発煙硫酸

外観

無色～わずかにうすい褐色, 油状の液体, 又は白色～わずかにうすい褐色, 結晶

溶解性

水に分解。硫酸と任意の割合で混和する。

解説

濃硫酸に多量の三酸化硫黄(いおう)SO3を吸収させたもの。SO3の含有量の低いものは粘性のある油状の液体で、オレウムoleumともよばれる。つねに三酸化硫黄の蒸気を発して白煙を出すのでこの名がある。接触式硫酸製造法において、三酸化硫黄の溶解量（遊離SO3という）が30％以下のものがつくられる（これを水で希釈して濃硫酸としている）。SO3濃度が高くなると固体となる。おもな成分は二硫酸H2S2O7のようなポリ硫酸である。SO3 25％の比重1.9262（15℃）。融点－11℃（SO3 20％）、－0.6℃（SO3 25％）、15.2℃（SO3 30％）。水に触れると強く発熱する。ほとんどの金属を侵す。皮膚に触れると重症のやけどを生じるので取扱い注意。クロロ硫酸の原料として染料、火薬、薬品の原料に用いられる。

用途

有機及び無機合成原料(スルホン化剤)、油脂及び鉱油の精製、濃硫酸の再生。

用途

発煙硫酸中のSO3の求電子性を利用した強力なスルホン化剤，脱水剤であり，各種スルホン酸，ニトロ化合物製造用，不飽和炭化水素の吸収剤に用いられる．

用途

有機及び無機化合物合成原料(スルホン化剤）、油脂及び鉱油の精製、濃硫酸の再生。

用途

有機及び無機合成原料。

製法

大気中の水分と三酸化硫黄蒸気から生じる硫酸霧の白煙を発生するのでこの名がある．

使用上の注意

発煙性及び刺激性が強い。

説明

Fuming sulfuric acid is also called oleum, which is a trade name. It is a heavy, oily liquid, colorless to dark brown depending on purity, and fumes strongly in moist air and is extremely hygroscopic. Fuming sulfuric acid is a solution of sulfur trioxide in sulfuric acid. Sulfur trioxide is forced into solution with sulfuric acid to the point that the solution cannot hold any more. As soon as the solution is exposed to air, the fuming begins, forming dense vapor clouds. It is violently water reactive, as are most acids. Oleum is also a strong irritant to tissue. The four-digit UN identification number is 1831.

化学的特性

viscous liquid, is a mixture of sulfur trioxide dissolved in sulfuric acid. The SO3 content may range between 15 and 30%.

物理的性質

Dithionic acid, H2S2O6, is a chemical compound known only in solution. This acid is dibasic and salts called dithionates are known. All dithionates are readily soluble in water. They are mild oxidizing and mild reducing agents.

使用

In manufacture of fertilizers, explosives, dyestuffs, other acids, parchment paper, glue, purification of petroleum, pickling of metal.

一般的な説明

Thick fuming yellow liquid. Density 16.5 lb / gal. Very toxic by inhalation. Corrosive to metals and tissue, quickly causing severe burns. Used to make chemicals, dyes, explosives and in petroleum refining.

空気と水の反応

Fumes in air. Soluble in water; dissolution generates dangerous amounts of heat that can cause localized boiling and spattering of the acidic mixture and generate heavy fumes. During sulfonation of mononitrobenzene with fuming sulfuric acid, a leak from an internal cooling coil permitted water to enter the reaction tank. A violent eruption occurred due to the heat of solution [MCA Case History 944(1963)].

