ChemicalBook
Chinese english Germany Japanese Korea

Benzol Produkt Beschreibung

Benzene Struktur
71-43-2
CAS-Nr.
71-43-2
Bezeichnung:
Benzol
Englisch Name:
Benzene
Synonyma:
PHENE;BENZOL;Benzen;Fenzen;BENZENE;Benzeen;Benzole;Benzolo;Annulene;BenzeneI
CBNumber:
CB6854153
Summenformel:
C6H6
Molgewicht:
78.11
MOL-Datei:
71-43-2.mol

Benzol Eigenschaften

Schmelzpunkt:
5.5 °C(lit.)
Siedepunkt:
80 °C(lit.)
Dichte
0.874 g/mL at 25 °C(lit.)
Dampfdichte
2.77 (vs air)
Dampfdruck
166 mm Hg ( 37.7 °C)
Brechungsindex
n20/D 1.501(lit.)
Flammpunkt:
12 °F
storage temp. 
0-6°C
Löslichkeit
Miscible with alcohol, chloroform, dichloromethane, diethyl ether, acetone and acetic acid.
pka
43(at 25℃)
Aggregatzustand
Liquid
Farbe
APHA: ≤10
Relative polarity
0.111
Geruch (Odor)
Paint-thinner-like odor detectable at 12 ppm
Explosionsgrenze
1.4-8.0%(V)
Wasserlöslichkeit
0.18 g/100 mL
maximale Wellenlänge (λmax)
λ: 280 nm Amax: 1.0
λ: 290 nm Amax: 0.15
λ: 300 nm Amax: 0.06
λ: 330 nm Amax: 0.02
λ: 350-400 nm Amax: 0.01
Merck 
14,1066
BRN 
969212
Henry's Law Constant
10.4 at 45.00 °C, 11.4 at 50.00 °C, 13.3 at 55.00 °C, 14.5 at 60.00 °C, 16.8 at 65.00 °C, 19.2 at 70.00 °C (static headspace-GC, Park et al., 2004)
Expositionsgrenzwerte
TLV-TWA 10 ppm (~32 mg/m3) (ACGIH and OSHA); ceiling 25 ppm (~80 mg/m3) (OSHA and MSHA); peak 50 ppm (~160 mg/m3)/10 min/8 h (OSHA); carcinogenicity: Suspected Human Carcinogen (ACGIH), Human Sufficient Evidence (IARC).
Stabilität:
Stable. Substances to be avoided include strong oxidizing agents, sulfuric acid, nitric acid, halogens. Highly flammable.
InChIKey
UHOVQNZJYSORNB-UHFFFAOYSA-N
CAS Datenbank
71-43-2(CAS DataBase Reference)
NIST chemische Informationen
Benzene(71-43-2)
EPA chemische Informationen
Benzene(71-43-2)
Sicherheit
  • Risiko- und Sicherheitserklärung
  • Gefahreninformationscode (GHS)
Kennzeichnung gefährlicher F,T
R-Sätze: 45-46-11-36/38-48/23/24/25-65-39/23/24/25-23/24/25
S-Sätze: 53-45-36/37-16-7
RIDADR  UN 1114 3/PG 2
WGK Germany  3
RTECS-Nr. CY1400000
3-10
Selbstentzündungstemperatur 560 °C
TSCA  Yes
HSCode  2902 20 00
HazardClass  3
PackingGroup  II
Giftige Stoffe Daten 71-43-2(Hazardous Substances Data)
Toxizität LD50 orally in young adult rats: 3.8 ml/kg (Kimura)
Bildanzeige (GHS)
Alarmwort Achtung
Gefahrenhinweise
Code Gefahrenhinweise Gefahrenklasse Abteilung Alarmwort Symbol P-Code
H225 Flüssigkeit und Dampf leicht entzündbar. Entzündbare Flüssigkeiten Kategorie 2 Achtung P210,P233, P240, P241, P242, P243,P280, P303+ P361+P353, P370+P378,P403+P235, P501
H302 Gesundheitsschädlich bei Verschlucken. Akute Toxizität oral Kategorie 4 Warnung P264, P270, P301+P312, P330, P501
H304 Kann bei Verschlucken und Eindringen in die Atemwege tödlich sein. Aspirationsgefahr Kategorie 1 Achtung
H315 Verursacht Hautreizungen. Hautreizung Kategorie 2 Warnung P264, P280, P302+P352, P321,P332+P313, P362
H319 Verursacht schwere Augenreizung. Schwere Augenreizung Kategorie 2 Warnung P264, P280, P305+P351+P338,P337+P313P
H336 Kann Schläfrigkeit und Benommenheit verursachen. Spezifische Zielorgan-Toxizität (einmalige Exposition) Kategorie 3 (Schläfrigkeit und Benommenheit) Warnung P261, P271, P304+P340, P312,P403+P233, P405, P501
H340 Kann genetische Defekte verursachen. Keimzellmutagenität Kategorie 1B Achtung
H350 Kann Krebs verursachen. Karzinogenität Kategorie 1A Achtung
H361 Kann vermutlich die Fruchtbarkeit beeinträchtigen oder das Kind im Mutterleib schädigen. Reproduktionstoxizität Kategorie 2 Warnung P201, P202, P281, P308+P313, P405,P501
H370 Schädigt die Organe. Spezifische Zielorgan-Toxizität (einmalige Exposition) Kategorie 1 Achtung P260, P264, P270, P307+P311, P321,P405, P501
H372 Schädigt bei Hautkontakt und Verschlucken die Organe bei längerer oder wiederholter Exposition. Spezifische Zielorgan-Toxizität (wiederholte Exposition) Kategorie 1 Achtung P260, P264, P270, P314, P501
H373 Kann die Organe schädigen bei längerer oder wiederholter Exposition. Spezifische Zielorgan-Toxizität (wiederholte Exposition) Kategorie 2 Warnung P260, P314, P501
H411 Giftig für Wasserorganismen, mit langfristiger Wirkung. Langfristig (chronisch) gewässergefährdend Kategorie 2
H412 Schädlich für Wasserorganismen, mit langfristiger Wirkung. Langfristig (chronisch) gewässergefährdend Kategorie 3 P273, P501
Sicherheit
P201 Vor Gebrauch besondere Anweisungen einholen.
P210 Von Hitze, heißen Oberflächen, Funken, offenen Flammen und anderen Zündquellenarten fernhalten. Nicht rauchen.
P260 Dampf/Aerosol/Nebel nicht einatmen.
P273 Freisetzung in die Umwelt vermeiden.
P280 Schutzhandschuhe/Schutzkleidung/Augenschutz tragen.
P311 GIFTINFORMATIONSZENTRUM/Arzt anrufen.
P331 KEIN Erbrechen herbeiführen.
P301+P310 BEI VERSCHLUCKEN: Sofort GIFTINFORMATIONSZENTRUM/Arzt/... (geeignete Stelle für medizinische Notfallversorgung vom Hersteller/Lieferanten anzugeben) anrufen.
P303+P361+P353 BEI BERÜHRUNG MIT DER HAUT (oder dem Haar): Alle kontaminierten Kleidungsstücke sofort ausziehen. Haut mit Wasser abwaschen oder duschen.
P308+P313 BEI Exposition oder falls betroffen: Ärztlichen Rat einholen/ärztliche Hilfe hinzuziehen.
P370+P378 Bei Brand: zum Löschen verwenden.
P403+P235 An einem gut belüfteten Ort aufbewahren. Kühl halten.

