Hydrazin Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
FARBLOSE, RAUCHENDE UND HYGROSKOPISCHE FLüSSIGKEIT MIT STECHENDEM GERUCH.
CHEMISCHE GEFAHREN
Zersetzung unter Bildung von Ammoniakrauchen, Wasserstoff und Stickstoffoxiden. Feuer- und Explosionsgefahr. Starkes Reduktionsmittel. Reagiert sehr heftig mit Oxidationsmitteln. Mittelstarke Base. Reagiert sehr heftig mit vielen Metallen, Metalloxiden und por?sen Materialien unter Feuer- und Explosionsgefahr. Luft oder Sauerstoff sind für die Zersetzung nicht erforderlich.
ARBEITSPLATZGRENZWERTE
TLV: 0.01 ppm (als TWA); Hautresorption; Krebskategorie A3 (best?tigte krebserzeugende Wirkung beim Tier mit unbekannter Bedeutung für den Menschen); (ACGIH 2005).
MAK: Hautresorption; Sensibilisierung der Haut; Krebserzeugend Kategorie 2; (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den K?rper durch Inhalation der D?mpfe, über die Haut und durch Verschlucken.
INHALATIONSGEFAHREN
Beim Verdampfen bei 20°C kann sehr schnell eine gesundheitssch?dliche Kontamination der Luft eintreten.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Die Substanz ver?tzt die Augen und die Haut. Der Dampf dieser Substanz ver?tzt die Atemwege. Inhalation des Dampfes kann zu Lungen?dem führen (s. Anm.). M?glich sind Auswirkungen auf Leber, Nieren und Zentralnervensystem. Exposition kann zum Tod führen. Die Auswirkungen treten u.U. verz?gert ein. ?rztliche Beobachtung notwendig.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
Wiederholter oder andauernder Kontakt kann zu Hautsensibilisierung führen. M?glich sind Auswirkungen auf Leber, Nieren und Zentralnervensystem. M?glicherweise krebserzeugend für den Menschen.
LECKAGE
Gefahrenbereich verlassen! Fachmann zu Rate ziehen! Ausgelaufene Flüssigkeit in abdichtbaren Beh?ltern sammeln. Reste mit Sand oder inertem Absorptionsmittel aufnehmen und an einen sicheren Ort bringen. NICHT mit S?gemehl oder anderen brennbaren Absorptionsmitteln binden. NICHT in die Umwelt gelangen lassen. Pers?nliche Schutzausrüstung: Vollschutzanzug mit umgebungsluftunabh?ngigem Atemschutzger?t.
R-S?tze Betriebsanweisung:
R45:Kann Krebs erzeugen.
R23/24/25:Giftig beim Einatmen, Verschlucken und Berührung mit der Haut.
R34:Verursacht Ver?tzungen.
R43:Sensibilisierung durch Hautkontakt m?glich.
R50/53:Sehr giftig für Wasserorganismen, kann in Gew?ssern l?ngerfristig sch?dliche Wirkungen haben.
R10:Entzündlich.
R51/53:Giftig für Wasserorganismen, kann in Gew?ssern l?ngerfristig sch?dliche Wirkungen haben.
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
R20/21/22:Gesundheitssch?dlich beim Einatmen,Verschlucken und Berührung mit der Haut.
R19:Kann explosionsf?hige Peroxide bilden.
R11:Leichtentzündlich.
S-S?tze Betriebsanweisung:
S53:Exposition vermeiden - vor Gebrauch besondere Anweisungen einholen.
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn m?glich, dieses Etikett vorzeigen).
S61:Freisetzung in die Umwelt vermeiden. Besondere Anweisungen einholen/Sicherheitsdatenblatt zu Rate ziehen.
S60:Dieses Produkt und sein Beh?lter sind als gef?hrlicher Abfall zu entsorgen.
S36/37/39:Bei der Arbeit geeignete Schutzkleidung,Schutzhandschuhe und Schutzbrille/Gesichtsschutz tragen.
Beschreibung
Hydrazine sulphate, hydrobromide and hydrochloride
have been reported to be occupational sensitizers,
mainly in soldering flux.
Chemische Eigenschaften
HYDRAZINE, colorless, fuming liquid, decomposes when heated above 350 °C at atmospheric pressure into N2 and NH2, also decomposes in presence of a catalyst (e.g., platinum) into N2 and NH3. Hydrazine burns when ignited in air with a violet-colored flame. The compound is soluble in all proportions with H2O and is soluble in alcohol. Hydrazine forms a hydrate with one molecule of H2O. Upon moderate heating or in a vacuum, the hydrate yields hydrazine and H2O. Hydrazine is a base slightly weaker than NH4OH.
