Ethyl ether hazards

Toxicology. The toxicity of ethyl ether is low and its greatest hazards in industry are fire and explosion. The vapor is absorbed almost instandy from the lungs and very prompdy from the intestinal tract. It undergoes no chemical change in the body. Prevention and control of health hazards associated with the handling of ethyl ether depend primarily on prevention of exposure to toxic atmospheric concentrations and scmpulous precautions to prevent explosion and fire. 

A concentration of 35,000 ppm in air produces unconsciousness in 30—40 minutes. This concentration also constitutes a serious fire and explosion hazard, and should not be permitted to exist under any circumstance. Any person exposed to ethyl ether vapor of any appreciable concentration should be prompdy removed from the area. Recovery from exposure to sublethal concentrations is rapid and generally complete. Except in emergencies, and then only with appropriate protective equipment, no one should enter an area containing ether vapor until the concentration has been found safe by measurement with a combustible-gas indicator. 

Isopropyl Ether. Isopropyl ether is manufactured by the dehydration of isopropyl alcohol with sulfuric acid. It is obtained in large quantities as a by-product in the manufacture of isopropyl alcohol from propylene by the sulfuric acid process, very similar to the production of ethyl ether from ethylene. Isopropyl ether is of moderate importance as an industrial solvent, since its boiling point Hes between that of ethyl ether and acetone. Isopropyl ether very readily forms hazardous peroxides and hydroperoxides, much more so than other ethers. However, this tendency can be controlled with commercial antioxidant additives. Therefore, it is also being promoted as another possible ether to be used in gasoline (33). 

The next simplest ether is the ether with the simplest alkane as one of the hydrocarbon backbones and the next alkane, which is methyl ethyl ether. Its molecular formula is CH3OC2H5. It is a colorless gas with the characteristic ether odor. It has a flash point of 31 °F, and an ignition temperature of only 374°F. This property, of course, makes it an extreme fire and explosion hazard. 

Group C. Atmospheres such as ethyl ether, ethylene, or gases or vapors of equivalent hazard. 

Avoid contact with air at elevated temperatures because of its low (unstated) ignition temperature. Bums moderately in the open, but may explode in a nearly closed vessel. Presence of mono- and di-chloroacetylenes as impurities increases the flammability hazard, which may be reduced by addition of 1% of ethyl ether. 

The heat generated is dissipated by reflux of the ether. The hazard of this reaction relates to the large energy release, the unpredictable nature of the reaction initiation, and the general problems of using ethyl ether. 

Group C Ethyl ether, ethylene or gases of equivalent hazard... 

HAZARDOUS DECOMPOSITION PRODUCTS T will hydrolyze to form HC1 and di-2-(2-hydroxy ethyl thio) ethyl ether. 

DOT MARKING Poisonous liquids, n.o.s. Bis-(2-(2-chloroethylthio)ethyl) ether UN 2810, Inhalation Hazard... 

Acid chlorides. The corresponding acid and hydrogen chloride are the most likely impurities. Usually these can be removed by efficient fractional distillation. Where acid chlorides are not readily hydrolysed (e.g. aryl sulphonyl chlorides) the compound can be freed from contaminants by dissolving in a suitable solvent such as alcohol-free chloroform, dry toluene or petroleum ether and shaking with dilute sodium bicarbonate solution. The organic phase is then washed with water, dried with sodium sulphate or magnesium sulphate, and distilled. This procedure is hazardous with readily hydrolysable acid chlorides such as acetyl chloride and benzoyl chloride. Solid acid chlorides are satisfactorily crystallised from toluene, toluene-petroleum ether, petroleum ethers, alcohol-free chloroform/toluene, and, occasionally, from dry ethyl ether. Hydroxylic or basic solvents should be strictly avoided. All operations should be carried out in a fume cupboard because of the irritant nature of these compounds. 

The rate at which a particular substance will vapourize (evaporate) when compared to the rate of a known substance such as ethyl ether. This term is especially useful for health and fire-hazard considerations. 

SAFETY PROFILE Liquid air can cause dssue damage due to low temperature. Personnel exposed to compressed air may develop caisson disease (the bends, the chokes) if decompression is too rapid. Moderate explosion hazard when containers under pressure are shocked or exposed to heat or flame. Flammable materials, e.g., ethyl ether, hydrocarbons, or charcoal, which have been in contact with liquid air may explode very easily. Ordinary oxidation is greatly accelerated in compressed air. Moderately dangerous disaster hazard can react vigorously with reducing materials. 

DOT CLASSIFICATION Forbidden SAFETY PROFILE A poison. Can explode spontaneously. The solid, liquid and vapor are shock-sensitive explosives. Concentrated solutions in organic solvents may explode. Moderate fire hazard in the form of vapor by chemical reaction. A powerful oxidant. Moderately explosive when exposed to heat. The liquid explodes on contact with arsenic, sodium, silver foil, or phosphorus. Incompatible with Sb, ethyl ether, Ag, metals. When heated to decomposition it... 

SAFETY PROFILE SUghtly toxic by inhalation. Very dangerous fire hazard when exposed to heat, flame, or oxidizers. Dangerous explosion hazard when exposed to flame, sparks, etc. Violent reaction with AIH3 and LLAIH2. Keep in closed container away from heat and open flame. To fight fire, stop flow of gas. When heated to decomposition it emits acrid smoke and irritating fumes. See also ETHERS and ETHYL ETHER. 

It is hard to overemphasize the hazards met in using ethyl ether, even when it is free of peroxides it is highly volatile, and the flammability of its vapors makes explosions and fires ever-present dangers unless proper precautions are observed. 

Properties Yellow powder odor like benzoqui-none. Mp 123-126C, sublimes at 100C. Slightly soluble in water soluble in ethanol, ethyl ether, chloroform, benzene, and acetic acid. Combustible. Hazard Irritant. 

Bis(2-chloroethyl) sulfide and bis(2-chloroettiyl-thio)ethyl ether [mustard, mustard agent, mustard gas, HT, mustard T] (Hazardous Waste Code P910),... 

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