Spectral moments of polycyclic aromatic hydrocarbons. Solution of a kinetic problem.
The relationship between the rate of supercritical fluid extraction of polycyclic aromatic hydrocarbons (PAHs) from coal-tar pitch and some topological invariants are examined. The aim is to explain the appearance of a minimum value on the activation energy/molar mass curve of the PAHs. Rate constants are approximated using spectral moment expansion. It is shown that the size of the PAHs determines more than 95% of the extraction rate. Activation energy for the extraction of the PAHs was found to increase with increasing molar mass. The appearance of a minimum value on the activation energy/molar mass curve is the consequence of experimental difficulties resulting from the tendency of lower members of the PAHs to sublime.
Marković
Svetlana
S
Department of Chemistry and Physics, Technikon Pretoria, P.O. Box 56208, Arcadia 0007, Republic of South Africa. Mark5898@yahoo.com
Marković
Zoran
Z
Engelbrecht
Johan P
JP
McCrindle
Robert I
RI