Chlorination ethane

Dichloroethane is also one of the iatermediate products of high temperature thermal chlorination of ethane or ethyl chloride. In ethane chlorination, the reaction proceeds through ethyl chloride as an iatermediate (12). 1,1-Dichloroethane itself is usually an iatermediate ia the productioa of viayl chloride and of 1,1,1-tfichloroethane by thermal chlorination or photochlofination (13). 

CH3-CH2CI CH2CI-CH2CI Cl2C = CHCI Chlorinated ethanes Chlorinated ethenes... 

A highly economical production of ethyl chloride combines radical ethane chlorination and ethylene hydrochlorination.185 186 Called the Shell integrated process, it uses the hydrogen chloride produced in the first reaction to carry out the second addition step ... 

Ethylchloride can also be produced by ethane chlorination. In this case the reaction is conducted at 450°C and the volume ratio of ethane and chlorine is 8 1. Ethane reacts with chlorine much easier than methane, which makes it possible to use even natural gas, which contains only 10% of ethane and 90% of methane. Under such conditions ethane is almost completely chlorinated, whereas the formation of chlorine derivatives of methane is virtually ruled out. 

Write equations and give conditions for the reaction of a ethane + chlorine... 

The preceding chapters dealt exclusively with the fuel gases acetylene and ethene. Other fuel gases, such as e.g. ammonia, chlorine ethane, chlorine methane. 

ETHANE, CHLORINATED SOLVENTS (TRACE) HEXANE, HEAVY ALCOHOLS (pH 1-12) ... 

The reaction between hydrogen and chlorine is probably also of this type and many organic free radical reactions (e.g. the decomposition of ethanal) proceed via chain mechanisms. 

CCls CHO. A colourless oily liquid with a pungent odour b.p. 98°C. Manut actured by the action of chlorine on ethanol it is also made by the chlorination of ethanal. When allowed to stand, it changes slowly to a white solid. Addition compounds are formed with water see chloral hydrate), ammonia, sodium hydrogen sulphite, alcohols, and some amines and amides. Oxidized by nitric acid to tri-chloroethanoic acid. Decomposed by alkalis to chloroform and a methanoate a convenient method of obtaining pure CHCI3. It is used for the manufacture of DDT. It is also used as a hypnotic. 

Like the chlorination of methane chlorination of ethane is carried out on an industrial scale as a high temperature gas phase reaction... 

Chlorination of ethane yields in addition to ethyl chloride a mixture of two isomeric dichlorides What are the structures of these two dichlorides ... 

Methane ethane and cyclobutane share the common feature that each one can give only a single monochloro derivative All the hydrogens of cyclobutane for example are equivalent and substitution of any one gives the same product as substitution of any other Chlorination of alkanes m which the hydrogens are not all equivalent is more com plicated m that a mixture of every possible monochloro derivative is formed as the chlo rmation of butane illustrates... 

Carbon dioxide Carbon monoxide Chlorine Ethane Ethylene Hydrogen ... 

Most chlorofluorocarbons are hydrolytically stable, CCI2F2 being considerably more stable than either CCl F or CHCI2F. Chlorofluoromethanes and ethanes disproportionate in the presence of aluminum chloride. For example, CCl F and CCI2F2 give CCIF and CCl CHCIF2 disproportionates to CHF and CHCl. The carbon—chlorine bond in most chlorofluorocarbons can be homolyticaHy cleaved under photolytic conditions (185—225 nm) to give chlorine radicals. This photochemical decomposition is the basis of the prediction that chlorofluorocarbons that reach the upper atmosphere deplete the earth s ozone shield. 

Tetrachloroethylene can be prepared direcdy from tetrachloroethane by a high temperature chlorination or, more simply, by passing acetylene and chlorine over a catalyst at 250—400°C or by controlled combustion of the mixture without a catalyst at 600—950°C (32). Oxychl orin a tion of ethylene and ethane has displaced most of this use of acetylene. 

Oxychlorination reactor feed purity can also contribute to by-product formation, although the problem usually is only with low levels of acetylene which are normally present in HCl from the EDC cracking process. Since any acetylene fed to the oxychlorination reactor will be converted to highly chlorinated C2 by-products, selective hydrogenation of this acetylene to ethylene and ethane is widely used as a preventive measure (78,98—102). 

If the production of vinyl chloride could be reduced to a single step, such as dkect chlorine substitution for hydrogen in ethylene or oxychlorination/cracking of ethylene to vinyl chloride, a major improvement over the traditional balanced process would be realized. The Hterature is filled with a variety of catalysts and processes for single-step manufacture of vinyl chloride (136—138). None has been commercialized because of the high temperatures, corrosive environments, and insufficient reaction selectivities so far encountered. Substitution of lower cost ethane or methane for ethylene in the manufacture of vinyl chloride has also been investigated. The Lummus-Transcat process (139), for instance, proposes a molten oxychlorination catalyst at 450—500°C to react ethane with chlorine to make vinyl chloride dkecfly. However, ethane conversion and selectivity to vinyl chloride are too low (30% and less than 40%, respectively) to make this process competitive. Numerous other catalysts and processes have been patented as weU, but none has been commercialized owing to problems with temperature, corrosion, and/or product selectivity (140—144). Because of the potential payback, however, this is a very active area of research. 

Methane, chlorine, and recycled chloromethanes are fed to a tubular reactor at a reactor temperature of 490—530°C to yield all four chlorinated methane derivatives (14). Similarly, chlorination of ethane produces ethyl chloride and higher chlorinated ethanes. The process is employed commercially to produce l,l,l-trichloroethane. l,l,l-Trichloroethane is also produced via chlorination of 1,1-dichloroethane with l,l,2-trichloroethane as a coproduct (15). Hexachlorocyclopentadiene is formed by a complex series of chlorination, cyclization, and dechlorination reactions. First, substitutive chlorination of pentanes is carried out by either photochemical or thermal methods to give a product with 6—7 atoms of chlorine per mole of pentane. The polychloropentane product mixed with excess chlorine is then passed through a porous bed of Fuller s earth or silica at 350—500°C to give hexachlorocyclopentadiene. Cyclopentadiene is another possible feedstock for the production of hexachlorocyclopentadiene. 

Three industrial processes have been used for the production of ethyl chloride hydrochlorination of ethylene, reaction of hydrochloric acid with ethanol, and chlorination of ethane. Hydrochlorination of ethylene is used to manufacture most of the ethyl chloride produced in the United States. Because of its prohibitive cost, the ethanol route to ethyl chloride has not been used commercially in the United States since about 1972. Thermal chlorination of ethane has the disadvantage of producing undesired by-products, and has not been used commercially since about 1975. 

Chlorination of Ethane. Ethane [74-84-0] maybe chlorinated thermally, catalyticaHy, photochemicaHy, or electrolyticaHy. Monochlorination is favored because ethyl chloride chlorinates at about one-fourth of the rate at which it is itself produced from ethane. 

Thermal chlorination of ethane is generally carried out at 250—500°C. At ca 400°C, a free-radical chain reaction takes place ... 

The chlorine and ethane are brought together in a fluid bed of finely divided, inert, solid heat-transfer medium, eg, sand, at 380—440°C the linear velocity of the gas is sufficient to maintain the finely divided solid in suspension within the reactor (26). 

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