Hydroxylamin Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
STARK HYGROSKOPISCHE WEISSE NADELN ODER FLOCKEN.
ARBEITSPLATZGRENZWERTE
TLV nicht festgelegt (ACGIH 2005).
MAK: Sensibilisierung der Haut; (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation, über die Haut und durch Verschlucken.
INHALATIONSGEFAHREN
Nur ungenügende Angaben vorhanden über die Geschwindigkeit, mit der eine gesundheitsschädliche Konzentration in der Luft beim Verdampfen bei 20°C erreicht wird.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Die Substanz reizt die Haut und die Atemwege und verätzt die Augen. Möglich sind Auswirkungen auf das Blut mit nachfolgender Methämoglobinbildung. Die Auswirkungen treten u.U. verzögert ein. ärztliche Beobachtung notwendig.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
Wiederholter oder andauernder Kontakt kann zu Hautsensibilisierung führen. Möglich sind Auswirkungen auf das Blut mit nachfolgender Methämoglobinbildung und Blutarmut.
LECKAGE
Verschüttetes Material in abdichtbaren Behältern sammeln; falls erforderlich durch Anfeuchten Staubentwicklung verhindern. Reste sorgfältig sammeln. An sicheren Ort bringen. Persönliche Schutzausrüstung: Atemschutzgerät, P2-Filter für schädliche Partikel.
R-Sätze Betriebsanweisung:
R5:Beim Erwärmen explosionsfähig.
R22:Gesundheitsschädlich beim Verschlucken.
R37/38:Reizt die Atmungsorgane und die Haut.
R41:Gefahr ernster Augenschäden.
R43:Sensibilisierung durch Hautkontakt möglich.
R48/22:Gesundheitsschädlich: Gefahr ernster Gesundheitsschäden bei längerer Exposition durch Verschlucken.
R50:Sehr giftig für Wasserorganismen.
S-Sätze Betriebsanweisung:
S23:Gas/Rauch/Dampf/Aerosol nicht einatmen(geeignete Bezeichnung(en) vom Hersteller anzugeben).
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36/37/39:Bei der Arbeit geeignete Schutzkleidung,Schutzhandschuhe und Schutzbrille/Gesichtsschutz tragen.
S47:Nicht bei Temperaturen über . . . °C aufbewahren (vom Hersteller anzugeben).
S61:Freisetzung in die Umwelt vermeiden. Besondere Anweisungen einholen/Sicherheitsdatenblatt zu Rate ziehen.
S22:Staub nicht einatmen.
Beschreibung
Hydroxylamine was first synthesized by Wilhem Clemens
Lossen in 1865 in the laboratory of Wilhelm Heinrich Heintz
while working in Halle. The Lossen synthesis originally generated
hydroxylamine in aqueous solution. Anhydrous hydroxylamine
was prepared later by Lobry de Bruyn and Crismer in
1891. The free base is extremely volatile, and industrial-scale
production has been fraught with problems, including large
explosions at facilities in the United States and Japan. Much of
the hydroxylamine produced and transported is in salt form or
as a dilute aqueous solution.
Chemische Eigenschaften
slightly yellow liquid
Physikalische Eigenschaften
White crystalline solid; orthogonal plates or needles; unstable; density 1.21g/cm3at 20°C; melts at 33°C; vaporizes at 58°C; very soluble in water, liquidammonia and lower alcohols; sparingly soluble in most other organic solvents;decomposes in hot water; pKa5.94 at 25°C.
Verwenden
Hydroxylamine is used as a reducing agent in photography, in
synthetic and analytical chemistry, as an antioxidant for fatty
acids and soaps, and as a dehairing agent for hides. In addition,
hydroxylamine is used in the production of cyclohexanone
oxime, an isomer of caprolactam, which is an intermediate in
the production of nylon-6. In the semiconductor industry,
hydroxylamine can be a component of a solution that dissolves
a photoresist following lithography. Hydroxylamine can also
be used to selectively cleave asparaginyl-glycine peptide bonds.
synthetische
Hydroxylamine is unstable as a free base. It is prepared from hydroxy-lamine hydrochloride, NH2OH?HCl, which is obtained by electrolytic reduc-tion of ammonium chloride solution. The hydrochloride undergoes alkalinedecomposition to hydroxylamine, which is collected by vacuum distillation.
