Бензидин химические свойства, назначение, производство
Описание
Benzidine is a white, greyish-yellow, or slightly reddish crystalline solid or powder. The
major use for benzidine is in the production of dyes, especially azo dyes in the leather, textile,
and paper industries and as a synthetic precursor in the preparation and manufacture
of dyestuffs. It is also used in the manufacture of rubber, as a reagent, and as a stain in
microscopy. It is slightly soluble and slowly changes from a solid to a gas.
Химические свойства
Benzidine is a white, grayish-yellow, or slightly reddish crystalline solid or powder. The
major use for benzidine is in the production of dyes, especially azo dyes in the leather, textile, and paper industries, as a synthetic precursor in the preparation and manufacture of
dyestuffs. It is also used in the manufacture of dyes and rubber, as a reagent, and as a stain
in microscopy. It is slightly soluble and slowly changes from a solid to a gas.
Физические свойства
Grayish-yellow to pale reddish powder or crystals. Darkens on exposure to air or light. Odorless.
Использование
Benzidine was used extensively in the manu facture of dyes. Because of its cancer-causingeffects in humans, its application in dyes hasbeen curtailed. Other uses of this compoundare in chemical analysis: as a reagent for thedetermination of hydrogen peroxide in milkand in the analysis of nicotine. Its hydrochlo ride is used as a reagent to analyze metalsand sulfate.
Подготовка
1-Nitrobenzene restore 1,2-Diphenylhydrazine?turn with acid rearrangement.
Методы производства
Benzidine production is now exclusively for captive consumption and must be carried out in closed systems under stringent workplace controls. Benzidine is used in the synthesisofdyesanddyeintermediates,asahardenerforrubber, and as a laboratory reagent. The ?rst successful synthetic direct dye was Congo Red, a diazo derivative prepared from benzidinebyBoettigerin1884.Nearlyalldirectdyesareazo products. Congo Red is used in humans intravenously for the medical diagnosis of amyloidosis. The basis for its use is an unexplained af?nity for amyloid, which rapidly removes the dye from the blood. It is used medically for the management of profuse capillary hemorrhage such as the one occurring in septicemias and in the terminal phases of leukemia.
Определение
ChEBI: A member of the class of biphenyls that is 1,1'-biphenyl in which the hydrogen at the para-position of each phenyl group has been replaced by an amino group.
Общее описание
A grayish-yellow to grayish-red, crystalline solid. Toxic by ingestion, inhalation, and skin absorption. Combustion produces toxic oxides of nitrogen. Used to make other chemicals and in chemical and biological analysis.
Реакции воздуха и воды
Darkens on exposure to air and light. Soluble in hot water.
Профиль реактивности
Benzidine forms insoluble salts with sulfuric acid. Can be diazotized, acetylated and alkylated. Is hypergolic with red fuming nitric acid . Neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides.
Опасность
Highly toxic by ingestion, inhalation, and
skin absorption. Confirmed carcinogen.
Угроза здоровью
Exposure to benzidine causes irritation to the eyes. Laboratory animals exposed to benzidine at as low as 0.01% to 0.08% in food showed adverse health effects, such as organ
weight decrease in the liver, kidney, and body weight, and an increase in spleen weight,
swelling of the liver, and blood in the urine. Exposure may cause an increase in urination, blood in the urine, and urinary tract tumors. Benzidine is considered acutely toxic
to humans by ingestion, with an estimated oral lethal dose of between 50 and 500 mg/kg.
The symptoms of acute ingestion exposure include cyanosis, headache, mental confusion,
nausea, and vertigo. Dermal exposure may cause skin rashes and irritation. Prolonged
exposure to benzidine causes bladder injury in humans
Профиль безопасности
Confirmed human
carcinogen producing bladder tumors.
Experimental carcinogenic and tumorigenic
data. Poison by ingestion and intraperitoneal
routes. Human mutation data reported. Can
cause damage to blood, including hemolysis
and bone marrow depression. On ingestion
causes nausea and vomiting, which may be
followed by liver and kidney damage. Any
exposure is considered extremely hazardous.
When heated to decomposition it emits
highly toxic fumes of NOx. See also
AROMATIC AMINES.
Канцерогенность
Benzidine is known to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in humans.
Экологическая судьба
Biological. In activated sludge, <0.1% mineralized to carbon dioxide after 5 d (Freitag et al.,
1985). Kincannon and Lin (1985) reported a half-life of 76 d when benzidine in sludge was
applied to a sandy loam soil.