Benzol Chemische Eigenschaften,Einsatz,Produktion Methoden

ERSCHEINUNGSBILD

FARBLOSE FLüSSIGKEIT MIT CHARAKTERISTISCHEM GERUCH.

PHYSIKALISCHE GEFAHREN

Die Dämpfe sind schwerer als Luft und können sich am Boden ausbreiten. Fernzündung möglich. Fließen, Schütten o.ä. kann zu elektrostatischer Aufladung führen.

CHEMISCHE GEFAHREN

Reagiert heftig mit Oxidationsmitteln, Salpetersäure, Schwefelsäure und Halogenen. Feuer- und Explosionsgefahr! Greift Kunststoff und Gummi an.

ARBEITSPLATZGRENZWERTE

TLV: 0.5 ppm (als TWA); 2.5 ppm (als STEL); Hautresorption; Krebskategorie A1(bestätigte krebserzeugende Wirkung beim Menschen); BEI vorhanden (ACGIH 2005).
MAK: Hautresorption; Krebserzeugend Kategorie 1; Keimzellmutagen Kategorie 3A; (DFG 2005).

AUFNAHMEWEGE

Aufnahme in den Körper durch Inhalation, über die Haut und durch Verschlucken.

INHALATIONSGEFAHREN

Beim Verdampfen dieser Substanz bei 20 °C tritt sehr schnell eine gesundheitsschädliche Kontamination der Luft ein.

WIRKUNGEN BEI KURZZEITEXPOSITION

WIRKUNGEN BEI KURZZEITEXPOSITION:
Die Substanz reizt die Augen, die Haut und die Atmungsorgane. Verschlucken kann zur Aufnahme in der Lunge führen; Gefahr der Aspirationspneumonie. Möglich sind Auswirkungen auf das zentrale Nervensystem mit nachfolgender Bewusstseinstrübung. Exposition weit oberhalb der Arbeitsplatzgrenzwerte kann zu Bewusstlosigkeit und zum Tod führen.

WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION

Die Flüssigkeit entfettet die Haut. Möglich sind Auswirkungen auf Knochenmarkund Immunsystem. Führt zu Abnahme der Blutzellen. Krebserzeugend für den Menschen.

LECKAGE

Zündquellen entfernen. Ausgelaufene Flüssigkeit möglichst in abdichtbaren Behältern sammeln. Reste mit Sand oder inertem Absorptionsmittel aufnehmen und an einen sicheren Ort bringen. NICHT in die Kanalisation spülen! NICHT in die Umwelt gelangen lassen. Persönliche Schutzausrüstung: Vollschutzanzug mit umgebungsluftunabhängigem Atemschutzgerät.

R-Sätze Betriebsanweisung:

R45:Kann Krebs erzeugen.
R46:Kann vererbbare Schäden verursachen.
R11:Leichtentzündlich.
R36/38:Reizt die Augen und die Haut.
R48/23/24/25:Giftig: Gefahr ernster Gesundheitsschäden bei längerer Exposition durch Einatmen, Berührung mit der Haut und durch Verschlucken.
R65:Gesundheitsschädlich: kann beim Verschlucken Lungenschäden verursachen.
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.

S-Sätze Betriebsanweisung:

S53:Exposition vermeiden - vor Gebrauch besondere Anweisungen einholen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.

Aussehen Eigenschaften

C6H6. Wasserunlösliche, farblose, charakteristisch riechende Flüssigkeit.

Gefahren für Mensch und Umwelt

Leichtentzündlich. Gefährliche Reaktionen mit starken Oxidationsmitteln oder mit Leichtmetallen in Gegenwart von Chlorkohlenwasserstoffen.

