ChemicalBook
Chinese Japanese Germany Korea

ketene

ketene
ketene structure
CAS No.
463-51-4
Chemical Name:
ketene
Synonyms
Keten;ethenone;carbometene;Ethen-1-one;Carbomethene;ketene ISO 9001:2015 REACH
CBNumber:
CB9934768
Molecular Formula:
C2H2O
Formula Weight:
42.04
MOL File:
463-51-4.mol

ketene Properties

Melting point:
-150°
Boiling point:
bp -56°
Density 
0.6600
refractive index 
1.3040 (estimate)
form 
Gas
Exposure limits
TLV-TWA 0.9 mg/m3 (0.5 ppm); STEL 3.0 mg/m3 (1.5 ppm) (ACGIH); IDLH 50 ppm (NIOSH).
EPA Substance Registry System
Ketene (463-51-4)
SAFETY
  • Risk and Safety Statements
RIDADR  1955
HazardClass  2.3

ketene Chemical Properties,Uses,Production

Chemical Properties

Colorless gas with a sharp penetrating odor;liquefies at -56°C (-68.8°F); solidifies at-151°C (-239.8°F); soluble in alcohol andacetone, decomposed by water.

Uses

Organic chemical syntheses; conversion of higher acids into their anhydrides; for acetylation in the manufacture of cellulose acetate and aspirin

Uses

For the conversion of higher acids into their anhydrides; for acetylation in the manufacture of cellulose acetate and aspirin.

Uses

Ketene is used as an acetylating agent inthe production of cellulose acetate, aspirin,acetic anhydride, and in various organicsyntheses.

Production Methods

Ketene may be prepared also by pyrolysis of acetic anhydride or phenyl acetate or diketene. Other sources are quite unsatisfactory from a standpoint of yield. Small quantities may be made conveniently by heating acetone in a “ketene lamp.” This is a glass apparatus containing a Nichrome filament, heated electrically to red heat. Larger amounts are made by passing acetone or acetic acid through a tube at 700 °C. A very brief contact time is required, so that much of the acetone is undecomposed and has to be condensed and recycled. Also, it is imperative that the reaction tube be of inert material such as porcelain, glass, quartz, copper or stainless steel. A copper tube, if used, should be protected from oxidation by an iron sheath. Inert packing may be used (glass, vanadium pentoxide, porcelain), but just as good yields are obtained with empty tubes. No catalyst is known which accelerates this decomposition at significantly lower temperatures.

Health Hazard

Ketene is a highly toxic gas. It causes severeirritation to the eyes, nose, throat, and skin.Exposure to 10–15 ppm for several minutescan injure the respiratory tract. It causespulmonary edema. A 30-minute exposure to23 ppm was lethal to mice and a 10-minuteexposure to 200 and 750 ppm caused deathto monkeys and cats.

Fire Hazard

Ketene in its gaseous state should be flammable and explosive in air. The pure compound, however, polymerizes readily and cannot be stored as a gas. Its flash point and LEL and UEL values are not reported. It can react violently with oxidizers and many organic compounds. Its small size and the olefinic unsaturation impart further reactivity to the molecule.

Purification Methods

Ketene is prepared by pyrolysis of acetic anhydride. Purify it by passing through a trap at -75o and collecting in a liquid-nitrogen-cooled trap. Ethylene is removed by evacuating the ethylene in an isopentane-liquid-nitrogen slush pack at -160o. Store it at room temperature in a suitable container in the dark or better at -80o, but do not store it under pressure as it may EXPLODE. It is a strong IRRITANT when inhaled and is as poisonous as phosgene. See diketene in “Heterocyclic Compounds”, Chapter 4. [Hurd Org Synth Coll Vol I 330 1941, Andreades & Carlson Org Synth Coll Vol V 679 1973.]

ketene Preparation Products And Raw materials

Raw materials

Preparation Products


ketene Suppliers

Global( 8)Suppliers
Supplier Tel Fax Email Country ProdList Advantage
Dideu Industries Group Limited
029-88380327
Service@dideu.com CHINA 30013 58
ChemStrong Scientific Co.,Ltd 15920483169 0755-66853366-
sales@chem-strong.com China 26487 56
Chizhou Kailong Import and Export Trade Co., Ltd. Please Email
- xg01_gj@163.com China 9550 50

View Lastest Price from ketene manufacturers

Image Release date Product Price Min. Order Purity Supply Ability Manufacturer
2020-01-01 ketene
463-51-4
US $0.10 / KG 1KG 99.0% 1000 tons Shaanxi Dideu Medichem Co. Ltd

463-51-4(ketene )Related Search:


Copyright 2017 © ChemicalBook. All rights reserved