Dichlormethan Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
FARBLOSE FLüSSIGKEIT MIT CHARAKTERISTISCHEM GERUCH.
PHYSIKALISCHE GEFAHREN
Die Dämpfe sind schwerer als Luft. Fließen, Schütten o.ä. kann zu elektrostatischer Aufladung führen.
CHEMISCHE GEFAHREN
Bei Kontakt mit heißen Gegenständen oder Flammen Zersetzung unter Bildung giftiger und ätzender Rauche. Reagiert heftig mit Metallen wie Aluminium- und Magnesiumpulver, starken Basenund starken Oxidationsmitteln. Feuer- und Explosionsgefahr. Greift einige Kunststoff-, Gummi- und Beschichtungsarten an.
ARBEITSPLATZGRENZWERTE
TLV: 50 ppm (als TWA) Krebskategorie A3 (bestätigte krebserzeugende Wirkung beim Tier mit unbekannter Bedeutung für den Menschen); BEI vorhanden (ACGIH 2005).
MAK: Krebserzeugend Kategorie 3A; (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation und durch Verschlucken.
INHALATIONSGEFAHREN
Beim Verdampfen bei 20 °C kann sehr schnell eine gesundheitsschädliche Kontamination der Luft eintreten.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Die Substanz reizt die Augen, die Haut und die Atmungsorgane. Exposition kann Bewusstseinstrübung verursachen. Exposition kann zur Bildung von Carboxyhämoglobin führen.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
Wiederholter oder andauernder Hautkontakt kann Dermatitis hervorrufen. Möglich sind Auswirkungen auf Zentralnervensystemund Leber. Möglicherweise krebserzeugend für den Menschen.
LECKAGE
Persönliche Schutzausrüstung: Atemschutzfilter für organische Gase und Dämpfe. NICHT in die Umwelt gelangen lassen. Belüftung. Ausgelaufene Flüssigkeit möglichst in abdichtbaren Behältern sammeln. Reste mit Sand oder inertem Absorptionsmittel aufnehmen und an einen sicheren Ort bringen.
R-Sätze Betriebsanweisung:
R40:Verdacht auf krebserzeugende Wirkung.
R39/23/24/25:Giftig: ernste Gefahr irreversiblen Schadens durch Einatmen, Berührung mit der Haut und durch Verschlucken.
R23/24/25:Giftig beim Einatmen, Verschlucken und Berührung mit der Haut.
R11:Leichtentzündlich.
S-Sätze Betriebsanweisung:
S23:Gas/Rauch/Dampf/Aerosol nicht einatmen(geeignete Bezeichnung(en) vom Hersteller anzugeben).
S24/25:Berührung mit den Augen und der Haut vermeiden.
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S16:Von Zündquellen fernhalten - Nicht rauchen.
S7:Behälter dicht geschlossen halten.
Aussehen Eigenschaften
CH2Cl2.
Farblose, süßlich riechende Flüssigkeit
Gefahren für Mensch und Umwelt
Gefährliche Reaktion z.B. mit Alkali- und Erdalkalimetallen sowie mit starken Basen.
Verschlucken verursacht Übelkeit und Erbrechen. Nach Resorption großer Mengen treten zentralnervöse Störungen, Störung der Atem- und Herztätigkeit sowie Leber- und Nierenschäden auf.
Kann möglicherweise Krebs erzeugen.
Wassergefährdender Stoff (WGK 2).
Schutzmaßnahmen und Verhaltensregeln
Im Abzug arbeiten! Dampf nicht einatmen. Berührung mit den Augen und der Haut vermeiden.
Latex- und Neoprenhandschuhe sind
nicht beständig! Höchstens als sehr kurzzeitigen Spritzschutz verwenden.
Verhalten im Gefahrfall
Kleine Mengen im Abzug verdampfen lassen. Verschüttete größere Mengen mit Absorptionsmaterial (z. B. Rench Rapid) aufnehmen. Der Entsorgung zuführen.
Brände mit CO
2-Löscher bekämpfen. Atemschutz: Kombinationsfilter ABEK.