Giftig beim Einatmen, Verschlucken und bei Berührung mit der Haut. Gefahr ernster Gesundheitsschäden bei längerer Exposition.
Benzol zeigt bei akuter oder chronischer Aufnahme unterschiedliche Wirkungen: Höhere Dampfkonzentationen führen zu einer starken Depression des zentralen Nervensystems, zunächst treten jedoch Euphorie und Erregung auf. Danach folgen je nach Konzentration und Einwirkungszeit Kopfschmerzen, Schwindel, unregelmäßiges Sprechen und auch Bewußtlosigkeit. Höhere Konzentrationen sind nach kurzer Zeit tödlich. Bei rechtzeitiger Frischluftzufuhr bleiben keine Schäden zurück. Flüssiges Benzol reizt die Haut und Schleimhäute und wirkt entfettend auf die Haut. Benzol wird leicht durch die Haut aufgenommen! Bei Verschlucken folgen Magenschmerzen und bei verzögerter Entfernung auch Störungen des zentralen Nervensystems.
Die chronische Einwirkung führt nach langer, symptomfreierLatenzzeit zu Schädigungen der Blutbildungsorgane und Bildung von Krebsgewebe.
Stark wassergefährdender Stoff (WGK 3).

Schutzmaßnahmen und Verhaltensregeln

Im Abzug arbeiten! Exposition vermeiden. Von Zündquellen fernhalten. Wenn möglich, Ersatzstoffe verwenden.
Schutzhandschuhe aus Latex und Neopren sind nicht gegen Benzol beständig (nur als sehr kurzzeitiger Spritzschutz verwendbar).

Verhalten im Gefahrfall

Kleine Spritzer im Abzug verdampfen lassen, größere Mengen mit Absorptionsmaterial (Rench-Rapid) aufnehmen und entsorgen. Dämpfe nicht einatmen. Atemschutz: Kombinationsfilter ABEK.
Brände mit CO2-Löscher bekämpfen!

Erste Hilfe

Nach Hautkontakt: Mit viel Wasser und Seife abwaschen.
Nach Augenkontakt: Mit Wasser mindestens 15 Minuten bei geöffnetem Lidspalt ausspülen. Augenarzt!
Nach Einatmen: Frischluft. Arzt!
Nach Verschlucken: Paraffinöl verabreichen. Erbrechen vermeiden. Arzt!
Nach Kleidungskontakt: Kontaminierte Kleidung sofort ausziehen.
Ersthelfer: siehe gesonderten Anschlag

Sachgerechte Entsorgung

Als Sondermüll (halogenfreie Lösungsmittel) entsorgen.

Beschreibung

Benzene is a colorless, volatile, highly flammable liquid that is used extensively in the chemical industry and received wide interest in the early days of organic chemistry.
Because of its structure, benzene is a very stable organic compound. It does not readily undergo addition reactions. Addition reactions involving benzene require high temperature, pressure, and special catalysts. The most common reactions involving benzene involve substitution reactions. Numerous atoms and groups of atoms may replace a hydrogen atom or several hydrogen atoms in benzene. Th ree important types of substitution reactions involving benzene are alkylation, halogenation, and nitration. In alkylation, an alkyl group or groups substitute for hydrogen(s).

Chemische Eigenschaften

Benzene,C6H6, also known as benzol, phenyl hydride, phene, cyclohexatriene and coal naptha,is a colorless,flammable liquid. It is an aromatic hydrocarbon that boils at 80.1 DC. It is used as a solvent and an intermediate in manufacturing organic compounds such as styrene and phenol.

Chemische Eigenschaften

Benzene is a colorless, flammable liquid with a pleasant odor. It is used as a solvent in many areas of industries, such as rubber and shoe manufacturing, and in the production of other important substances, such as styrene, phenol, and cyclohexane. It is essential in the manufacture of detergents, pesticides, solvents, and paint removers. It is present in fuels such as gasoline up to the level of 5%.

Chemische Eigenschaften

Benzene is a clear, volatile, colorless, highly flammable liquid with a pleasant, characteristic odor.

Physikalische Eigenschaften

Clear, colorless to light yellow watery liquid with an aromatic, musty, phenolics or gasoline-like odor. At 40 °C, an odor threshold concentration of 190 μg/L in air was determined by Young et al. (1996). An odor threshold of 4.68 ppmv was determined by Leonardos et al. (1969). A detection odor threshold concentration of 108 mg/m3 (34 ppmv) was reported by Punter (1983). The average least detectable odor threshold concentrations in water at 60 °C and in air at 40 °C were 0.072 and 0.5 mg/L, respectively (Alexander et al., 1982).

Occurrence

Detectable levels of benzene have been found in a number of soft drinks that contain either a sodium or potassium benzoate preservative and ascorbic acid, and 'diet' type products containing no added sugar are reported to be particularly likely to contain benzene at detectable levels. Surveys carried out in the USA, the UK and Canada have all confirmed that a small proportion of these products may contain low levels of benzene. For example, in a survey of 86 samples analysed by the FDA between April 2006 and March 2007, only five products were found to contain benzene at concentrations above 5 ug kg-1. The levels found were in a range from approximately 10–90 ug kg-1. A survey of 150 UK-produced soft drinks by the Food Standards Agency (FSA) published in 2006 showed that four products contained benzene at levels above 10 ug kg-1, and the highest level recorded was 28 ug kg-1. However, it has been reported that higher levels may develop in these products during prolonged storage, especially if they are exposed to daylight.
Benzene may also be formed in some mango and cranberry drinks in the absence of added preservatives, because these fruits contain natural benzoates.

History

Benzene was discovered in 1825 by Michael Faraday (1791–1867), who identified it in a liquid residue from heated whale oil. Faraday called the compound bicarburet of hydrogen, and its name was later changed to benzin by Eilhardt Mitscherlich (1794–1863), who isolated the compound from benzoin (C14H12O2).

