Chlordioxid Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
GELBROTES GAS MIT STECHENDEM GERUCH.
PHYSIKALISCHE GEFAHREN
Das Gas ist schwerer als Luft.
CHEMISCHE GEFAHREN
Kann beim Erhitzen, bei Exposition gegenüber Sonnenlicht, Schlag oder Funken explodieren. Starkes Oxidationsmittel. Reagiert sehr heftig mit brennbaren und reduzierenden Stoffen. Reagiert sehr heftig mit organischen Stoffen, Phosphor, Kaliumhydroxid und Schwefel. Feuer- und Explosionsgefahr. Reagiert mit Wasser unter Bildung von Salzsäure und Chlorsäure.
ARBEITSPLATZGRENZWERTE
TLV: 0,1 ppm (als TWA) 0,3 ppm (als STEL) (ACGIH 2005).
MAK: 0,1 ppm 0,28 mg/m?Spitzenbegrenzung: überschreitungsfaktor I(1); Schwangerschaft: Gruppe D (DFG 2006).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation.
INHALATIONSGEFAHREN
Eine gesundheitsschädliche Konzentration des Gases in der Luft wird beim Entweichen aus dem Behälter sehr schnell erreicht.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Die Substanz reizt stark die Augen, die Haut und die Atemwege. Inhalation des Gases kann zu Lungenödem führen (s.Anm.). Exposition weit oberhalb der Arbeitsplatzgrenzwerte kann zum Tod führen. Die Auswirkungen treten u.U. verzögert ein. ärztliche Beobachtung notwendig.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
Möglich sind Auswirkungen auf die Lunge mit nachfolgender chronischer Bronchitis.
LECKAGE
Gefahrenbereich verlassen! Fachmann zu Rate ziehen! Belüftung. Gas mit feinem Wassersprühstrahl niederschlagen. Persönliche Schutzausrüstung: Vollschutzanzug mit umgebungsluftunabhängigem Atemschutzgerät.
R-Sätze Betriebsanweisung:
R6:Mit und ohne Luft explosionsfähig.
R8:Feuergefahr bei Berührung mit brennbaren Stoffen.
R26:Sehr giftig beim Einatmen.
R34:Verursacht Verätzungen.
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.
S28:Bei Berührung mit der Haut sofort abwaschen mit viel . . . (vom Hersteller anzugeben).
S36/37/39:Bei der Arbeit geeignete Schutzkleidung,Schutzhandschuhe und Schutzbrille/Gesichtsschutz tragen.
S38:Bei unzureichender Belüftung Atemschutzgerät anlegen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S61:Freisetzung in die Umwelt vermeiden. Besondere Anweisungen einholen/Sicherheitsdatenblatt zu Rate ziehen.
Chemische Eigenschaften
Chlorine dioxide,CI02, is a yellow-reddish gas.It is a very effective bleaching and water treatment agent. Chlorine dioxide is preparedby the reaction of chlorine and sodium chlorite. It is quite unstable and is commonly prepared immediately before use.
Physikalische Eigenschaften
Yellow to red-yellow gas at room temperature; pungent chlorine-like odor; density 9.99 g/L at 11°C; liquefies to a reddish brown liquid at 11°C; liquid density 1.64 g/mL at 0°C; freezes at -59.5° C to red crystals (explodes); soluble in water, decomposes in hot water; soluble in alkalis and H
2SO
4.
Verwenden
Chlorine Dioxide is a gas used in bleaching and aging flour. it acts
on the flour almost instantly, resulting in improved color and dough
properties. because usage levels are low, the bleaching action is
limited.
synthetische
Chlorine dioxide is prepared by passing nitrogen dioxide through sodium chlorate packed in a column:
NaClO
3 + NO
2 → NaNO
3 + ClO
2 Also, it may be prepared by the reaction of chlorine with sodium chlorite:
2NaClO
2 + Cl
2 → 2ClO
2 + 2NaCl
Alternatively, it may be obtained by the treatment of sodium chlorate or potassium chlorate with sulfur dioxide and sulfuric acid:
2NaClO
3 + SO
2 + H
2SO
4 → 2ClO
2 + 2 NaHSO
4.
