Hydrocracking of Heavy Hydrocarbons in a Plasma Spouted-Bed Reactor: Role of Alkyl Aromatic Compounds in the Presence of a High Flow of Hydrogen Radicals
J. L. Leuenberger
Laboratoire de Génie des Precédés Plasmas, Université Paris VI , ENSCP, 11 rue P. & M. Curie, 75231 Paris Cedex 05, France
Laboratoire de Genie des Precedes Plasmas Universite P. et M. Curie, ENSCP 11 rue P. et M. Curie 75005 Paris France
The aim of this work is the petroleum residue reforming. For this purpose, a plasma spouted-bed reactor has been selected. In order to promote cracking reactions and to avoid coke formation, a high flow of hydrogen radicals, obtained from an inductively coupled argon-hydrogen plasma, is introduced into the reactor. The weak activation energy Ea of the n-C16H34 cracking in the presence of atomic hydrogen (96 kJ/mol) compared to classical cracking energy value (250 kJ/mol) confirms the catalytic role of adsorbed atomic hydrogen.
In the plasma spouted-bed reactor, the high flow of hydrogen radicals promotes the toluene Ø−C bond scission, leading to a methyl radicals enrichment. Thus, an increase of the methyl radical flux raises the cracking rate by a factor of two, by increasing the preexponential term of the kinetic constant. Both H° and CH3° radicals seem to control the conversion rate of hydrocarbons, the kinetics phenomena and the carbon black deposit through recombinaison reactions with macro-radicals which are responsible for deposits.