Verwenden

Benzene occurs in coal and coal-tar distillationproducts and in petroleum products suchas gasoline. It is also found in the gases andleachates of landfills for industrial wastes,construction debris, and landscaping refuse(Oak Ridge National Laboratory 1989). Traceamounts of benzene, toluene, xylenes, andother volatile organics have been found inthe soils and groundwaters near many sanitarylandfills (U.S. EPA 1989a,b). Kramer(1989) has assessed the level of exposuresto benzene during removal, cleaning, pumping,and testing of underground gasoline storagetanks. The average human exposureswere 0.43–3.84 ppm (in 1.5–6 hours) and thehighest short-term (15–minute) exposure was9.14 ppm. Benzene also occurs in the tobaccosmoke (Hoffmann et al. 1989); thus the riskof its exposure may enhance from inhalingsuch smoke.
Benzene is used as a solvent for waxes,resins, and oils; as a paint remover; as a diluentfor lacquers; in the manufacture of dyes,pharmaceuticals, varnishes, and linoleum;and as a raw material to produce a numberof organic compounds.

Verwenden

Benzene is also converted to cyclohexane, which is used to produce nylon and synthetic fibers.

Verwenden

Manufacturing of ethylbenzene (for styrene monomer), dodecylbenzene (for detergents), cyclo- hexane (for nylon), phenol, nitrobenzene (for ani- line), maleic anhydride, chlorobenzene, diphenyl, benzene hexachloride, benzene-sulfonic acid, and as a solvent.

Verwenden

Benzene is also known as benzol, benzole, coal tar naphtha, and phenyl hydride, benzene is a clear, colorless, flammable liquid made by passing coke gas through oil, which is then distilled to produce benzene and toluol. The benzene is separated from the toluol by fractional distillation. Benzene is soluble in alcohol, ether, chloroform, and glacial acetic acid, but it is insoluble in water. Benzene was used as a solvent for many photographic operations in the 19th century. In the collodion process, benzene was used to dissolve rubber to both subcoat and supercoat negatives. It was also used as a solvent for Canada balsam in the Cutting method of sealing ambrotypes and cementing lens elements. Benzene was also used as a solvent for wax, gums, resins, and amber and in particular for retouching varnishes applied to silver bromide gelatin negatives.

Definition

A colorless liquid hydrocarbon with a characteristic odor. Benzene is a highly toxic compound and continued inhalation of the vapor is harmful. It was originally isolated from coal tar and for many years this was the principal source of the compound.Contemporary manufacture is from hexane; petroleum vapor is passed over platinum at 500°C and at 10 atmospheres pressure: C6H14 → C6H6 + 4H2 Benzene is the simplest aromatic hydrocarbon. It shows characteristic electrophilic substitution reactions, which are difficult to explain assuming a simple unsaturated structure (such as Kekulé’s (1865) or Dewar’s (1867) formulae). This anomolous behavior can now be explained by assuming that the six pi electrons are delocalized and that benzene is, therefore, a resonance hybrid. It consists of two Kekulé structures and three Dewar structures, the former contributing 80% and the latter 20% to the hybrid. Benzene is usually represented by either a Kekulé structure or a hexagon containing a circle (which denotes the delocalized electrons).

Definition

benzene: A colourless liquid hydrocarbon,C6H6; r.d. 0.88; m.p. 5.5°C;b.p. 80.1°C. It is now made fromgasoline from petroleum by catalyticreforming (formerly obtained fromcoal tar). Benzene is the archetypalaromatic compound. It has an un-saturated molecule, yet will not readilyundergo addition reactions. Onthe other hand, it does undergo substitutionreactions in which hydrogenatoms are replaced by otheratoms or groups. This behaviour occursbecause of delocalization of pelectronsover the benzene ring, andall the C–C bonds in benzene areequivalent and intermediate inlength between single and doublebonds. It can be regarded as a resonancehybrid of Kekulé and Dewarstructures. In formulaeit can be represented by a hexagonwith a ring inside it.

Definition

ChEBI: A six-carbon aromatic annulene in which each carbon atom donates one of its two 2p electrons into a delocalised pi system. A toxic, flammable liquid byproduct of coal distillation, it is used as an industrial solvent. Benzene is a carcinogen that also damages bone marrow and the central nervous system.

Vorbereitung Methode

Today benzene, which is a natural component of petroleum, is obtained from petroleum by several processes. Toluene hydrodealkylation involves mixing toluene (C6H5CH3) and hydrogen in the presence of catalysts and temperatures of approximately 500°C and pressures of about 50 atmospheres to produce benzene and methane: C6H5CH3 + H2 → C6H6 + CH4. Hydrodealkylation strips the methyl group from toluene to produce benzene. Toluene disproportionation involves combining toluene so that the methyl groups bond to one aromatic ring, producing benzene and xylene. Benzene can also be obtained from petroleum reforming in which temperature, pressure, and catalysts are used to convert petroleum components to benzene, which can then be extracted using solvents and distillation processes. Another source of benzene is pyrolysis gasoline or pygas.

Allgemeine Beschreibung

A clear colorless liquid with a petroleum-like odor. Flash point less than 0°F. Less dense than water and slightly soluble in water. Hence floats on water. Vapors are heavier than air.

Air & Water Reaktionen

Highly flammable. Slightly soluble in water.

