物助剤、塗装下地処理剤、活性汚泥、リン酸肥料、試薬等に幅広く利用されています。
また、食品用途として、各種飲料の酸味料や醸造用のpH調整剤、ジュース・コーラ類その他食品の添加物用リン酸塩類の原料として使用可能です。
そのほか、染色用助剤、石油化学用触媒、医薬品添加物などの原料にも用いられます。
脱水反応
リン酸を熱すると、脱水反応が起きます。加熱で生成する混合物は強リン酸と呼ばれ、高温では金属に対する作用も激しいです。
具体的には、150℃で無水物になり、200℃でリン酸2分子が反応して、ピロリン酸が徐々に生成します。高次の縮合リン酸も生じ、300℃以上ではリン酸ユニット1個あたり水分子が1個脱離すると、メタリン酸が生成します。メタリン酸はポリリン酸とも呼ばれ、リン酸が脱水縮合した化合物です。
リン酸と健康
リンは野菜や肉のような生物由来の食物に含まれている元素です。そして、食品や飲料に酸味を出すための添加物としてリン酸が使用されます。
リン自体は人体に必要なミネラルです。18〜49歳の成人の1日の目安量が、厚生労働省により定められています。摂取基準によると、男性が1,050mg、女性が900mgとされています。男女ともに上限量は3,500mgです。
応用例（製薬）
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.
农业用途
Phosphoric acid (H
3PO
4), 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.
工業用途
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.
安全性プロファイル
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
安全性
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
職業ばく露
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.
発がん性
Phosphoric acid was not mutagenic in
bacterial assays.
貯蔵
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.
輸送方法
UN1805 Phosphoric acid solution, Hazard class: 8; Labels: 8-Corrosive material. UN3543 Phosphoric acid solid, Hazard class: 8; Labels: 8-Corrosive material.
不和合性
Phosphoric acid is a strong acid and reacts with alkaline substances.
Mixtures with nitromethane are explosive.
廃棄物の処理
Add slowly to solution of soda ash and slaked lime with stirring, then flush to sewer with large volumes of water.
規制状況(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.
りん酸 上流と下流の製品情報
原材料
準備製品