Soil. Benzidine was added to different soils and incubated in the dark at 23 °C under a carbon
dioxide-free atmosphere. After 1 yr, 8.3 to 11.6% of the added benzidine degraded to carbon
dioxide primarily by microbial metabolism and partially by hydrolysis (Graveel et al., 1986).
Tentatively identified biooxidation compounds using GC/MS include hydroxybenzidine, 3-
hydroxybenzidine, 4-amino-4′-nitrobiphenyl, N,N′-dihydroxybenzidine, 3,3′-dihydroxybenzidine
and 4,4′-dinitrobiphenyl (Baird et al., 1977). Under aerobic conditions, the half-life was estimated
to be 2 to 8 d (Lu et al., 1977).
Chemical/Physical. Benzidine is not subject to hydrolysis (Kollig, 1993). Reacts with HCl
forming a salt (C12H12N2?2HCl) that is very soluble in water (61.7 mg/L at 25 °C) (Bowman et al.,
1976).
хранилище
Benzidine should be kept stored in a cool, well-ventilated area, in closed, sealed containers
and out of sunlight and away from heat.
Перевозки
UN1885 Benzidine, Hazard Class: 6.1; Labels:
6.1—Poisonous materials. PGII.
Методы очистки
Its solution in *benzene is decolorized by percolating through two 2-cm columns of activated alumina, then concentrated until benzidine crystallises on cooling. Recrystallise alternately from EtOH and *benzene to constant absorption spectrum [Carlin et al. J Am Chem Soc 73 1002 1951]. It has also been crystallised from hot water (charcoal) and from diethyl ether. Dry it under vacuum in an Abderhalden pistol. Store it in the dark in a stoppered container. CARCINOGENIC. [Beilstein 13 IV 364.]
Несовместимости
Dust may form explosive mixture with
air. Incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. On
contact with strong reducing agents, such as hydrides may
form flammable gases. Keep away from alkaline materials,
strong bases, strong acids, oxoacids, epoxides. Contact with
red fuming nitric acid may cause fire. Oxidizes in air.
Neutralizes acids in exothermic reactions to form salts plus
water. May be incompatible with isocyanates, halogenated
organics, peroxides, phenols (acidic), epoxides, anhydrides,
and acid halides.
Утилизация отходов
Incineration; oxides of nitrogen
are removed from the effluent gas by scrubber, catalytic
or thermal device. Package spill residues and
sorbent media in 17 hour epoxy-lined drums and move to
an EPA-approved disposal site. Treatment may include
destruction by potassium permanganate oxidation, hightemperature
incineration, or microwave plasma methods.
398 Benzidine
Encapsulation by organic polyester resin or silicate fixation.
These disposal procedures should be confirmed with
responsible environmental engineering and regulatory
officials.
Меры предосторожности
At high temperatures, benzidine breaks down and releases highly poisonous fumes.
During use and handling, workers should wear butyl rubber gloves, goggles, and full
body plastic coveralls and ensure that no skin is exposed.
Бензидин препаратная продукция и сырье
сырьё
препарат
КИСЛОТНЫЙ КРАСНЫЙ 114
3,3'-ДИАМИНОБЕНЗИДИН
КИСЛОТНЫЙ ОРАНЖЕВЫЙ 63
Хлоразол черный E
Конго красный
ACID RED 97 (C.I. 22890)
CI NO 22610
CI Пигмент Красный 62
Кислотно-желтый 44
Прямой черный BH
Acid Yellow 42
Кислотно-красный 111
N,N'-БИСБЕНЗИЛИДЕНБЕНЗИДИН
4,4'-дийодбифенил
3,3'-ДИНИТРОБЕНЗИДИН
4,4'-BIPHENYLDICARBONYL CHLORIDE
2,7-Diaminofluorene
N,N'-[1,1'-Biphenyl-4,4'-diylbis(azo)bis(5-hydroxy-7-sodiosulfonaphthalene-6,2-diyl)]bis(glycine sodium) salt
4-Amino-6-[[4'-[(7-amino-1-hydroxy-3-sulfo-2-naphtyl)azo]-1,1'-biphenyl-4-yl]azo]-5-hydroxy-3-[(4-nitrophenyl)azo]-2,7-naphthalenedisulfonic acid trisodium salt
5-Amino-4-hydroxy-3-[[4'-[(2-hydroxy-1-naphthalenyl)azo]-1,1'-biphenyl-4-yl]azo]naphthalene-2,7-disulfonic acid disodium salt
4-Amino-3-[(2,5-dichlorophenyl)azo]-6-[[4'-[(3-methyl-4-hydroxyphenyl)azo]-1,1'-biphenyl-4-yl]azo]-5-hydroxy-2,7-naphthalenedisulfonic acid disodium salt