Reaktivität anzeigen

Benzene reacts vigorously with allyl chloride or other alkyl halides even at minus 70°C in the presence of ethyl aluminum dichloride or ethyl aluminum sesquichloride. Explosions have been reported [NFPA 491M 1991]. Ignites in contact with powdered chromic anhydride [Mellor 11:235 1946-47]. Incompatible with oxidizing agents such as nitric acid. Mixtures with bromine trifluoride, bromine pentafluoride, iodine pentafluoride, iodine heptafluoride and other interhalogens can ignite upon heating [Bretherick 5th ed. 1995]. Benzene and cyanogen halides yield HCl as a byproduct (Hagedorn, F. H. Gelbke, and Federal Republic of Germany. 2002. Nitriles. In Ullman Encyclopedia of Industrial Chemistry. Wiley-VCH Verlag GmbH & Co. KGaA.). The reaction of Benzene and trichloroacetonitrile evolves toxic chloroform and HCl gasses. (Hagedorn, F., H.-P. Gelbke, and Federal Republic of Germany. 2002. Nitriles. In Ullman Encyclopedia of Industrial Chemistry. Wiley-VCH Verlag GmbH & Co. KGaA.).

Hazard

A confirmed carcinogen. Highly toxic. Flammable, dangerous fire risk. Explosive limits in air 1.5 to 8% by volume.

Health Hazard

Benzene is an acute as well as a chronictoxicant. The acute toxic effects from inhalation,ingestion, and skin contact are low tomoderate. The symptoms in humans are hallucination,distorted perception, euphoria, somnolence,nausea, vomiting, and headache. Thenarcotic effects in humans may occur frominhaling benzene in air at a concentrationof 200 ppm. High concentrations may cause convulsions. A 5- to 10-minute exposure to2% benzene in air may be fatal. Death mayresult from respiratory failure.
Benzene is an irritant to the eyes, nose,and respiratory tract. The chronic poisoningfrom benzene is much more severe than itsacute toxicity. The target organs to acuteand chronic poisoning are the blood, bonemarrow, central nervous system, respiratorysystem, eyes, and skin. Heavy occupationalexposures to benzene can cause bone marrowdepression and anemia, and in rare cases,leukemia. Leukemia may develop severalyears after the exposure ceases. Deaths fromleukemia, attributed to occupational exposureto benzene in the workplace, which may beon the order of 200 ppm concentration, havebeen documented (ACGIH 1986). Benzene islisted as a suspected human carcinogen. Inaddition to leukemia, malignant lymphoma,and myeloma, lung cancer in subjects exposedto benzene has been reported (Aksoy 1989).
Absorption of liquid benzene through theskin may be harmful. The main eliminationpathway for benzene absorbed throughinhalation or skin contact is metabolism.Hydroxyl radicals play an important role inthe process of metabolism. Khan and coworkers(1990) have reported the formationof formaldehyde and degradation of deoxyribose,suggesting the generation of hydroxylradicals during benzene toxicity to the bonemarrow S-9 fraction. The hydroxyl radicalsreact with benzene to form phenols and dihydroxyphenols,which are excreted rapidly inurine. About one-third of the retained benzeneis excreted as phenols in the urine. Theremaining two-thirds may be further degradedand attached onto the tissue or oxidized andexhaled as CO2.
Kalf and associates (1989) have investigatedthe action of prostaglandin H synthasein benzene toxicity and preventionof benzene-induced myelo- and genotoxicityby nonsteroidal anti-inflammatory drugs(NSAIDs). Indomethacin, a prostaglandin Hsynthase inhibitor prevented the dose- dependentbone marrow depression and increase in marrow prostaglandin E level in mice intravenouslydosed with benzene. Indomethacin,aspirin, or meclofenamate prevented thedecrease in cellularity and increase in micronucleatedpolychromatic erythrocytes in peripheralblood, caused by intravenous injectionof benzene (100–1000 mg/kg) in mice.

Health Hazard

Exposure to low concentrations of benzene vapor or liquid causes dizziness, lightheadedness, headache, loss of appetite, stomach upset, and irritation to the nose and throat. Prolonged exposure to high concentrations of benzene leads to functional irregularities in the heart beat and in severe cases to death. Benzene is a known carcinogen to humans. It causes leukemia and blood disorders such as aplastic anemia. The major types of leukemia related to benzene exposure are (i) acute myelogenous leukemia (AML); (ii) acute lymphocytic leukemia (ALL); (iii) chronic myelogenous leukemia, also called chronic myeloid leukemia (CML); (iv) chronic lymphocytic leukemia (CLL), and hairy cell leukemia (HCL). Occupational exposure to benzene is frequent, such as in road-tanker drivers and Chinese glueand shoe-making factory workers. Exposure to benzene has been linked with the development of rarer forms of leukemia, such as AML and ALL. It has also been linked to lymphoma and rare blood diseases

Health Hazard

The acute toxicity of benzene is low. Inhalation of benzene can cause dizziness, euphoria, giddiness, headache, nausea, drowsiness, and weakness. Benzene can cause moderate irritation to skin and severe irritation to eyes and mucous membranes. Benzene readily penetrates the skin to cause the same toxic effects as inhalation or ingestion. The chronic toxicity of benzene is significant. Exposure to benzene affects the blood and blood-forming organs such as the bone marrow, causing irreversible injury; blood disorders including anemia and leukemia may result. The symptoms of chronic benzene exposure may include fatigue, nervousness, irritability, blurred vision, and labored breathing. Benzene is regulated by OSHA as a carcinogen (Standard 1910.1028) and is listed in IARC Group 1 ("carcinogenic to humans"). This substance is classified as a "select carcinogen" under the criteria of the OSHA Laboratory Standard.

Health Hazard

Dizziness, excitation, pallor, followed by flushing, weakness, headache, breathlessness, chest constriction, nausea, and vomiting. Coma and possible death.

Brandgefahr

Behavior in Fire: Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back.

Brandgefahr

Benzene is a highly flammable liquid (NFPA rating = 3), and its vapors may travel a considerable distance to a source of ignition and "flash back." Vapor-air mixtures are explosive above the flash point. Carbon dioxide and dry chemical extinguishers should be used to fight benzene fires.

