Нитробензол химические свойства, назначение, производство
Описание
Nitrobenzene is a greenish-yellow crystal or yellow oily liquid, and is slightly soluble in water. The primary hazard of nitrobenzene is toxicity; however, it is also combustible. The boiling point is about 410°F, the flash point is 190°F, and the ignition temperature is 900°F. The specific gravity is 1.2, which is heavier than water, and the material will sink to the bottom. The vapor density is 4.3, which is heavier than air. Nitrobenzene is toxic by ingestion, inhalation, and skin absorption, with a TLV of 1 ppm in air. The four-digit UN identification number is 1652. The NFPA 704 designation is health 3, flammability 2, and reactivity 1. Nitrobenzene is a nitro hydrocarbon derivative, but it is not very explosive. The primary uses are as a solvent, an ingredient of metal polishes and shoe polishes, and in the manufacture of aniline.
Химические свойства
Nitrobenzene is a pale yellow to dark brown
oily liquid whose odor resembles bitter almonds (or black
paste shoe polish).
Физические свойства
Clear, light yellow to brown, oily liquid with an almond-like or shoe polish odor. May darken on
exposure to air. An experimentally determined odor threshold concentration of 4.7 ppbv was
reported by Leonardos et al. (1969). A detection odor threshold concentration of 9.6 mg/m3 (1.9
ppmv) was determined by Katz and Talbert (1930).
Использование
Nitrobenzene is an organic compound used a standard for detection and analyses as well as its removal from the environment. The compound’s cytotoxic effects have been studied in a hepatocarcinoma cell line.
Определение
nitrobenzene: A yellow oily liquid,C6H5NO2; r.d. 1.2; m.p. 6°C; b.p.211°C. It is made by the nitration ofbenzene using a mixture of nitricand sulphuric acids.
Методы производства
Nitrobenzene is produced by the direct nitration of benzene with a mixture of
sulfuric and nitric acids. U.S. capacity for nitrobenzene production is approximately
1.5 billion pounds . The most important use for
nitrobenzene is in the production of aniline. Nearly 98% of the nitrobenzene
produced in the U.S. is converted to aniline.
Подготовка
Nitrobenzene is produced commercially by the exothermic nitration of benzene with fuming nitric acid in the presence of a sulfuric acid catalyst at 50 to 65℃. The crude nitrobenzene is passed through washer-separators to remove residual acid and is then distilled to remove benzene and water.
Реакции воздуха и воды
Very slightly soluble in water.
Профиль реактивности
Aluminum chloride added to Nitrobenzene containing about 5% phenol caused a violent explosion [Chem. Eng. News 31:4915. 1953]. Heating a mixture of Nitrobenzene, flake sodium hydroxide and a little water led to an explosion, discussed in [Bretherick's 5th ed. 1995]. Mixed with oxidants, i.e. dinitrogen tetraoxide, fluorodinitromethane, nitric acid, peroxodisulfuric acid, sodium chlorate, tetranitromethane, uranium perchlorate, etc., forms highly sensitive explosive, [Bretherick 5th ed, 1995]. Heated mixtures of Nitrobenzene and tin(IV) chloride produce exothermic decomposition with gas production [Bretherick, 5th Ed., 1995].
Опасность
Toxic by ingestion, inhalation, and skin
absorption. Methemoglobinemia. Possible carcinogen.
Угроза здоровью
The routes of entry of nitrobenzene intothe body are the inhalation of its vaporsor absorption of the liquid or the vaporthrough the skin and, to a much lesserextent, ingestion. The target organs are theblood, liver, kidneys, and cardiovascular system. Piotrowski (1967) estimated that in anexposure period of 6 hours to a concentration of 5 mg/m3, 18 mg of nitrobenzene wasabsorbed through the lungs and 7 mg throughthe skin in humans. Furthermore, about 80%of inhaled vapor is retained in the respiratorytract. The dermal absorption rate at this concentration level is reported as 1 mg/h, whilethe subcutaneous absorption of the liquidis between 0.2 and 0.3 mg/cm3/h (ACGIH1986).
The symptoms of acute toxicity are headache, dizziness, nausea, vomiting, and dyspnea. Subacute and chronic exposure cancause anemia. Nitrobenzene effects the conversion of hemoglobin to methemoglobin. Itis metabolized to aminophenols and nitrophenols to about 30%, which are excreted.
Пожароопасность
Moderate explosion hazard when exposed to heat or flame. Reacts violently with nitric acid, aluminum trichloride plus phenol, aniline plus glycerine, silver perchlorate and nitrogen tetroxide. Avoid aluminum trichloride; aniline; gycerol; sulfuric acid; oxidants; phosphorus pentachloride; potassium; potassium hydroxide. Avoid sunlight, physical damage to container, freezing, and intense heat.
Промышленное использование
Nitrobenzene is mainly utilized for aniline production. The aniline is used primarily
for the manufacture of 4,4'-methylenebis (phenyl isocyanate) and polymers
thereof (50%). The second largest use of aniline is in the manufacture of chemicals
for rubber production (30%). Dyes and dye intermediates, hydroquinone and drugs
account for about 8% of the aniline produced, while 10% of the aniline is
converted to agricultural products such as pesticides and defoliants (Northcott
1978). It also is used as a solvent for cellulose ethers and an ingredient in polishes
for metals and shoes (HSDB 1988).
Профиль безопасности
Confirmed carcinogen.
Human poison by an unspecified route.