Erste Hilfe
Nach Hautkontakt: Mit reichlich Wasser und Seife abwaschen.
Nach Augenkontakt: Mit viel Wasser mindestens 15 Minuten bei geöffnetem Lidspalt spülen. Augenarzt!
Nach Einatmen: Frischluft. Arzt.
Nach Verschlucken: Wasser trinken; kein Erbrechen. Arzt!
Nach Kleidungskontakt: Kontaminierte Kleidung ausziehen.
Ersthelfer: siehe gesonderten Anschlag
Sachgerechte Entsorgung
Als Sondermüll (halogenhaltige Lösungsmittel) entsorgen.
Beschreibung
Dichloromethane is a colorless liquid with an ethereal, but penetrating odor. Its miscibility in alcohol and ether and slight solubility in water has made it an ideal solvent and otherwise extremely versatile chemical. It has been used industrially (solvent and paint remover), as a drug (inhalation anesthetic) and as an agricultural chemical (growth regulator and fertilizer). It is narcotic in high concentrations and carcinogenic. Inhalation exposure to this substance irritates the nose and throat and affects the central nervous system.
Chemische Eigenschaften
Dichloromethane is a colorless liquid with a mild, sweet odor. It does not occur naturally in the environment. It is made from methane gas or wood alcohol. Industrial uses of dichloromethane are extensive, as a solvent in paint strippers, as a propellant in aerosols, and as a process solvent in the manufacturing of drugs. dichloromethane is also used as a metal cleaning and fi nishing solvent, and it is approved as an extraction solvent for spices and hops. Exposure to dichloromethane occurs in workplaces by breathing fumes from paint strippers that contain it (check the label), breathing fumes from aerosol cans that use it (check the label), and breathing contaminated air near waste sites.
Physikalische Eigenschaften
Clear, colorless liquid with a sweet, penetrating, ethereal odor. Leonardos et al. (1969) determined
an odor threshold concentration of 214.0 ppm
v. The average least detectable odor threshold
concentrations of technical grade methylene chloride in water at 60 °C and in air at 40 °C were 5.6
and 24 mg/L, respectively (Alexander et al., 1982).
Verwenden
Dichloromethane, also called methylene chloride, is widely used as a solvent, as a degreasing and cleaning reagent, in paint removers, and in extractions oforganic compounds from water for analyses.
Vorbereitung Methode
Dichloromethane was first prepared by Regnault in 1840 by the chlorination of methyl chloride in sunlight. It became an industrial chemical of importance during the Second World War. Two commercial processes are currently used for the production of dichloromethane—hydrochlorination of methanol and direct chlorination of methane (Rossberg et al., 1986; Holbrook, 1993). The predominant method of manufacturing dichloromethane uses as a first step the reaction of hydrogen chloride and methanol to give methyl chloride. Excess methyl chloride is then mixed with chlorine and reacts to give dichloromethane, with chloroform and carbon tetrachloride as co-products. This reaction is usually carried out in the gas phase thermally but can also be performed catalytically or photolytically. At low temperature and high pressure, the liquid-phase process is capable of giving high selectivity for dichloromethane (Rossberg et al., 1986; Holbrook, 1993).
Reaktionen
Methylene chloride reacts violently in the presence of alkali or alkaline earth metals and will hydrolyze to formaldehyde in the presence of an aqueous base. Alkylation reactions occur at both functions, thus di-substitutions result.
Allgemeine Beschreibung
Dichloromethane has been tested as a solvent medium for the dipyridine-chromium(VI) oxide. Solubility was reported to be 12.5g/100ml. Role of quantity of TiO
2 loading on activated carbon support employed in the photodecomposition of dichloromethane has been investigated.
Air & Water Reaktionen
Methylene chloride is a colourless liquid with a mild, sweet odour. Somewhat water soluble. Subject to slow hydrolysis which is accelerated by light.