Flammability and Explosibility

Benzene is a highly flammable liquid (NFPA rating = 3), and its vapors may travel a considerable distance to a source of ignition and "flash back." Vapor-air mixtures are explosive above the flash point. Carbon dioxide and dry chemical extinguishers should be used to fight benzene fires.

Chemische Reaktivität

Reactivity with Water No reaction; Reactivity with Common Materials: No reactions; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.

Industrielle Verwendung

A colorless, liquid, inflammable, aromatichydrocarbon which boils at 80.1°C and freezesat 5.4 to 5.5°C. Benzene is used as a solventand particularly in Europe as a constituent ofmotor fuel. In the United States the largest usesof benzene are for the manufacture of styreneand phenol. Other important outlets are in theproduction of chlorinated benzenes (used inDDT and moth flakes), and benzene hexachloride,an insecticide.

Industrielle Verwendung

Benzene (C6H6, CAS No. 71-43-2) is an aromatic hydrocarbon compound used extensively in the chemical industry as an intermediate in the manufacture of polymers and other products. It is also a common atmospheric contaminant and is present in motor vehicle exhaust emissions and cigarette smoke.
In 1990, it was discovered by the USA soft drinks industry that benzene could be produced at low levels in certain soft drinks containing a benzoate preservative and ascorbic acid. Since benzene is a known human carcinogen, its presence in food and beverages is clearly undesirable.

Sicherheitsprofil

Confirmed human carcinogen producing myeloid leukemia, Hodgkin's dsease, and lymphomas by inhalation. Experimental carcinogenic, neoplastigenic, and tumorigenic data. A human poison by inhalation. An experimental poison by skin contact, intraperitoneal, intravenous, and possibly other routes. Moderately toxic by ingestion and subcutaneous routes. A severe eye and moderate sktn irritant. Human systemic effects by inhalation and ingestion: blood changes, increased body temperature. Experimental teratogenic and reproductive effects. Human mutation data reported. A narcotic. In industry, inhalation is the primary route of chronic benzene poisoning. Poisoning by skin contact has been reported. Recent (1 987) research indicates that effects are seen at less than 1 ppm. Exposures needed to be reduced to 0.1 ppm before no toxic effects were observed. Elimination is chiefly through the lungs. A common air contaminant. heat or flame. Explodes on contact with diborane, bromine pentafluoride, permanganic acid, peroxornonosulfuric acid, and peroxodisulfuric acid. Forms sensitive, explosive mixtures with iodine pentafluoride, silver perchlorate, nitryl perchlorate, nitric acid, liquid oxygen, ozone, and arsenic pentafluoride + potassium methoxide (explodes above 30℃). Ignites on contact with sodium peroxide + water, dioxygenyl tetrafluoroborate, iodine heptafluoride, and dioxygen difluoride. Vigorous or incandescent reaction with hydrogen + Raney nickel (above 210℃), uranium hexafluoride, and bromine trifluoride. Can react vigorously with oxidzing materials, such as Cla, Cr03,02, NClO4,03, perchlorates, (ACl3 + FClO4), (H2SO4 + permanganates), K2O2(, NH4OH + acetic acid), Na2O2. Moderate explosion hazard A dangerous fire hazard when when exposed to heat or flame. Use with adequate venulation. To fight fire, use foam, CO2, dry chemical. Poisoning occurs most commonly via inhalation of the vapor, although benzene can penetrate the skin and cause poisoning. Locally, benzene has a comparatively strong irritating effect, producing erythema and burning, and, in more severe cases, edema and even blistering. Exposure to high concentrations of the vapor (3000 ppm or higher) may result from failure of equipment or spillage. Such exposure, while rare in industry, may cause acute poisoning, characterized by the narcotic action of benzene on the central nervous system. The anesthetic action of benzene is sirmlar to that of other anesthetic gases, consisting of a preluninary stage of excitation followed by depression and, if exposure is continued, death through respiratory failure. The chronic, rather than the acute, form of benzene poisoning is important in industry. It is a recognized leukemogen. There is no specific blood picture occurring in cases of chronic benzol poisoning. The bone marrow may be hypoplastic, normal, or hyperplastic, the changes reflected in the peripheral blood. Anemia, leucopenia, macrocytosis, reticulocytosis, thrombocytopenia, hgh color index, and prolonged bleeding time may be present. Cases of myeloid leukemia have been reported. For the worker, repeated blood examinations are necessary, inclulng hemoglobin determinations, white and red cell counts, and dlfferential smears. Where a worker shows a progressive drop in either red or white cells, or where the white count remains below <5000/mm3 or the red count remains below 4.0 d o n / m m 3 , on two successive monthly examinations, the worker should be immediately removed from benzene exposure. Elimination is chefly through the lungs, when fresh air is breathed. The portion that is absorbed is oxidized, and the oxidation products are combined with sulfuric and glycuronic acids and eliminated in the urine. This may be used as a lagnostic sign. Benzene has a definite cumulative action, and exposure to a relatively hgh concentration is not serious from the point of view of causing damage to the blood-forming system, provided the exposure is not repeated. In acute poisoning, the wo

mögliche Exposition

Benzene is used as a constituent in motor fuels; as a solvent for fats; inks, oils, paints, plastics, and rubber, in the extraction of oils from seeds and nuts; in photogravure printing. It is also used as a chemical intermediate. By alkylation, chlorination, nitration, and sulfonation, chemicals, such as styrene, phenols, and malefic anhydride are produced. Benzene is also used in the manufacture of detergents, explosives, pharmaceuticals; in the manufacture of cyclohexane and ethylbenzene; and dye-stuffs. Increased concern for benzene as a significant environmental pollutant arises from public exposure to the presence of benzene in gasoline and the increased content in gasoline due to requirements for unleaded fuels for automobiles equipped with catalytic exhaust converters.

