Reaction of tetrafluorohydrazine with oximes

Conclusions Reaction of tetrafluorohydrazine with dimethylglyoxime, acetaldoxime, and p-nitrosophenol gave the corresponding N-fluoroazoxy derivatives. Some special features of the process were investigated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 719–720, March, 1970.     

Reaction of tetrafluorohydrazine with unsaturated nitro compounds

Conclusions Addition of tetrafluorohydrazine to nitroalkenes can be realized in the presence of acetonitrile. The reaction becomes difficult when the dinitro- or dinitrofluoromethyl groups are near the double bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 717–718, March, 1970.     

Reaction of tetrafluorohydrazine with 1,1′,2,3,4,4′-hexafluorobutadiene and hexafluorocyclobutene

Russian Chemical Bulletin -     

Mass-spectrometric study of tetrafluorohydrazine and the products resulting from its breakdown under electron impact

Conclusions Electron-impact methods have been used to study positive (NF⁺, NF₂ ⁺, N₂F₂ ⁺) and negative (F^–, F₂ ^–, N₂F^–, NF₂ ^–) ion formation in the mass spectra of tetrafluorohydrazine and its decomposition products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1306–1311, June, 1978.The authors would like to thank V. Ya. Rosolovskii for a discussion of the results obtained in this work.     

Pyrolysis of azidopyrazines

2,3-Dichloro- and 2,5-dichloropyrazines were treated with sodium azide. The former gave diazidopyrazines and the latter, monoazidomonochloropyrazines. Pyrolysis of 2,3-diazidopyrazines resulted the production of 1,2-dicyanoiminoethanes and that of 2-azido-5-chloropyrazines, chloroimidazoles.     

Pyrolysis of fluorodiazirines

The thermal decomposition of difluorodiazirine and difluoraminofluorodiazirine results in the formation of difluorocarbene and difluoraminofluorocarbene, respectively. The isolable products of the pyrolyses include fluoro-alkenes, -cyclopropanes, -azines, -aziridines and in some cases isomerization products thereof.     

Pyrolysis of polyaromatic heterocyclics

The oxidative and thermal degradation of some polyaromatic heterocyclics in air and helium has been studied by dynamic thermogravimetry to 1400°C. Decomposition characteristics are the result of polymer structure, molecular weight, and method of preparation. Decomposition in air follows first-order rate laws, while degradation under inert conditions does not appear to follow simple rate laws. The activation energies for the decomposition in air are between 30 and 35 kcal./mole for most polymers investigated. Carbonaceous polymer residues at 1400°C. are present in varying quantities.     

环己烷的热裂解机理

用Gaussian 98程序包中AM1法和DFT方法,对液相沉积法制碳/碳（C/C）复合材料的碳源化合物环己烷的热解机理做了量子化学理论研究.通过对化合物6种可能的热裂解路径的热力学和动力学计算,找到了环己烷热裂解的主反应路径.结果表明：(1) AM1与DFT计算均显示,断裂C－C键,最终生成乙烯和2 丁烯的反应通道是环己烷的主要裂解通道,与质谱数据吻合; (2) 除主反应路径外,余下的由易到难生成化合物的顺序为甲基环戊烷 >环己烯 >4 甲基环戊烯 >1,3 丁二烯; (3) AM1方法可以很好地推测较大分子体系的热裂解机理,而DFT方法计算的热力学量更接近实验数据.     

Pyrolysis of 1,2-dichloropropane

The thermal decomposition of 1,2-dichloropropane at atmospheric pressure has been studied in the temperature range 227–590°C, in a flow system. Above 450°C, the reaction is homogenous and unimolecular with a rate constant: Below 450°C, a low activation energy, probably heterogenous process competes with the gas phase reaction The primary reaction products are HCl and the monochloropropene isomers; the relative amounts of each isomer depend on the temperature in the low but not in the high temperature region. The direction of the HCl elimination is discussed in terms of substituent effects at the α- and β-carbon positions and compared with literature data on similar reactions Secondary products are formed principally by further pyrolysis of allyl chloride. The first-order rate constant of this reaction is given by: .     

Pyrolysis of petroleum fractions

Dynamic kinetic analyses were performed on different Brazilian petroleum fractions by thermogravimetry. The data were treated by a multiple heating rate methodology. The apparent activation energies for the light and middle fractions within the range of 62–74 kJ mol⁻¹ and for heavy distillation residues were within the range of 80–100 kJ mol⁻¹ at lower conversions and 100–240 kJ mol⁻¹ at higher conversions. The kinetic study can be a criterion for tells apart the main phenomena involved in the thermal behavior of the refinery feedstock.     

Catalytic Pyrolysis of Methane

Methane decomposition over metal oxides/SiO₂ surface was investigated. At 1400 K obtained product distribution of this decomposition varied with metal oxide used. The effectiveness of these catalysts has been discussed in terms of activity and C₂ selectivity. ThO₂/SiO₂ was found to be the most effective catalyst for the catalytic decomposition of methane. Positive catalytic effect of ThO₂/SiO₂ on the pyrolysis has also been confirmed at 1073 K. At low reaction conversions, ethane and ethylene are found as major products. Yields of ethylene and other unsaturated products are sensitively inhibited by NO impurities in the methane. A reaction mechanism has been proposed to account observed experimental results.     

Pyrolysis kinetics of polypropylene

The pyrolysis of oil shale and plastic wastes is being presently considered as an alternative means of partial substitution of fossil fuels to generate the necessary energy to supply the increasing energy demand and as well as new technology to reduce the negative environment of plastic wastes. However, Knowledge of pyrolysis kinetics is of great imponrtance for the design and simulation of the reactor and in order to establish the optimum process conditions. In this study, the thermal decomposition of polypropylene, oil shale and their mixture was studied by TG under a nitrogen atmosphere. Experiments were carried out for various heating rates (2, 10, 20, 50 K min⁻¹) in the temperature range 300–1273 K. The values of the obtained activation energies are 207 kJ mol⁻¹ for polyethylene, 57 kJ mol⁻¹ for the organic matter contained in the oil shale and 174 kJ mol⁻¹ for the mixture. The results indicate that the decomposition of these materials depends on the heating rate, and that polypropylene acts as catalyst in the degradation of the oil shale in the mixture.     

Pyrolysis of 1,7-octadiene

Pyrolysis of 1,7-octadiene identified as an intermediate during the thermal degradation of cis-decalin, has been studied between 843 and 953 K. The 1,7-octadiene radical first produced, leads to the formation of α,α-olefinic fragments and to 1-ethyl-1,4-cyclohexadiene. by an internal cyclization. These are the precursors of the aromatic hydrocarbons resulting from the high-temperature pyrolysis of cis-decalin. The activation energy of the cracking of 1,7-octadiene has been calculated to be 180 kJ mole^?1 (43 kcal mole^?1)