Reaktivität anzeigen
Dichloromethane reacts vigorously with active metals such as lithium, sodium and potassium, and with strong bases such as potassium tert-butoxide. Dichloromethane is incompatible with strong oxidizers, strong caustics and chemically active metals such as aluminum or magnesium powders. The liquid will attack some forms of plastic, rubber and coatings. Dichloromethane reacts with sodium-potassium alloy, (potassium hydrogen + N-methyl-N-nitrosurea), nitrogen tetraoxide and liquid oxygen. Dichloromethane also reacts with titanium. On contact with water Dichloromethane corrodes iron, some stainless steels, copper and nickel. Dichloromethane is incompatible with alkali metals. Dichloromethane is incompatible with amines, zinc and alloys of aluminum, magnesium and zinc. Dichloromethane is liable to explode when mixed with dinitrogen pentaoxide or nitric acid. Mixtures of Dichloromethane in air with methanol vapor are flammable.
Hazard
Toxic. A narcotic. Central nervous systemimpairment and carboxyhemoglobinemia. Possiblecarcinogen.
Health Hazard
Dichloromethane is classified as only slightly toxic by the oral and inhalation routes.
Exposure to high concentrations of dichloromethane vapor (>500 ppm for 8 h) can
lead to lightheadedness, fatigue, weakness, and nausea. Contact of the compound
with the eyes causes painful irritation and can lead to conjunctivitis and corneal
injury if not promptly removed by washing. Dichloromethane is a mild skin irritant,
and upon prolonged contact (e.g., under the cover of clothing or shoes) can cause
burns after 30 to 60 min exposure.
Dichloromethane is not teratogenic at levels up to 4500 ppm or embryotoxic in rats
and mice at levels up to 1250 ppm.
Brandgefahr
Special Hazards of Combustion Products: Dissociation products generated in a fire may be irritating or toxic.
Flammability and Explosibility
Noncombustible. Dichloromethane vapor concentrated in a confined or poorly ventilated area can be ignited with a high-energy spark, flame, or high-intensity heat source.
Chemische Reaktivität
Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.
Sicherheitsprofil
Confirmed carcinogen
with experimental carcinogenic and
tumorigenic data. Poison by intravenous
route. Moderately toxic by ingestion,
subcutaneous, and intraperitoneal routes.
Mildly toxic by inhalation. Human systemic
effects by ingestion and inhalation:
paresthesia, somnolence, altered sleep time, convulsions, euphoria, and change in cardlac
rate. An experimental teratogen.
Experimental reproductive effects. An eye
and severe skin irritant. Human mutation
data reported. It is flammable in the range of
12-19% in air but ignition is difficult. It will
not form explosive mixtures with air at
ordinary temperatures. Mixtures in air with
methanol vapor are flammable. It will form
explosive mixtures with an atmosphere
having a high oxygen content, in liquid O2,
N2O4, K, Na, NaK. Explosive in the form
of vapor when exposed to heat or flame.
Reacts violently with Li, NaK, potassiumtert-
butoxide, (KOH + N-methyl-Nnitrosourea).
It can be decomposed by
contact with hot surfaces and open flame,
and then yield toxic fumes that are irritating
and give warning of their presence. When
heated to decomposition it emits highly
toxic fumes of phosgene and Cl-.