Vorbereitung Methode
Chlorine dioxide is manufactured from the oxidation of
chlorite or the reduction of chlorate. The latter method is
used for large-volume production and is carried out in
strongly acidic solution using reducing agents such as
NaCl, HCl, sulfur dioxide, and methanol.
Definition
An orange gas formed by the action
of concentrated sulfuric acid on potassium
chlorate. It is a powerful oxidizing
agent and its explosive properties in the presence of a reducing agent were used to
make one of the first matches. It is widely
used in the purification of water and as a
bleach in the flour and wood-pulp industry.
On an industrial scale an aqueous solution
of chlorine dioxide is made by
passing nitrogen dioxide up a tower
packed with a fused mixture of aluminum
oxide and clay, down which a solution of
sodium chlorate flows.
Hazard
Explodes when heated or by reaction with
organic materials. Very irritating to skin and mucous
membranes. Lower respiratory tract irritant. Broncitis.
Health Hazard
Chlorine dioxide is highly irritating to theeyes, nose, and throat. Inhalation can causecoughing, wheezing, respiratory distress, andcongestion in the lungs. Its toxicity inhumans is moderate to high. Its irritanteffects in humans can be intense at a con centration level of 5 ppm in air. A concen tration of 19 ppm of the gas inside a bleachtank caused the death of one worker (Elkins 1959). The chronic toxicity signs are mainlydyspnea and asthmatic bronchitis, and in cer tain cases irritation of the gastrointestinaltract. Ingestion of the liquid may cause som nolence and respiratory stimulation.
Brandgefahr
Nonflammable gas; however, it is highly
reactive and a strong oxidizing agent. Chlo rine dioxide explodes violently upon heating,
exposure to sunlight, contact with dust, or
when subjected to a spark. Detonation occurs
at concentrations above 10% in air in the
presence of an energy source or catalyst.
It undergoes violent reactions with organic
matter; explosion occurs when the mixture is
subjected to shock or a spark. It reacts spon taneously with sulfur or phosphorus, caus ing ignition and/or explosion. Liquid chlorine
dioxide may explode violently when mixed
with mercury, caustic potash, caustic soda, or
many metal hydrides. The gas reacts explo sively with fluorine and with difluoroamine
(Lawless and Smith 1968).
Sicherheitsprofil
Moderately toxic by
inhalation. Experimental reproductive
effects. Mutation data reported. An eye
irritant. A powerful explosive sensitive to
spark, impact, sunlight, or heating rapidly to
100℃. A powerful oxidzer. Concentrations
of greater than 10% in air are explosive.
Explodes on mixing with carbon monoxide,
hydrocarbons (e.g., butadiene, ethane, ethylene, methane, propane), fluoramines
(e.g., difluoramine, trifluoramine). Mtxtures
with hydrogen explode with sparking or
contact with platinum. Explodes on contact
with mercury, potassium hydroxide,
phosphorus pentachloride + chlorine.
Ignites or explodes on contact with nonmetals (e.g., phosphorus, sulfur, sugar).
Reacts violently with F2, NHF2. Reacts with
water or steam to produce toxic and
corrosive fumes of HCl. When heated to
decomposition it emits toxic fumes of Cl-.
See also CHLORINE.
mögliche Exposition
Chlorine dioxide is used in bleaching
cellulose pulp; bleaching flour; water purification; as a liquid sterilizer in an ultrasonic cleaner.
Versand/Shipping
UN/NA 9191 Chlorine dioxide, hydrate, frozen,
Hazard class: 5.1; Labels: 5.1-Oxidizer, 6.1-Poison
Inhalation. Explosive: It may only be shipped in the frozen
state and then only by private or contract motor carrier.
Inkompatibilitäten
Unstable in light. A powerful oxidizer.
Chlorine dioxide gas is explosive at concentrations over
10% and can be ignited by almost any form of energy,
including sunlight, heat (explosions can occur in air in
temperature above 130C), or sparks, shock, friction, or
concussion. This chemical reacts violently with dust, combustible materials; and reducing agents. Reacts violently
with mercury, phosphorus, sulfur, and many compounds,
causing fire and explosion hazard. Contact with water
forms perchloric and hydrochloric acid. Corrosive to
metals.
Waste disposal
Use large volume of concentrated solution of ferrous salt or bisulfite solution as reducing agent. Then neutralize and flush to sewer with
abundant water.
Chlordioxid Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
