Glycol, from ethylene chlorohydrin

Ethylene glycol was originally commercially produced in the United States from ethylene chlorohydrin [107-07-3J, which was manufactured from ethylene and hypochlorous acid (eq. 8) (see Chlorohydrins). Chlorohydrin can be converted direcdy to ethylene glycol by hydrolysis with a base, generally caustic or caustic/bicarbonate mix (eq. 9). An alternative production method is converting chlorohydrin to ethylene oxide (eq. 10) with subsequent hydrolysis (eq. 11). 

The same name would ordinarily be used even if the polymer were synthesized from ethylene glycol (HOCH2CH2OH), ethylene chlorohydrin (CICH2CH2OH), or bischloromethyl ether (CICH2OCH2CI). Similarly, structure 1-13 is called polycaprolactam because it is made industrially from the lactam by reaction (1-5), in preference to polymerization of the parent amino acid, H2N (CH2).[Pg.29]

The next major project for the Industrial Testing Laboratory was an attempt to improve the process of making ethylene glycol from ethylene via the hydrolysis of ethylene chlorohydrin. In his attempt to produce this "anti-freeze" by hydrolysis of ethylene dichloride with sodium polysulfide, "Doc" Patrick obtained a gummy gunk which he named "Thiokol" based on the greek word theion (sulfur) and kommi (gum). 

Ethylene oxide [75-21-8] was first prepared in 1859 by Wurt2 from 2-chloroethanol (ethylene chlorohydrin) and aqueous potassium hydroxide (1). He later attempted to produce ethylene oxide by direct oxidation but did not succeed (2). Many other researchers were also unsuccesshil (3—6). In 1931, Lefort achieved direct oxidation of ethylene to ethylene oxide using a silver catalyst (7,8). Although early manufacture of ethylene oxide was accompHshed by the chlorohydrin process, the direct oxidation process has been used almost exclusively since 1940. Today about 9.6 x 10 t of ethylene oxide are produced each year worldwide. The primary use for ethylene oxide is in the manufacture of derivatives such as ethylene glycol, surfactants, and ethanolamines. 

The petrochemical industry had its birth in the early 1900s. In 1913 propylene, a by-product of cracking, was introduced. In 1920 isopropyl alcohol was made from petroleum. In 1923 the first derivatives of ethylene were commercialized ethylene chlorohydrin, ethylene glycol, and dichloroethane. By the 1940s petrochemicals were fully developed in the... 

Chloroethyl benzoate has been prepared from benzoyl chloride and ethylene chlorohydrin from benzoic acid, ethylene glycol, and hydrogen chloride at 100° from ethylene oxide and benzoyl chloride from benzoyl chloride and dioxane in the presence of titanium tetrachloride from benzoic acid, ethylene, and chlorine in the presence of various catalysts. It has also been obtained by hydrolysis of 2-chloroethyl benzimidate " by the action of bromomagnesium benzoate on 2-chloroethyl -toluene-sulfonate and by the action of sodium benzoate on bis-(2-chloroethyl) sulfate. ... 

Propylene oxide is produced from the chlorohydrination of propene similar to the process used to make ethylene oxide (see Ethene). A major use of propylene oxide involves hydrating propylene oxide to produces propylene glycol, propylene polyglycols, and other polyether polyols. These products are used to produce both rigid and flexible polyurethane foams, but they are also used to produce polyurethane elastomers, sealants, and adhesives. 

Wyandotte A process for making a mixture of ethylene and propylene glycols from propane for use as antifreeze. The propane is cracked to a mixture of ethylene and propylene these are not separated but are converted to the corresponding glycols by chlorohydrination. Developed by the Wyandotte Chemicals Corporation. 

It may be ptepd by nitration of ethylene glycol, (CH2)2(OH)2with a mixed nitric-sulfuric acid in the same apparatus that is used for prepn of NG. The glycol is prepd by synthesis from ethylene and ethylene chlorohydrin (See also Refs 12 13)... 

Further evidence for heterolytic decomposition is obtained from the effect of olefin structure on product distribution. Table II shows the ratio of carbonyl to glycol product for three olefins. Listed for comparison is the carbonyl/glycol ratio for the chlorohydrin, which corresponds to the structure of the oxythallation adduct from ethylene and propylene. The effect of structure on the ratio is qualitatively the same for the thallic ion oxidation and the hydrolysis of the corresponding chlorohydrin. Since the product distributions for both are inconsistent with neighboring hydroxyl participation (Reaction 33) the carbonyl/glycol ratio is a measure of the competition between hydride shift vs. water attack in... 

As early as in 1904 the substance was proposed [35] as an additive to lower the freezing temperature of nitroglycerine, but its practical application on a large scale was hindered by lack of the raw material, propan-1,2-diol. It is only recently that the synthesis of ycol from ethylene led to the development of a method for producing methyl glycol from propylene via chlorohydrin. Even so, propylene-1,2-glycol is somewhat more expensive than glycols derived from ethylene. 

Ethylene Chlorohydrin. 2-Chtoroeihanol 2-chlo-roethy] alcohol glycol chlorohydrin. C,H,C10 mol wt 80.52. C 29.83%. H 6.26%. Cl 44.04%, O 19.87%. ClCHj-CHjOH. Made from ethylene by action of a hypochlorite. Toxicity data H. F. Smyth et al, 3. Ind. Hyg. Toxicol 23, 259 (1941). E. Browning, Toxicity and Metabolism of Industrial Solvents (Elsevier, New York, 1965) pp 397-401. Review G. H. Riesser in Kirk-Othmer Encyclopedia of Chemical Technology vol. 5 (Wiley-interscience, New York, 3rd ed.. 1979) pp 848-864. 

The hydrolysis of the amyl chlorides with sodium oleate and caustic soda solution to form the corresponding alcohols is the basis of a flourishing industry and is discussed on another page. The ease of removal of halogen increases markedly from chlorine to iodine and with increasing complexity of the compound. Ethylene chlorohydrin, for example, is easily and smoothly hydrolyzed to ethylene glycol by aqueous sodium bicarbonate CH,0HCH,C1 + NaHCO, aq. - CH,OHCH,OH -H CO. + NaCl... 

Ethylene chlorohydrin vapors form an explosive mixture with air the LEE and UEL values are 4.9% and 15.9% by volume of air, respectively. Among the hazardous reaction products are ethylene oxide, formed by internal displacement of the chlorine atom by the alkoxide ion, ethylene glycol formed by hydrolysis with sodium bicarbonate at 105°C (221°F), and ethylene cyanohydrin resulting from the reaction with alkali metal cyanides. 

A pilot reactor is used to determine the economic feasibility of ethylene glycol production from two available process streams containing 1.79mol/dm sodium bicarbonate and 3.73 mol/dm ethylene chlorohydrine in water. 

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