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Ethyl sulfuric acid

It is in the very nature of the catalytic process that the intermediate compound formed between catalyst and reactant is of extreme lability therefore not many cases are on record where the isolation by chemical means, or identification by physical methods, of intermediate compounds has been achieved concomitant with the evidence that these compounds are true intermediaries and not products of side reactions or artifacts. The formation of ethyl sulfuric acid in ether formation, catalyzed by HjSO , and of alkyl phosphates in olefin polymerization, catalyzed by liquid phosphoric acid, are examples of established intermediate compound formation in homogeneous catalysis. With regard to heterogeneous catalysis, where catalyst and reactant are not in the same... [Pg.65]

C2Hr,HS04 (aq.). Berthelot36 reported the heat of reaction of aqueous ethanol with aqueous sulfuric acid. His data yield, for aqueous ethyl-sulfuric acid, Qf=208.2, which value seems too low. [Pg.245]

Ethyl mercaptan, IV, 93, 94 Ethyl sulfuric acid, catalytic formation, V, 52... [Pg.345]

Reaction (1) is easily applicable to the preparation of the lower simple alkyl ethers which boil below the boiling point of the alcohol. For example, when ethyl alcohol is mixed with sulfuric acid in the cold, ethyl sulfuric acid is formed. When more alcohol is allowed to flow into such a mixture at 140-150°, ether, water, and some unchanged alcohol distill over. The mechanism of the reaction is assmned to involve, first the formation of ethyl sulfuric acid, and then the reaction of this with alcohol to form ether and regenerate the sulfuric acid. The regenerated acid combines with fresh alcohol and repeats the cycle until the water produced in the reaction by dilution diminishes its catalytic activity. Olefin formation takes place even at this temperature and decreases the yield. Further decrease in the yield results from the oxidizing action of sulfuric acid. [Pg.153]

Originally it was believed that etherification with sulfuric acid proceeded through the intermediate formation of alkyl sulfuric acids (R0S03H), since these products sometimes could be isolated from the reaction mixture. It now seems clear, however, that alkyl sulfuric acids are formed only as by-products in the reaction and are not actually intermediates in the etherification process. Thus, ethyl ter -butyl ether was prepared in yields of 95 per cent by heating a mixture of tert-butyl and ethyl alcohols containing 15 per cent sulfuric acid at 70°, yet titration of the cooled reaction mixture showed no evidence of the formation of an alkyl sulfuric acid.4 Furthermore, the yield of diethyl ether was 95 per cent when ethanol was passed through concentrated sulfuric acid heated to 140°, but when the reaction was carried out with ethyl sulfuric acid at the same temperature, much sulfur dioxide was evolved and the yield dropped to 70 per cent.4 8 We can, therefore, conclude that the... [Pg.214]

When exposed to air it oxidizes very slowly quite rapidly, however, in contact with platinum-black, forming valerianic acid. The same acid, along with other substances, is produced by the action of the more powerful oxidants upon amyl alcohol. Chlorin attacks it energetically, forming amyl chlorid, HCl, and other chlorinated derivatives. Sulfuric acid dissolves in amyl alcohol, with formation of amyl-sulfuric acid, S04(CtHu)H, corresponding to ethyl-sulfuric acid. It also forms similar acids with phosphoric, oxalic, citric, and tartaric acids. Its ethers, when dissolved in ethyl alcohol, have the taste and odor of various fruits, and are used in the preparation of artificial fruit-essences. Amyl alcohol is also used in analysis as a solvent, particularly for certain alkaloids, and in pharmacy for the artificial production of valerianic acid and the valerianates. [Pg.250]

Ethyl-sulfuric acid—(CaHs) f Oa—136—is formed as an inter-H )... [Pg.264]

In the presence of acetic anhydride or acetic acid, a similar compound of nitric and acetic acids, acetyl nitrate, is assumed [A. Pictet and P. Genequand, Ber. 36, 2526 (1902)], arid with benzoic acid, benzoyl nitrate [R. Willstatter, Ber. 4, 4152 (1909)]. Whether these compounds play the part assigned is similar to the question of whether ethyl sulfuric acid is always formed in the preparation of ether, and may be handled similarly. If it is formed at some stage of the reaction, it will probably be more able to form an addition compound, since it is obtained by loss of the elements of water from two other molecules and is probably more unsaturated. In this way, the velocity of the reaction might be accelerated, but an intermediate addition compound would still be formed. [Pg.114]

Equilibrium (1) represents the reaction between ethyl alcohol, sulfuric acid and water to form the intermediate product (2) the formation of the ethyl sulfuric acid (3) the formation of ethylene (4) the formation of ethylene and the simultaneous giving off of water (5) the formation of ethyl ether (6) the formation of a polymer of ethylene. All of these reactions have been observed experimentally, and the products actually obtained under given conditions, depend upon these conditions and the principles of the law of mass action. This list served to indicate the possibilities for the quantitative study of a common reaction presumably well-known. [Pg.144]

The formation of ethers may be considered from the same point of view as the formation of esters. This was indicated in connection with the reaction between ethylene and water, with sulfuric acid as catalyst, where the production of ether was shown in one of the equilibria. The reaction between alcohol and sulfuric acid to form ethyl sulfuric acid, and then, with more alcohol, ether, is also of historical interest. [Pg.155]

If the explanation of the relation between alcohols and ethers is accepted, it becomes easier to understand alkyl compounds and their reactions in general. They fall into the same class as the ammoniates and the hydrates, and may be called olefinates. Alcohol and ether are water olefinated to different degrees. Their constitutions may be expressed as follows (01 olefin) Alcohol, Ol.HOH ether, Oh.HOH alkyl iodide, Ol.HI ethyl sulfuric acid, En.H2S04 etc. The reaction for the formation of ethyl ether may be expressed as follows ... [Pg.159]

The maximum acid-combining capacity of keratin fibers, from reaction with simple acids such as hydrochloric, phosphoric, or ethyl sulfuric acid, is approximately 0.75mmol/g for unaltered human hair and about 0.82mmol/g for wool fiber [104]. This value approximates the number of dibasic amino acid residues in the fibers [105] (i.e., the combined amounts of arginine, lysine, and histidine) see Table 5-15.The primary sites for interaction with acid (protons) are probably the carboxylate groups of aspartic and glutamic acids (ionized by interaction with the dibasic amino acid residues) and the dibasic amino acid groups themselves. [Pg.246]

The surface of hair has both acidic and basic groups (i.e. amphoteric in nature). For unaltered human hair, the maximum acid combining capacity is approximately O.75mmol/g hydrochloric, phosphoric or ethyl sulfuric acid. This value corresponds to the number of dibasic amino acid residues, i.e. arginine, lysine or histidine. The maximum alkali combining capacity for unaltered hair is 0.44 mmol/g potassium hydroxide. This value corresponds to the number of acidic residues, i.e. aspartic and glutamic side chains. The isoelectric point (iep) of hair keratin (i.e. the pH at which... [Pg.91]


See other pages where Ethyl sulfuric acid is mentioned: [Pg.221]    [Pg.203]    [Pg.51]    [Pg.203]    [Pg.221]    [Pg.203]    [Pg.144]    [Pg.161]    [Pg.242]    [Pg.401]   
See also in sourсe #XX -- [ Pg.153 ]




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