Dehydration of isopropyl alcohol

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). 

In this Section, we consider examples of application of semiconductor sensors in investigation of heterogeneous catalytic reactions of dehydration of isopropyl alcohol and dissociation of hydrosine on zinc oxide. 

Figure 4.8. displays oscillograms of evolution of the electric conductivity of the ZnO film in the process of catalytic dehydration of isopropyl alcohol at various temperatures of the catalyzer and equal portions of alcohol (5-10-2 Torr) admitted into the reaction cell. Experimental curves 1-4 are bell-shaped. We suppose that this fact is associated with two circumstances. On one hand, alcohol vapors dissociate on the oxide film producing hydrogen atoms. The jump in electric conductivity is caused by chemisorption of these hydrogen atoms on the film which plays a part of the sensor in this case. Chi the other hand, the drop in electric conductivity is caused by complete dissociation of the admitted portion of alcohol ( depletion of the source of hydrogen atoms) and by... 

Eucken (88,89) and Wicke (90) have tried to explain the dehydrogenation and dehydration of isopropyl alcohol by an electron interchange between the alcohol and the zinc oxide alumina catalysts used for these conversions. We shall modify the mechanism proposed by Eucken and Wicke, following the theory of chemisorption. Contrary to these authors, we do not believe that the positions of the zinc and oxygen ions on the surface of the zinc oxide catalysts have any appreciable influence upon... 

Major markets as solvents and intermediates have made the ketones important commercial products lor many years. Acetone and mcthylethyl ketone have had the most impact on the chemical industry Acetone Is used s an intermediate In methyl isobutyl ketone, methyl methacrylate, diucelonc alcohol. ketone. hisphenol-A. phiwnc. and mesityl oxide Acetone is largely produced by dehydration of isopropyl alcohol In the production of phenol from cumene, acetone is produced as a by-product This mute to acetone has tended to control its price. 

The CdSA catalysts which contained varied amounts of cadmium ions were used for the dehydration of isopropyl alcohol into propylene and water at 200°, and the results obtained are shown in Fig. 21. A plot of the conversion of the dehydration reaction versus the amount of... 

A study has been made of the effect of alkali contamination on A1203-Si02 catalysts (variable Al20 Si02 ratio) in the dehydration of isopropyl alcohol and the cracking of cumene.428 The catalytic effect is markedly decreased by such contamination—the latter reaction being the more susceptible to this. 

The production of diisopropyl ether by the dehydration of isopropyl alcohol and the simultaneous removal of the product diisopropyl ether and water at the reaction zone was reported to increase the conversion of this equilibrium limited reaction. The dehydration of methanol to produce dimethyl ether was also reported. ... 

Later we demonstrated (1S7) the elevated catalytic activity with respect to dehydration of isopropyl alcohol and cracking of cumene of the solid tricalcium phosphate containing /3-radiators—radioactive isotopes of calcium and phosphorus. 

The relative efficiencies of different transient forms of alumina as catalysts for the dehydration of isopropyl alcohol have been measured. The specific activities were in the following sequence ... 

From the analysis of the literature available, oxides are more active in dehydrogenation reactions than dehydration. On extracting the numerical data (Krylov 1967), the catalytic reactivity (InK) has been calculated for different oxides in both dehydrogenation and dehydration of isopropyl alcohol under the same conditions and is listed in Table 9.3. 

Das P, Ray SK, Kuila SB, Samanta HS, Singha NR. 2011. Systematic choice of crosslinker and filler for pervaporation membrane—A case study with dehydration of isopropyl alcohol-water mixtures by polyvinyl alcohol membranes. Sep. Purif. Technol. 81 159-173. 

Turek, W., Haber, J., Krowiak, A. 2005. Dehydration of isopropyl alcohol used as an indicator of the type and strength of catalyst acid centres. Applied Surface Science 252 823-827. 

Arene complexes are utilized for the preparation of metallic layers which are deposited on various surfaces (See Table 2.31). They are also used for the preparation of highly pure metals. This is especially true for chromium group compounds. Pyrolytic decomposition of arene complexes found application for deposition of chromium on magnesium oxide in order to prepare the catalyst for dehydration of isopropyl alcohol. 

Catalytic activity has been used as a measure of acidity and acid strength. Recently, the activity for the dehydration of isopropyl alcohol or the isomerization of butene in the presence of an excess of air has been reported to be a good measure of acidity of some oxidation catalysts whose surface areas are so small that a gas adsorption method is difficult for the determination of acidity. In the case of the isomeriza-... 

As mentioned in 2.1.1.C, the catalytic activity for dehydration of isopropyl alcohol to propylene (rp) is proportional to the acidity of a catalyst. 

Fig. 2.13 Activity of F-AljOj and Na-AljOj for dehydration of isopropyl alcohol vs. Ho, mw...

The numbers of acid sites as determined by a titration method were 0.3, 0.2 and 2.0 m mol g for the silica gel modified by methods I, II, and III, respectively. The order of the catalytic activities of the three catalysts for both dehydration of isopropyl alcohol and the reaction of isobutene with methanol was in agreement with the order of the number of acid sites. 

Krylov [2] has shown the dependence of the activity and electronegativity on metal-metal atoms. Experiments have shown that for the dehydration of isopropyl alcohol, the activity decreases with increasing. electronegativity. This premise is consistent with the mechanism for the dehydration of alcohols, since the oxides have lower electronegativity. 

On the other hand, Krylov [2] claims that the activity of the dehydration of isopropyl alcohol is independent of the interatomic metal-monmetal distance,... 

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