Physikalische Eigenschaften
Colorless, mobile, fuming liquid; ammoniacal odor; density 1.0045 g/mL at25°C; refractive index 1.46044 at 22°C; solidifies at 2°C to a white crystallinesolid; boils at 113.5°C; flash point 52°C; burns with a violet flame; vapor pres-sure 14.4 torr at 25°C; critical temperature 379.85°C; critical pressure 145atm; surface tension 66.67 dyne/cm at 25°C; dielectric constant 51.7 at 25°C;viscosity 0.876 centipoise at 25°C; very soluble in water; forms an azeotropewith water at molar composition of 58.5% hydrazine: 41.5% water (71.48%:28.52% by weight), the azeotrope with water boils at 120.5°C; forms hydrazinehydrate at 1:1 molar concentration in water; soluble in alcohols and other polar solvents; pKa 8.1 at 25°C.
Verwenden
Hydrazine is used as a high-energy rocket fuel, as a
reducing agent, and for preparing organic hydrazine derivatives.
The propellant grade of commercial hydrazine is more
than 97.7% active. It is also used as an oxygen scavenger in
boiler water. Hydrazine has also been used as an experimental
drug for treating tuberculosis and sickle cell anemia.
Definition
A colorless
liquid that can be prepared by the oxidation
of ammonia with sodium
chlorate(I) or by the gas phase reaction of
ammonia with chlorine. Hydrazine is a
weak base, forming salts (e.g. N
2H
4.HCl)
with strong acids. It is a powerful reducing
agent, reducing salts of the noble metals to
the metal. Anhydrous hydrazine ignites
spontaneously in oxygen and reacts violently
with oxidizing agents. The aqueous
solution, hydrazine hydrate, has been used
as a fuel for jet engines and for rockets.
Vorbereitung Methode
Hydrazine is a colorless, fuming, oily liquid with an
ammonia-like odor. It should be stored in glass containers
in a cool, dark place.
Hydrazine is prepared commercially by the Raschig and
the urea processes. The Raschig method involves reacting
sodium hypochlorite with excess ammonia, flash boiling to
recover dilute hydrazine, and fractionating to produce the
hydrate. In the urea process, urea is oxidized with hypochlorite
to produce the hydrate. Both anhydrous hydrazine and the
hydrate are fuming, strongly basic (pKb1=5.52), colorless
liquids. Hydrazine may ignite under various circumstances
(e.g., on contact with rust) and it decomposes violently in
contact with oxidizing materials. It is usually stored under
nitrogen to reduce the flammability hazard and to maintain
purity.
Allgemeine Beschreibung
Colorless liquid with an ammonia-like odor. A violent poison. Causes delayed eye irritation. Very corrosive, attacks glass, rubber, and cork. Corrodes molybdenum steels such as Allegheny stainless 316.
It is a strong reducing agent and a flammable liquid and vapour. Hydrazine is a useful building block in organic synthesis of pharmaceuticals and pesticides. There are many kinds of hydrazine compounds, including hydrazine, 1,1-dimethylhydrazine, and 1,2-dimethylhydrazine. Small amounts of hydrazine occur naturally in plants. Most hydrazines are manufactured for use as rocket propellants and fuels, boiler water treatments, chemical reactants, medicines, and in cancer research. Hydrazines are highly reactive and easily catch fire.
Air & Water Reaktionen
Fumes in air. Water soluble.
Reaktivit?t anzeigen
HYDRAZINE are strongly basic and are powerful reducing agents. Note that a 64% solution corresponds to the composition hydrazine hydrate (N2H4.H2O). Spontaneous ignition can occur with hydrogen peroxide and nitric acid. Contact with metallic oxide surfaces may lead to flaming decomposition [Haz. Chem. Data (1966)]. The reaction between 2,4-dinitrochlorobenzene and hydrazine hydrate shattered the reaction flask [Wischmeyer 1967]. Spontaneous ignition occurs when nitrous oxide and hydrazine are mixed [Mellor 8, Supp. 2:214(1967)]. Potassium and sodium dichromate react explosively with hydrazine [Mellor 11:234(1946-1947)]. Hydrazine hydrate reacts with stannous chloride to give stannous dihydrazinechloride, which decomposes explosively when heated [Mellor 7:430(1946-1947)]. Explodes during distillation if traces of air are present. Affected by UV and metal ion catalysis [Merck, 11th ed., 1989].