Carcinogenicity

Benzene is known to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in humans.

Environmental Fate

Biological. A mutant of Pseudomonas putida dihydroxylyzed benzene into cis-benzene glycol, accompanied by partial dehydrogenation, yielding catechol (Dagley, 1972). Bacterial dioxygenases can cleave catechol at the ortho and meta positions to yield cis,cis-muconic acid and α-hydroxymuconic semialdehyde, respectively (Chapman, 1972). Pure microbial cultures hydroxylated benzene to phenol and two unidentified phenols (Smith and Rosazza, 1974). Muconic acid was reported to be the biooxidation product of benzene by Nocardia corallina V-49 using hexadecane as the substrate (Keck et al., 1989).
Photolytic. A photooxidation rate constant of 6 x 10-11 cm3/molecule?sec at room temperature was reported for the vapor-phase reaction of benzene with OH radicals in air (Atkinson, 1985). The reported rate constant and half-life for the reaction of benzene and OH radicals in the atmosphere are 8.2 x 10-10 M/sec and 6.8 d, respectively (Mill, 1982). Major photooxidation products in air include nitrobenzene, nitrophenol, phenol, glyoxal, butanedial, formaldehyde, carbon dioxide, and carbon monoxide (Nojima et al., 1975; Finlayson-Pitts and Pitts, 1986).
Groundwater. Nielsen et al. (1996) studied the degradation of benzene in a shallow, glaciofluvial, unconfined sandy aquifer in Jutland, Denmark. As part of the in situ microcosm study, a cylinder that was open at the bottom and screened at the top was installed through a cased borehole approximately 5 m below grade. Five liters of water was aerated with atmospheric air to ensure aerobic conditions were maintained. Groundwater was analyzed weekly for approximately 3 months to determine benzene concentrations with time. The experimentally determined firstorder biodegradation rate constant and corresponding half-life following a 6-d lag phase were 0.5/d and 1.39 d, respectively.
Surface Water. Mackay and Wolkoff (1973) estimated an evaporation half-life of 37.3 min from a surface water body that is 25 °C and 1 m deep.
Chemical/Physical. Kanno et al. (1982) studied the aqueous reaction of benzene and other aromatic hydrocarbons (toluene, xylene, and naphthalene) with hypochlorous acid in the presence of ammonium ion. They reported that the aromatic ring was not chlorinated as expected (forming chlorobenzene) but was cleaved by chloramine forming cyanogen chloride (Kanno et al., 1982).

Lager

work with benzene 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. Benzene should be used only in areas free of ignition sources.

Versand/Shipping

UN1114 Benzene, Hazard Class: 3; Labels: 3— Flammable liquid

läuterung methode

For most purposes, *benzene can be purified sufficiently by shaking with conc H2SO4 until free from thiophene, then with H2O, dilute NaOH and water, followed by drying (with P2O5, sodium, LiAlH4, CaH2, 4X Linde molecular sieve, or CaSO4, or by passage through a column of silica gel, and for a preliminary drying, CaCl2 is suitable), and distillation. A further purification step to remove thiophene, acetic acid and propionic acid, is crystallisation by partial freezing. The usual contaminants in dry thiophene-free *benzene are non-benzenoid hydrocarbons such as cyclohexane, methylcyclohexane, and heptanes, together with naphthenic hydrocarbons and traces of toluene. Carbonyl-containing impurities can be removed by percolation through a Celite column impregnated with 2,4-dinitrophenylhydrazine, phosphoric acid and H2O. (Prepared by dissolving 0.5g DNPH in 6mL of 85% H3PO4 by grinding together, then adding and mixing 4mL of distilled H2O and 10g Celite.) [Schwartz & Parker Anal Chem 33 1396 1961.] *Benzene has been freed from thiophene by refluxing with 10% (w/v) of Raney nickel for 15minutes, after which the nickel is removed by filtration or centrifugation. Dry *benzene is obtained by doubly distilling high purity *benzene from a solution containing the blue ketyl formed by the reaction of sodium-potassium alloy with a small amount of benzophenone. Thiophene has been removed from *benzene (absence of bluish-green coloration when 3mL of *benzene is shaken with a solution of 10mg of isatin in 10mL of conc H2SO4) by refluxing the *benzene (1.25L) for several hours with 40g HgO (freshly precipitated) dissolved in 40mL glacial acetic acid and 300mL of water. The precipitate is filtered off, the aqueous phase is removed and the *benzene is washed twice with H2O, dried and distilled. Alternatively, *benzene dried with CaCl2 has been shaken vigorously for 0.5hour with anhydrous AlCl3 (12g/L) at 25-35o, then decanted, washed with 10% NaOH, and water, dried and distilled. The process is repeated, giving thiophene-free *benzene. [Holmes & Beeman Ind Eng Chem 26 172 1934.] After shaking successively for about an hour with conc H2SO4, distilled water (twice), 6M NaOH, and distilled water (twice), *benzene is distilled through a 3-ft glass column to remove most of the water. Absolute EtOH is added and the *benzene-alcohol azeotrope is distilled. (This low-boiling distillation leaves any non-azeotrope-forming impurities behind.) The middle fraction is shaken with distilled water to remove EtOH, and again redistilled. Final slow and very careful fractional distillation from sodium, then LiAlH4 under N2, removed traces of water and peroxides. [Peebles et al. J Am Chem Soc 82 2780 1960.] *Benzene liquid and vapour are very TOXIC and HIGHLY FLAMMABLE, and all operations should be carried out in an efficient fume cupboard and in the absence of naked flames in the vicinity. [Beilstein 5 H 175, 5 I 95, 5 II 119, 5 III 469.] Rapid purification: To dry benzene, alumina, CaH2 or 4A molecular sieves (3% w/v) may be used (dry for 6hours). Then benzene is distilled, discarding the first 5% of distillate, and stored over molecular sieves (3A, 4A) or Na wire.

