Chemistry and kinetics of chemical vapor deposition of pyrocarbon - II - Pyrocarbon deposition from ethylene, acetylene and 1,3-butadiene in the low temperature regime

Pyrocarbon deposition from ethylene, acetylene and 1,3-butadiene was studied with a vertical hot-wall reactor at ambient pressure and 1000 degrees C; initial partial pressures of the hydrocarbons and residence time were varied. Steady-state pyrocarbon deposition rates and corresponding compositions of the gas-phase were determined. Reaction models describing homogeneous gas-phase and heterogeneous pyrocarbon deposition reactions were derived and applied for simulation of pyrocarbon deposition rates and the inhibiting effect of hydrogen. This latter effect is ascribed to a blocking of active sites at the growing pyrocarbon surface. (C) 1998 Elsevier Science Ltd. All rights reserved.