Hazard
Severe explosion hazard when exposed to
heat or by reaction with oxidizers. Toxic by ingestion, inhalation, and skin absorption; strong irritant
to skin and eyes; a confirmed carcinogen.
Health Hazard
Hydrazine is extremely destructive to the tissues of the mucous membranes and upper
respiratory tract, eyes, and skin. Skin contact with the liquid can result in severe burns;
hydrazine is readily absorbed through the skin, leading to systemic effects, which may
include damage to the liver, kidney, nervous system, and red blood cells. Hydrazine
vapor is irritating to the nose, throat, and respiratory tract, and inhalation of high
concentrations may be fatal as a result of spasm, inflammation, chemical pneumonitis,
and pulmonary edema. Symptoms of exposure may include a burning sensation,
coughing, wheezing, laryngitis, shortness of breath, headache, nausea, and vomiting.
Hydrazine vapor is extremely irritating to the eyes and can cause temporary blindness.
Eye contact with the liquid can result in severe burns and permanent damage. Hydrazine
is not considered to have adequate warning properties.
Hydrazine is listed by IARC in Group 2B "possible human carcinogen" and is classified
as a "select carcinogen" according to the criteria of the OSHA Laboratory Standard.Chronic exposure to subacute levels of hydrazine can cause lethargy, vomiting,
tremors, itching and burning of the eyes and skin, conjunctivitis, and contact
dermatitis. Hydrazine has been found to exhibit reproductive and developmental
toxicity in animal tests.
Brandgefahr
Flammable/combustible material. May be ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.
Flammability and Explosibility
Hydrazine is a flammable liquid (NFPA rating = 3) over a very broad range of vapor
concentrations (4.7 to 100%). Hydrazine may undergo autoxidation and ignite
spontaneously when brought in contact with porous substances such as rusty
surfaces, earth, wood, or cloth. Fires should be extinguished with water spray,
carbon dioxide, or dry chemical extinguishers.
Carcinogenicity
Hydrazine and hydrazine sulfate are reasonably anticipated to be human carcinogens based on sufficient evidence of carcinogenicity from studies in experimental animals.
Environmental Fate
Hydrazine can be found in the environment in small quantities
and is a component of tobacco smoke. However, hydrazine is
primarily an industrial chemical that enters the environment by
emissions from its use as an aerospace fuel and from industrial
facilities that manufacture, process, and/or use this chemical.
Treatment and disposal of wastes containing hydrazine also
contribute to environmental concentrations. However, hydrazine
rapidly degrades in the environment and is rarely
encountered outside the industrial setting.
Lager
work
with hydrazine should be conducted in a fume hood to prevent exposure by
inhalation, and splash goggles and impermeable gloves should be worn at all times
to prevent eye and skin contact. Hydrazine should be used only in areas free of
ignition sources. Hydrazine should be stored under nitrogen in containers placed in
secondary containers in areas separate from oxidizers and acids.
l?uterung methode
Hydrazine hydrate is dried by refluxing with an equal weight of KOH pellets for 3hours, then distilled from fresh solid NaOH or BaO in a current of dry N2. Use stainless steel or copper equipment. Hydrazine and its hydrates have VERY IRRITATING and TOXIC vapours and should be used in an efficient fume cupboard. Store in a well-stoppered vessel, preferably under N2. It is a reducing agent. [Schenk in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I pp 469-472 1963.]
Inkompatibilit?ten
Hydrazine is a highly reactive reducing agent that forms shock-sensitive, explosive
mixtures with many compounds. It explodes on contact with barium oxide, calcium
oxide, chromate salts, and many other substances. On contact with metal catalysts
(platinum black, Raney nickel, etc.), hydrazine decomposes to ammonia, hydrogen,
and nitrogen gases, which may ignite or explode.
Waste disposal
In the event of a spill, remove all ignition sources, soak up the hydrazine with a spill
pillow or absorbent material, place in an appropriate container, and dispose of
properly. Evacuation and cleanup using respiratory protection may be necessary in
the event of a large spill or release in a confined area.
Disposal Excess hydrazine and waste material containing this substance should be placed in
an appropriate container, clearly labeled, and handled according to your institution's
waste disposal guidelines. For more information on disposal procedures, see
Chapter 7 of this volume.
Hydrazin Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
