Ethylene, from ethyl alcohol

It has been employed instead of sulphuric acid in the hydrolysis of cellulose to give sugars. As a dehydrating agent in organic preparations, such as that of ethylene from ethyl alcohol, it is sometimes preferred to sulphuric acid. 

Therefore, in accordance with the facts, viz., (a) unsaturation and instability of ethylene, (b) The formation of ethylene from ethyl alcohol by loss of water, (c) The formation of ethylene from ethyl bromide, or iodide, by loss of hydrogen bromide, or iodide, (d) The identity of the di-brom addition product of ethylene ethylene bromide), with the symmetrical di-brom ethane and, (e) in accordance with our conceptions of carbon in its space relations and the geometric condition of such space arrangement, the structural formula for ethylene has been accepted as follows ... 

Example Ethylene from Ethyl Alcohol. Ethylene Bromide1... 

Adapted from H. V. Barrocas and A. I. Lacerda, Process for production of ethylene from ethyl alcohol, WO 2007/134415 A2, 2007. 

The chemical uses for ethylene prior to World War II were limited, for the most part, to ethylene glycol and ethyl alcohol. After the war, the demand for styrene and polyethylene took off, stimulating ethylene production and olefin plant construction. Todays list of chemical applications for ethylene reads like the WTiat s What of petrochemicals polyethylene, ethylbenzene (a precursor to styrene), ethylene dichloride, vinyl chloride, ethylene oxide, ethylene glycol, ethyl alcohol, vinyl acetate, alpha olefins, and linear alcohols are some of the more commercial derivatives of ethylene. The consumer products derived from these chemicals are found everywhere, from soap to construction materials to plastic products to synthetic motor oils. 

Sahcylsalicylic acid [532-94-3] (salsalate) is prepared by the action of phosphoms trichloride, phosphoms oxychloride, or thionyl chloride on salicylic acid at low temperatures in an appropriate solvent. The cmde product is recrystallized rapidly from ethyl alcohol to avoid hydrolysis and esterification. It is used as an analgesic and an antipyretic, as well as in the treatment of acute and chronic rheumatism and arthritis. It does not induce gastric disturbances because it is only slowly hydrolyzed in the intestine. Owing to the slowness of its hydrolysis (two molecules of salicylic acid per molecule of the ester), the action of sahcylsalicylic acid is less prompt but more persistent than that of other salicylates. Other salicylates of interest include ethylene glycol mono salicylate [87-28-5], dipropylene glycol monomethylether salicylate, bomyl salicylate [560-88-3], and -acetamidophenyl salicylate [118-57-0]. 

Ethylene is prepared from ethyl alcohol as in Prep. 9 or Prep. 436. The gas is passed first into an empty wash-bottle surrounded by a freezing mixture, and then through a second containing cone, sulphuric acid. The gas is next passed into antimony trichloride at 40°—50°, through... 

Dibromoethane is prepared from ethylene. The overall synthesis from ethyl alcohol is therefore formulated as shown ... 

A considerable wood hydrolysis industry with rather old traditions is located in the Soviet Union. The main fermentation product based on hexoses in wood hydrolyzates is ethyl alcohol, but pentoses and aliphatic acids can also be utilized in the production of proteins (see Section 10.2.3). A variety of chemicals, including ethylene, ethylene oxide, acetaldehyde, and acetic acid, can be produced from ethyl alcohol. One interesting future application of ethyl alcohol concerns its use as a motor fuel mixed with gasoline (gasohol). 

Material. Diethyl ether shall be made from ethyl alcohol conforming to the requirements for grade 1 or grade 2 of Specification MIL-A-463 (See in this Vol under Ethanol), or ether shall be made as a co-product in the manuf of Ethanol from ethylene... 

An analogous reaction to the above is the one commonly used for the preparation of ethylene. It consists in the removal of the elements of water from ethyl alcohol by heating with sulphuric acid or with zinc chloride ... 

This reaction does not ordinarily take place, but the analogous reactions, viz., the loss of the elements of water from ethyl alcohol, and the loss of hydrogen and iodine from ethyl iodide, do occur under the conditions previously stated. The formation of ethylene by these reactions may be represented as follows ... 

These syntheses are similar to those of ethylene from iodo ethane by the loss of hydrogen iodide and from ethyl alcohol by the loss of water. 

Ethylene was first produced from ethyl alcohol over heated alumina or silica [1]. Later, activated alumina and phosphoric acid on a support were commercially used [2], The fixed bed ethyl alcohol dehydration process was developed during world war I. In 1978, small plants were operative in India, Pakistan, Brazil and Peru. The viability of this process increased after the world wide oil crisis in 1973. A fluid-bed process was developed, which significantly reduced the plant installation and operative costs [3,4]. Further, an adiabatic reactor was designed by Barocas et al [5]. 

It was originally thought that some OH radicals must abstract hydrogen atoms from ethylene to form C2H3 radicals (14), but it is now concluded that all OH radicals add to ethylene (Reaction 1) and that the -hydroxy-ethyl radicals enter into reactions, not all of which give rise to acetaldehyde (13). Other recent evidence also supports this view (4). The absorption spectrum of the -hydroxyethyl radicals is similar to that of the a-hydroxyethyl radicals which can be prepared from ethyl alcohol (13). 

