Cyclohexane reaction apparatus

Reaction studies were performed in the apparatus shown in Figure 5. Both 0.5% Pd and 2.5% Pd catalysts were used in cyclohexane and A.C.S. grade hexane solvents. 

Gas reactions were carried out in a Parr kinetic apparatus at pressures of 250 and 90 lb/ in.2 at room temperature, in MeCN, with [TBPH] [complex] = 150 1 [complex] = 0.7 mM. In cyclohexane, [TBPH] [complex] [substrate] = 150 1 1100. Reaction time is 3 days. b Based on TBPH consumed. Percentage of starting material is in parentheses. c TN is turnover number oxidizing equivalents/mole of catalyst. d Two-day reaction. 

The dynamics of the reactions of 0( P) with cyclohexane, cyclohexene, and cyclohexa-1,4-diene have been studied by measurement of the product OH(X II) internal state distributions in a molecular beam/LIF apparatus. The rotational state distributions were found to be similar for all three reactions and consistent with small (1—3%) partitioning of the available energy, indicating that H-abstraction occurs only when the O atom is collinear with the C-H bond under attack. Comparisons with model predictions suggested that some of the extra energy available in the more exoergic reactions between 0( P) and the unsaturated hydrocarbons is released into internal excitation of the hydrocarbon radical product, resulting in only a modest increase in OH vibrational excitation. 

In this work, however, tests were desired to allow screening of hydrocaibon/catalyst combinations through measurenoenis of endotberm of reaction, extent of conversion, and identification of reaction products. However, the atmospheric-pressure bench scale test apparatus has been described elsewhere [11]. Parametric studies of the catalytic decomposition of n-heptane and cyclohexane were conducted to provide their stoichiometric analysis. The propo independent stoichiometric equations describing the catalytic decomposition of cyclohexane are ... 

A Fischer-Porter pressure bottle is charged with 100 mg (0.50 mmol) of trans-14 (X = Cl), 3 raL of propylene oxide, and 50 mL of dry cyclohexane, sealed, and carefully added to a constant temperature refluxing solvent bath (T ss 210 °C). Caution The thermolysis apparatus must be placed behind a safety shield. After 2.5 h, the pressure bottle is carefully removed, allowed to cool to r.t., vented, and the reaction mixture is concent rated. Purification of the residue by Hash chromatography (silica gel, hexane/EtOAc 40 1) gives cm-16 as a coloress oil yield 66 mg (81 %). 

Apparatus of a spray-pulsed reactor for rapid hydrogen evolution in the dehydrogenation reaction of cyclohexane and decalin as organic liquid carriers. 

For these measurements a differential reactor is used which satisfies the same design requirements as the one described above for the cyclohexane test, i.e., for the measurement of a rate constant under well-defined conditions of reactant concentration. The apparatus used has been previously described (5). Cumene, at atmospheric pressure, is passed over a sample of about 20 to 100 mg. of catalyst at a rate of about 2 X 10 moles/sec. at 420°. The catalyst is spread on a flat glass tray of 2 X 5-cm. dimensions (design requirements for products escape and diffusion are less severe than in the case of the cyclohexane test above, since reaction rates are encoim-tered in this reaction from about 0.1 to 10 jumoles/sec./g.) The rate of gas production is used to index the reaction rate and is measured by a mano-metric method (see ref. 2). 

The reaction mixture was passed through a Dry-Ice trap, from which samples were removed for analysis by refractive index. Catalytic activities are expressed as moles per cent cyclohexane per mole of benzene feed. The apparatus is shown diagrammatically in Fig. 25. Activities in mole per cent cyclohexane per mole of benzene feed are shown in... 

The HPLP apparatus has enabled the study of catalytic reactions over a pressure range covering many orders of magnitude. The reaction of cyclohexene with hydrogen has been studied between 10 and 10 Torr. The changes in rate and reaction probability over this wide pressure range are displayed in Fig. 5. It was found that at low pressure the principal product was benzene, and at high pressure the reaction predominantly formed cyclohexane. 

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