Das cis‐Cyclotetradecen gibt bei der katalytischen Dehydrocyclisierung in der Gasphase an Palladium‐Kohle bei 400–500° als Hauptprodukt Phenanthren und als Nebenprodukt Anthracen. Die gleichen aromatischen Kohlenwasserstoffe entstehen unter denselben Reaktionsbedingungen an Aktivkohle, in Abwesenheit von Palladium.

Aromatic polycyclic hydrocarbons have been obtained by gas‐phase dehydrocyclisation of cycloparaffins with 9, 12, 13, 14, 15, 16, 17, and 18 ring‐members, using a 5% palladium‐charcoal catalyst at 400°.

The kinetics of ethane oxidation was studied a t 320,340,353 and 38OoC, mixture composition 2 C~H G + 1 02. and total pressure 609 torr. I t was found that a t 320°C CH20 and CH3CHO were branching agents. A series of experiments was conducted on 2C2Hfi + 0 2 oxidation in the presence of 0.7% 14C-labeled ethylene. The ethylene oxide was found to form only from C2H4, formaldehyde formed from C2H4 and C2Hs; and CH3CH0, CzHsOH, and CH30H formed only from ethane. The formation rates of C2H4, C2H40, and CH2O were calculated by the kinetic tracer method. At 320°C the fraction of oxygen-containing products formed from CzH4 was 16-18%, and a t 353 and 380°C it was 30-40%.

Mathematical modeling was used for the kinetics of gas-phase propane oxidation at 586,613, and 658 K and pressures 172 and 250 torr. The reaction mechanism involving branching by decay of the peracetyl peroxy radical, and oxygen-containing products formed on decay of the RO, radical is discussed. Fair agreement between calculated and experimental results on the kinetics and accumulation rates of reaction products was obtained.The kinetics of gas-phase propane oxidation was studied earlier [l-51. The composition of products, the basic kinetic regularities, the compound (CH,CHO) responsible for degenerate chain branching were found. A reaction mechanism was suggested.Experiments were conducted under static conditions in a reactionpretreated quartz reactor at 313, 340, and 385°C and 172 and 250 torr. Chromatographic analysis showed C3H6, CHzO, CH,OH, CH,CHO, C3H60, CO, COz, and HzO as the basic products, CzH4, CHI, CzHs, and CzH50H in smaller amounts, and traces of acetone. In the runs using the kinetic isotope method with addition of labeled propylene the products were analyzed for radioactivity.Mathematical modeling is known to be a fairly effective method for analysis of the chemical reaction mechanisms with a view to assess the extent of their reliability. This refers in particular to the slow oxidation of alkanes [6-73.The present article attempts generalization of the known experimental results for the kinetics of gas-phase propane oxidation by means of mathematical modeling. A seemingly most probable mechanism [2] is proposed, and its steps are analyzed.The choice of the reaction mechanism of gas-phase propane oxidation involved two stages. The first consisted of selecting the basic steps

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