反応プロフィール

SULFURIC ACID reacts as a strong acid, as an oxidizing agent and as a dehydrating agent. Chars wood, sugar and many other organic materials on contact. The heat from these reactions may ignite the wood, sugar or organic matter. May react explosively with acetic acid, acetic anhydride, acetonitrile, acrolein, acrylic acid, acrylonitrile, allyl alcohol, allyl chloride, ammonium hydroxide, aniline, cresol, butyraldehyde, cumene, ethyl acetate, ethylene diamine, ethylene glycol, glyoxal, isoprene, isopropyl alcohol, methyl ethyl ketone, propylene oxide, pyridine, styrene, vinyl acetate; strong bases (sodium hydroxide, potassium hydroxide) or mineral acids (nitric acid, hydrochloric acid, hydrofluoric acid) [Lewis, 3rd ed., 1993, p. 1195]. Mixing in equal molar portions with any of the following substances in a closed container caused the temperature and pressure to increase: 2-aminoethanol, ammonium hydroxide (28%), chlorosulfonic acid, ethylenediamine, ethyleneimine, ethylene cyanohydrin, hydrochloric acid (36%), hydrofluoric acid (48.7%), isopropyl alcohol, nitric acid (70%), 2-nitropropane, propiolactone, propylene oxide, pyridine, styrene monomer, sodium hydroxide, sulfolane, vinyl acetate, vinylidene chloride [NFPA 1991]. Extremely hazardous in contact with carbides, bromates, chlorates, fulminates, picrates, and powdered metals. May induce violent polymerization in polymerizable organic compounds such as allyl chloride. Reacts exothermically with sodium hypochlorite to produce chlorine gas.

危険性

Reacts violently with water. Strong irritant to tissue.

健康ハザード

Acid mist is irritating to eyes, nose and throat. Liquid causes severe burns of skin and eyes.

火災危険

Special Hazards of Combustion Products: Toxic and irritating vapors are generated.

安全性プロファイル

Confirmed human carcinogen. A poison. Moderately toxic by inhalation. A corrosive irritant to skin, eyes, and mucous membranes. A very dangerous fire hazard by chemical reaction with reducing agents and carbohydrates. A severe explosion hazard by chemical reaction with acetic acid, acetic anhydride, acetonitrile, acrolein, acrylic acid, acrylonitrile, allylalcohol, allyl chloride, 2-amino ethanol, NH4OH, aniline, cresol, n-butyraldehyde, cumene, dichloroethyl ether, diethylene glycol monomethyl ether, diisobutylene, epichlorohydrin, ethyl acetate, ethylene cyanohydrin, ethylene diamine, ethylene glycol, ethylene glycol monoethyl ether acetate, ethylene imine, glyoxal, HCl, HF, isoprene, isopropyl alcohol, mesityl oxide, methyl ethyl ketone, HNO3, 2-nitropropane7 p-propiolacetone, propylene oxide, pyridine, NaOH, styrene monomer, vinylidene chloride, sulfolane, vinyl acetate. Will react with water or steam to produce heat and toxic and corrosive fumes. Can react vigorously with reducing materials. When heated to decomposition it emits highly toxic fumes of SOx. See also SULFUROUS ACID.

職業ばく露

Used as a chemical feedstock in the manufacture of acetic acid, hydrochloric acid; citric acid; phosphoric acid; aluminum sulfate; ammonium sulfate;barium sulfate; copper sulfate; phenol, superphosphates, titanium dioxide; as well as synthetic fertilizers, nitrate explosives; artificial fibers; dyes, pharmaceuticals, detergents, glue, paint, and paper. It finds use as a dehydrating agent for esters and ethers due to its high affinity for water; as an electrolyte in storage batteries; for the hydrolysis of cellulose to obtain glucose; in the refining of mineral and vegetable oil; and in the leather industry. Other uses include fur and food processing; carbonization of wool fabrics; gas drying; uranium extraction from pitchblende; and laboratory analysis. Sulfuric acid is among the highestvolume produced chemical in the United States.

輸送方法

UN1830 Sulfuric acid with ＞51% acid or sulfuric acid with not ＞51% acid, Hazard class: 8; Labels: 8-Corrosive material. UN1831 Sulfuric acid, fuming with 30% or more free sulfur trioxide and Sulfuric acid, fuming, with ＜30% free sulfur trioxide, Hazard class: 8; Labels: 8-Corrosive material. UN1832 Sulfuric acid, spent, Hazard class: 8; Labels: 8-Corrosive material.

不和合性

A strong acid and oxidizer. Reacts violently with water with dangerous spattering and evolution of heat. Reacts violently with combustible and reducing materials; bases, organic materials; chlorates, carbides, picrates, fulminates, water, powdered metals. Corrosive to most common metals forming explosive hydrogen gas.

廃棄物の処理

Add slowly to solution of soda ash and slaked lime with stirring; flush to drain with large volumes of water. Recovery and reuse of spent sulfuric acid may be a viable alternative to disposal, and processes are available.