Poison experimentally by subcutaneous and
intravenous routes. Moderately toxic by
ingestion, skin contact, and intraperitoneal
routes. Human systemic effects by ingestion:
general anesthetic, respiratory stimulation,
and vascular changes. An experimental
teratogen. Experimental reproductive
effects. Mutation data reported. An eye and
skin irritant. Can cause cyanosis due to
formation of methemoglobin. It is absorbed
rapidly through the skin. The vapors are
hazardous.
to heat and flame. Moderate explosion
hazard when exposed to heat or flame.
Explosive reaction with solid or
concentrated alkali + heat (e.g., sodium
hydroxide or potassium hydroxide),
aluminum chloride + phenol (at 12O°C),
aniline + glycerol + sulfuric acid, nitric +
sulfuric acid + heat. Forms explosive
mixtures with aluminum chloride, oxidants
(e.g., fluorodinitromethane, uranium
perchlorate, tetranitromethane, sodium
chlorate, nitric acid, nitric acid + water,
peroxodsulfuric acid, dinitrogen
tetraoxide), phosphorus pentachloride,
potassium, sulfuric acid. Reacts violently
with aniline + glycerin, N20, AgCLO4. To
fight fne, use water, foam, CO2, dry
chemical. Incompatible with potassium
hydroxide. When heated to decomposition it
emits toxic fumes of NOx. See also NITRO
COMPOUNDS OF AROMATIC
HYDROCARBONS.
Возможный контакт
Nitrobenzene is used in the manufacture
of explosives and aniline dyes and as solvent and intermediate.
It is also used in floor polishes; leather dressings
and polished; and paint solvents, and to mask other
unpleasant odors. Substitution reactions with nitrobenzene
are used to form m-derivatives. Pregnant women may be
especially at risk with respect to nitrobenzene as with many
other chemical compounds, due to transplacental passage
of the agent. Individuals with glucose-6-phosphate dehydrogenase
deficiency may also be special risk groups.
Additionally, because alcohol ingestion or chronic alcoholism
can lower the lethal or toxic dose of nitrobenzene,
individuals consuming alcoholic beverages may be at risk.
Канцерогенность
Nitrobenzene is reasonably anticipated to be a human carcinogenbased on sufficient evidence of carcinogenicity from studies in experimental animals.
Перевозки
UN1662 Nitrobenzene, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials.
Методы очистки
Common impurities include nitrotoluene, dinitrothiophene, dinitrobenzene and aniline. Most impurities can be removed by steam distillation in the presence of dilute H2SO4, followed by drying with CaCl2, and shaking with, then distilling at low pressure from BaO, P2O5, AlCl3 or activated alumina. It can also be purified by fractional crystallisation from absolute EtOH (by refrigeration). Another purification process includes extraction with aqueous 2M NaOH, then water, dilute HCl, and water, followed by drying (CaCl2, MgSO4 or CaSO4) and fractional distillation under reduced pressure. The pure material is stored in a brown bottle, in contact with silica gel or CaH2. It is very hygroscopic. [Beilstein 5 H 233, 5 I 124, 5 II 171, 5 III 591, 5 IV 708.]
Несовместимости
Concentrated nitric acid, nitrogen tetroxide;
caustics; phosphorus pentachloride; chemically-active
metals, such as tin or zinc. Violent reaction with strong oxidizers
and reducing agents. Attacks many plastics. Forms
thermally unstable compounds with many organic and inorganic
compounds.
Утилизация отходов
Incineration (982℃, 2.0 seconds
minimum) with scrubbing for nitrogen oxides abatement
. Consult with environmental regulatory agencies
for guidance on acceptable disposal practices. Generators
of waste containing this contaminant (≥100 kg/mo) must
conform with EPA regulations governing storage, transportation,
treatment, and waste disposal.
Нитробензол препаратная продукция и сырье
сырьё
препарат
МЕТИЛ 6-ХИНОЛИНАЦЕТАТ
4-(2-THIENYL)BUTYRIC ACID
3-аминобензол-1-сульфонамид
6,10,12-trichloronaphth[2,3-c]acridine-5,8,14(13H)-trione
polythiniren
8-хлорхинолин
4-аминофенил эфир
1,5-НАФТИРИДИН-2-КАРБОКСИЛИНАЦИД
Vat Green 1
3-Hydroxy-4-methoxybenzaldehyde
1-Chlorophthalazine
Плумбагин
6-Метокси-2-нафтойной кислоты
Натрий 3-нитробензолсульфона
4 - (4-метоксифенил) масл ной кислоты
Димидиум бромид
4-нитроса
Quintozine
8-амино-6-метоксихинолин
METANILIC ACID SODIUM SALT
SOLVENT BLACK 5
3-METHYL-1H-PYRAZOLO[3,4-C]PYRIDAZINE-4,5-DIOL
Метаnilic кислота
Анилин
6-Бром-3-оксихинолин
2-бензотиазолол
Disperse Blue 148
(6-METHYL-BENZOFURAN-3-YL)-ACETIC ACID
4'-Hydroxyvalerophenone
2-Ацетил-6-метоксинафталин
3',5'-диметокси-4'-гидроксиацетофенон
N, N'-бис (3-метилфенил) -N, N'-бис (фенил) бензидин
3-Нитроанилин
Disperse Red 60
1,3-дихлорбензол
3-Аминофенол
АМИНОДИФЕНИЛАМИН-4
НиGRозин
FUCHSIN BASIC
1,3-ДИНИТРОБЕНЗОЛ