Akademik Veri Yönetim Sistemi
FUEL, cilt.76, ss.1389-1394, 1997 (SCI-Expanded)
Pitches were prepared by three methods from Avgamasya asphaltite: (1) solvent extraction; (2) pyrolysis followed by vacuum distillation of the resulting tar; (3) air blowing of some of the vacuum-distilled tars. For Raman-Dincer heavy crude oil, only vacuum distillation was used. The chemical changes due to the different processes were studied by Fourier-transform infrared spectroscopy, softening point measurement and elemental analysis. Vacuum distillation and air blowing markedly increased the softening point, promoted dehydrogenation and aromatization through significant reduction of aliphatic structures and reduced the WC atomic ratio. The formation of oxygenated compounds is the major feature of the air blowing technique. The aromaticity and the softening point of solvent-extracted pitches depended on the effectiveness of the solvent. (C) 1997 Elsevier Science Ltd.