Definition
ChEBI: The simplest hydroxylamine, consisting of ammonia bearing a hydroxy substituent. It is an intermediate in the biological nitrification by microbes like bacteria.
Allgemeine Beschreibung
Odorless white crystalline solid. Sinks and mixes with water.
Air & Water Reaktionen
Decomposes rapidly at room temperature or when dissolved in hot water by internal oxidation-reduction. Reacts with water or steam to produce heat and corrosive liquids.
Reaktivität anzeigen
HYDROXYLAMINE is a white solid, thermally unstable, decomposes rapidly at room temperature or when dissolved in hot water by internal oxidation-reduction. HYDROXYLAMINE should be stored below 10° C [Bailar, 1973, vol. 2, p. 272]. Explosive reaction with strong oxidizers (chromium trioxide, potassium dichromate) or powdered zinc upon heat. Reaction with zinc or calcium produces explosive bishydroxylamides. HYDROXYLAMINE ignites on contact with cupric sulfate, alkali metals (sodium, potassium), oxidants (e.g., barium oxide, barium peroxide, lead dioxide, potassium permanganate, chlorine), phosphorus trichloride and pentachloride. HYDROXYLAMINE reacts vigorously with hypochlorites, pyridine, carbonyls [Sax, 9th ed., 1996, p. 1875]. On contact with organic materials in thin layer (e.g., crystals on filter paper), HYDROXYLAMINE may ignite spontaneously in air. HYDROXYLAMINE explodes when heated above 70° C [Brauer, 1963, vol. 1, p. 502]. During a distillation process, an explosion occurred. Potassium hydroxide is thought to be involved in the explosion. Employees in the plant complained of chest pains and suffered chemical burns. Five people were killed by the explosion.
Hazard
Decomposes rapidly at room temperature,
violently when heated, detonates in flame-heated
test tube. Irritant to tissue.
Health Hazard
INHALATION: Moderately toxic by inhalation and oral routes with the following symptoms possible: headache, vertigo, tinnitus, dyspnea, nausea and vomiting, cyanosis, proteinuria and hematuria, jaundice, restlessness, and convulsion. Methemoglobinemia has been reported. EYES: Corrosive - highly irritating. SKIN: Irritating or corrosive to skin. INGESTION: Moderately toxic by inhalation and oral routes with the following symptoms possible; headache, vertigo, tinnitus, dyspnea, nausea and vomiting, cyanosis, proteinuria and hematuria, jaundice, restlessness, and convulsion. Methemoglobinemia has been reported.
Kontakt-Allergie
Hydroxylamine and its salts are used in various
branches of industry, as reducing agents in color film
developers or as reagents in laboratories.
Carcinogenicity
Carcinogenicity of hydroxylamine and
its salts has not been demonstrated. Several
studies have shown a decreased incidence of
spontaneous mammary tumors in mice exposed
to the sulfate and hydrochloride.3–7 There was
some indication of an increase in the incidence
of spontaneous mammary tumors when the
sulfate was administered to older animals
whose mammary glands were already well
developed.
Environmental Fate
The large-scale production and use of hydroxylamine may
result in its release to the environment through various waste
streams. Hydroxylamine will exist solely as a vapor in the
ambient atmosphere, and will be degraded in the atmosphere
by reaction with photochemically produced hydroxyl radicals;
the half-life for this reaction in air is estimated to be 18 h.
Abiotic degradation of hydroxylamine by photochemically
produced peroxy radicals is an important environmental fate
process in surface waters, with the half-life of the reaction
measured at approximately 2 h. An estimated bioconcentration
factor of 3 suggests that the potential for bioconcentration in
aquatic organisms is low. If released terrestrially, hydroxylamine
will most likely exist in its protonated form due to its
pKa of 5.94; the protonated form is nonvolatile. Koc estimates
of 14 for hydroxylamine suggest that it may have very high
mobility in soil.
läuterung methode
Crystallise it from n-butanol at -10o, collect it by vacuum filtration and wash it with cold diethyl ether. Harmful vapours. [Hurd Inorg Synth I 87 1939, Semon in Org Synth Coll Vol I 318 1932.]
Hydroxylamin Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