In the examples so far given, the application of the theory may be stated to be little more than an interesting hypothesis as to the disposition of atoms on a surface prior to and during reaction. It does not, for instance, enable it to be decided why a particular duplet should favor formation of acetaldehyde from ethyl alcohol, and another duplet, formation of ethylene. It would not appear that the intemuclear distances of the two types of duplet would be different, while the fact that both... 

Ethylene (Ethene) (bicarburetted hydrogen, ethene) n. A colorless, flammable gas derived by cracking petroleum and by distillation from natural gas. In addition to serving as the monomer for polyethylene, it has many uses in the plastics industry including the synthesis of ethylene oxide, ethyl alcohol, ethylene glycol (used in making alkyd and polyester resins), ethyl chloride, and other ethyl esters. Properties molecular weight, 28 bp, — 1.025°C Sp gr of liquid, 0.610/0°C. 

When dealing with esters of water-soluble, non steam-volatile, poly-hydric alcohols e.g., ethylene glycol or glycerol), the distillate consists of water only (density 1 00). The water soluble, non-volatile alcohol may be isolated by evaporation of the alkahne solution to a thick syrup on a water bath and extraction of the polyhydric alcohol from the salt with cold ethyl alcohol. 

Since 1960, the Hquid-phase oxidation of ethylene has been the process of choice for the manufacture of acetaldehyde. There is, however, stiU some commercial production by the partial oxidation of ethyl alcohol and hydration of acetylene. The economics of the various processes are strongly dependent on the prices of the feedstocks. Acetaldehyde is also formed as a coproduct in the high temperature oxidation of butane. A more recently developed rhodium catalyzed process produces acetaldehyde from synthesis gas as a coproduct with ethyl alcohol and acetic acid (83—94). 

Other by-products include acetone, carbonaceous material, and polymers of propylene. Minor contaminants arise from impurities in the feed. Ethylene and butylenes can form traces of ethyl alcohol and 2-butanol. Small amounts of / -propyl alcohol carried through into the refined isopropyl alcohol can originate from cyclopropane [75-19-4] in the propylene feed. Acetone, an oxidation product, also forms from thermal decomposition of the intermediate sulfate esters, eg. 

Direct Hydration. The acid-catalyzed direct hydration of propylene is exothermic and resembles the preparation of ethyl alcohol from ethylene (qv). 

Turmeric oleoresin is the combination of flavor and color principles obtained from turmeric by extracting it with one or a combination of the following solvents acetone, ethyl alcohol, ethylene dichloride, hexane, isopropyl alcohol, methyl alcohol, methylene chloride, and trichloroethylene. 

Medium Boiling Esters. Esterificatioa of ethyl and propyl alcohols, ethylene glycol, and glycerol with various acids, eg, chloro- or bromoacetic, or pymvic, by the use of a third component such as bensene, toluene, hexane, cyclohexane, or carbon tetrachloride to remove the water produced is quite common. Bensene has been used as a co-solvent ia the preparatioa of methyl pymvate from pymvic acid (101). The preparatioa of ethyl lactate is described as an example of the general procedure (102). A mixture of 1 mol 80% lactic acid and 2.3 mol 95% ethyl alcohol is added to a volume of benzene equal to half that of the alcohol (ca 43 mL), and the resulting mixture is refluxed for several hours. When distilled, the overhead condensate separates iato layers. The lower layer is extracted to recover the benzene and alcohol, and the water is discarded. The upper layer is returned to the column for reflux. After all the water is removed from the reaction mixture, the excess of alcohol and benzene is removed by distillation, and the ester is fractionated to isolate the pure ester. 

Industrial ethyl alcohol can be produced synthetically from ethylene [74-85-17, as a by-product of certain industrial operations, or by the fermentation of sugar, starch, or cellulose. The synthetic route suppHes most of the industrial market in the United States. The first synthesis of ethanol from ethylene occurred in 1828 in Michael Faraday s lab in Cambridge (40). 

There are two main processes for the synthesis of ethyl alcohol from ethylene. The eadiest to be developed (in 1930 by Union Carbide Corp.) was the indirect hydration process, variously called the strong sulfuric acid—ethylene process, the ethyl sulfate process, the esterification—hydrolysis process, or the sulfation—hydrolysis process. This process is stiU in use in Russia. The other synthesis process, designed to eliminate the use of sulfuric acid and which, since the early 1970s, has completely supplanted the old sulfuric acid process in the United States, is the direct hydration process. This process, the catalytic vapor-phase hydration of ethylene, is now practiced by only three U.S. companies Union Carbide Corp. (UCC), Quantum Chemical Corp., and Eastman Chemical Co. (a Division of Eastman Kodak Co.). UCC imports cmde industrial ethanol, CIE, from SADAF (the joint venture of SABIC and Pecten [Shell]) in Saudi Arabia, and refines it to industrial grade. 

Other synthetic methods have been investigated but have not become commercial. These include, for example, the hydration of ethylene in the presence of dilute acids (weak sulfuric acid process) the conversion of acetylene to acetaldehyde, followed by hydrogenation of the aldehyde to ethyl alcohol and the Fischer-Tropsch hydrocarbon synthesis. Synthetic fuels research has resulted in a whole new look at processes to make lower molecular weight alcohols from synthesis gas. 

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