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The formation and growth rates of dispersed carbon particles were determined experimentally for pyrolysis of ethylene, benzene, and naphthalene in a reflected shock wave at temperatures of 1920-2560 K and hydrocarbon concentrations in argon of 1.8-20%. The diameter of the particles formed was estimated (30-600Å). The maximum rate of particle formation at various temperatures [(0.7-96) · 10 16 cm −3 · sec −1 ] and the particle growth rate (0.002-0.036 cm · sec −1 ) were determined from results of measurements of reaction (residence) times. For pyrolysis of benzene, the activation energy of the overall process of particle formation is 410 kJ/mole, and for all hydrocarbons studied, the activation energy of the overall process of particle growth is 5-50 kJ/mole. The surface average particle diameter increases with increasing concentration of the initial hydrocarbon at a constant temperature.

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The effect of thermal treatment at the temperature ranging from 800 to 2800°С on electrical resistance, specific adsorption surface and Raman spectrum of nanodispersed carbon black samples was investigated. It was determined that during the temperature increase, at first, the sample electrical resistance decreases (till the temperature of 1100 -1600°С), and then rises. Specific adsorption surface decreases to geometrical one with the increase of the treatment temperature. New band appears within the range of ~ 2570 cm -1 in Raman spectra after the thermal treatment at the temperature of 2000°С and higher.

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