mögliche Exposition
Methylene chloride is used mainly as
a low-temperature extractant of substances which are
adversely affected by high temperature. It can be used
as a solvent for oil, fats, waxes, bitumen, cellulose acetate;
and esters. It is also used as a paint remover;
as a degreaser; and in aerosol propellants
Carcinogenicity
Dichloromethane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Versand/Shipping
UN1593Dichloromethane, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials
läuterung methode
Shake it with portions of conc H2SO4 until the acid layer remains colourless, then wash with water, aqueous 5% Na2CO3, NaHCO3 or NaOH, then water again. Pre-dry with CaCl2, and distil it from CaSO4, CaH2 or P2O5. Store it away from bright light in a brown bottle with Linde type 4A molecular sieves, in an atmosphere of dry N2. Other purification steps include washing with aqueous Na2S2O3, passage through a column of silica gel, and removal of carbonyl-containing impurities as described under Chloroform. It has also been purified by treatment with basic alumina, distillation, and stored over molecular sieves under nitrogen [Puchot et al. J Am Chem Soc 108 2353 1986]. Dichloromethane from Japanese sources contained MeOH as stabiliser which is not removed by distillation. It can, however, be removed by standing over activated 3A Molecular Sieves (note that 4A Sieves cause the development of pressure in bottles), passed through activated Al2O3 and distilled [Gao et al. J Am Chem Soc 109 5771 1987]. It has been fractionated through a platinum spinning band column, degassed, and distilled onto degassed molecular sieves Linde 4A (heated under high vacuum at over 450o until the pressure readings reached the low values of 10-6 mm, ~1-2hours ). Stabilise it with 0.02% of 2,6-di-tert-butyl-p-cresol [Mohammad & Kosower J Am Chem Soc 93 2713 1971]. [Beilstein 1 IV 35.] Rapid purification: Reflux over CaH2 (5% w/v) and distil it. Store it over 4A molecular sieves.
Inkompatibilitäten
Incompatible with strong oxidizers,
caustics; chemically active metals, such as aluminum,
magnesium powders; potassium, lithium, and sodium;
concentrated nitric acid causing fire and explosion hazard.
Contact with hot surfaces or flames causes decomposition
producing fumes of hydrogen chloride and phosgene gas.
Attacks some forms of plastics, rubber and coatings.
Attacks metals in the presence of moisture.
Waste disposal
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform to EPA regulations
governing storage, transportation, treatment, and waste
disposal. Incineration, preferably after mixing with
another combustible fuel; care must be exercised to
assure complete combustion to prevent the formation
of phosgene; an acid scrubber is necessary to remove the
halo acids produced.
Dichlormethan Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
DI-2-PYRIDYL THIONOCARBONATE
(4-IODOPHENYL)ACETONE
3-Bromophenyl isocyanate
Benzoylisocyanat
2-Amino-4,6-bis(difluoromethoxy)pyrimidine
4,5-Dimethyl-1,3,2-dioxathiolan-2-oxid
Dimethylheptandioat
Doxorubicin
BIS(TRIMETHYLSILYL)PEROXIDE
(1,1-DIMETHYL-PROPYL)-HYDRAZINE
TERT-BUTYL N-(2-HYDROXYETHYL)CARBAMATE
3,5-DIBROMO-1H-1,2,4-TRIAZOLE
Cefradine
1,4-Dihydro-3H-2-benzopyran-3-on
1,3-Diphenylharnstoff
4-Methylbenzyl isocyanate
Phenylmethylchloracetat
2,5-Dichlor-p-xylol
DIBUTYLBORON TRIFLUOROMETHANESULFONATE
2-Amino-2,3-dimethylbutyramide
4-Bromthiophen-2-carbaldehyd
Tiotropium bromide
p-Phenylbenzoylchlorid
2-Naphthoylchlorid
metaclazepam
2-(2-Butoxyethoxy)ethylacetat
Tricyclo[3.3.1.13,7]decan-1-carbonylchlorid
4-DIMETHYLAMINOBENZOYL CHLORIDE
2-CHLORO-5-(TRIFLUOROMETHYL)PHENYL ISOCYANATE
dimethyl hexadecyl ammoium butayl sulfate
3-METHOXYPHENYLACETYL CHLORIDE
2-Methylpropylisocyanid
1,2-Epoxycyclopentan
Bis(acetonitril)dichloropalladium
2-Bromo-5-nitro-4-picoline
6-Amino-8-(((aminocarbonyl)oxy)-methyl)-1,1a,2,8,8a,8b-hexahydro-8a-methoxy-5-methylazirino-(2',3': 3,4)pyrrolo(1,2-a)indol-4,7-dion,(1aS-(1a alpha, 8 beta, 8a alpha,8b alpha))-
1-Naphthoylchlorid
PYRROLIDINE-1-SULFONYL CHLORIDE
(S)-(+)-Methyl glycidyl ether
Benzoylferrocen