Inkompatibilitäten

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides, many fluorides and perchlorates, nitric acid.

Waste disposal

Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber. All federal, state, and local environmental regulations must be observed. Dilution with alcohol or acetone to minimize smoke is recommended. Bacterial degradation is also possible.

Verordnung (Regulations)

Current USA and EU legislation does not set maximum limits for benzene in soft drinks. However, the FDA has adopted the Environmental Protection Agency (EPA) maximum contaminant level (MCL) for drinking water of 5 ppb as a quality standard for bottled water. ThisMCL has been used to evaluate the significance of benzene contamination in the soft drinks tested in surveys. The FSA has used the World Health Organization (WHO) guideline level for benzene in water of 10 mg kg-1 as a point of reference for its own survey results.

Benzol Upstream-Materialien And Downstream Produkte

Upstream-Materialien

Downstream Produkte


Benzol Anbieter Lieferant Produzent Hersteller Vertrieb Händler.

Global( 281)Lieferanten
Firmenname Telefon Fax E-Mail Land Produktkatalog Edge Rate
Shandong chuangyingchemical Co., Ltd.
13156170209
sale@chuangyingchem.com CHINA 4405 58
Henan Tianfu Chemical Co.,Ltd.
0371-55170693
0371-55170693 info@tianfuchem.com CHINA 20672 55
Mainchem Co., Ltd.
+86-0592-6210733
+86-0592-6210733 sale@mainchem.com CHINA 32447 55
ATK CHEMICAL COMPANY LIMITED
+86 21 5161 9050/ 5187 7795
+86 21 5161 9052/ 5187 7796 ivan@atkchemical.com CHINA 24191 60
career henan chemical co
+86-371-86658258
sales@coreychem.com CHINA 30001 58
NINGBO INNO PHARMCHEM CO., LTD.
13867897135
sales@nbinno.com CHINA 925 58
Hubei Jusheng Technology Co.,Ltd.
86-18871470254
027-59599243 sales@jushengtech.com CHINA 28236 58
Haihang Industry Co.,Ltd
86-531-88032799
+86 531 8582 1093 export@haihangchem.com CHINA 8918 58
QUALITY CONTROL CHEMICALS INC.
(323) 306-3136
(626) 453-0409 orders@qcchemical.com United States 8407 58
Hubei xin bonus chemical co. LTD
86-13657291602
027-59338440 sales@guangaobio.com CHINA 23049 58

71-43-2(Benzol)Verwandte Suche:


  • Benzene in dimethyl sulfoxide
  • Residual Solvent Class 1 - Benzene
  • Benzene [Sequencing Solvent]
  • Benzene for HPLC, >=99.9%
  • Benzene puriss. p.a., Reag. Ph. Eur., >=99.7%
  • Benzene ReagentPlus(R), thiophene free, >=99%
  • Benzene, HPLC, 99.5% min.
  • Benzene 〈H2O<30ppm〉
  • benzeen,benzen
  • Benzol Phenyl hydride Cyclohexatriene Coalnaphtha
  • AKOS BBS-00004227
  • BENZENE IN METHANOL NIST STANDARD
  • BENZENE ELECTRONIC GRADE
  • BENZENE 99+%
  • BENZENE HPLC GRADE
  • BenzeneGr
  • Hsr(HeavyNaptha9Benzene)
  • BenzeneForUvSpectroscopy
  • Benzene,Thiophene-FreeA.R.
  • BenzenePure(Crystallizable)
  • Benzene,ACS,99.0%min
  • BENZENE, REAG.
  • BENZENE-ISOBUTANOL SOLVENT, SOLUTION
  • BENZENE REAGENT (ACS)
  • benzene solution
  • benzene, anhydrous
  • benzene, spectrophotometric grade
  • BENZENE,OMNISOLV
  • BENZENE,PESTISOLV
  • BENZENE,PURIFIED
  • BENZENE,SPECTROSOLV
  • Benzene (I, T)
  • Benzene, HPLC Grade, 99.5%
  • Benzene, anhydrous, 99.8%, packaged under Argon in resealable ChemSealTM bottles
  • Benzene, Spectrophotometric Grade, 99.5+%
  • Benzene [Sequenation Solvent]
  • Benzene (1mg/ml in Methanol) [for Water Analysis]
  • Benzol Benzolene
  • Benzene, anhydrous, 99.8%, packaged under Argon in resealable ChemSeal bottles
  • 1,3,5-cyclohexatriene
  • cyclohexa-1,3,5-triene
  • Benzene, spectrophotometric grade,99+%
  • Benzene, ACS min
  • Benzene Standard
  • Benzene, synthesis grade
  • Benzene, anhydrous, 99,5%
  • Benzene, reagent grade, ACS, ISO
  • Benzene, dried (max. 0,01% H2O), reagent grade
  • Benzene, spectroscopy grade, Spectrosol
  • Benzene, anhydrous, with molecular sieves
  • Benzene 5g [71-43-2]
  • Benzene 1g [71-43-2]
  • Benzene/METHYLBENZENE
  • Benzene [for SpectrophotoMetry]
  • Benzene, anhydrous, 99.9%, Active Dry, packaged under Argon in resealable CheMSeal bottles
  • Benzene 99.8%
  • Benzene, Exceeds A.C.S. Specifications, HPLC Grade
  • N-alpha,Nim-Bis-Boc-D-histidine·
Copyright 2019 © ChemicalBook. All rights reserved