Y. Zhang et al., Characterization of mesocarbon microbeads and their derivatives by IR, SEMand Raman spectroscopy, SEKIYU GAKK, 42(4), 1999, pp. 192-200
Citations number
34
Categorie Soggetti
Geological Petroleum & Minig Engineering
Journal title
SEKIYU GAKKAISHI-JOURNAL OF THE JAPAN PETROLEUM INSTITUTE
Two kinds of mesocarbon microbeads (indicated MCMB-A and -B), prepared from
different coal tar pitch, as well as their derivatives obtained by butylat
ion and solvent extraction subjected to ultrasonic irradiation were investi
gated by infrared (IR) spectroscopy, scanning electron microscopy (SEM) and
Raman spectroscopy. Far IR spectroscopic analysis of these samples, MCMB-B
and its derivatives both showed electron transition absorptions at near-IR
region and aromaticities at C-H stretching region, stronger than those of
MCMB-A and its derivatives. SEM observation suggested that MCMB-B seemed to
be rich in free carbon, more than MCMB-A. These results indicated the diff
erence in structural characteristics between two MCMB samples: it could be
presumed that MCMB-B would have degree of condensation and graphitization h
igher than these of MCMB-A. This could account for the experimental results
previously reported that MCMB-B is inferior to MCMB-A regarding catalytic
reactivity in butylation and solvent extraction. SEM images also indicated
that MCMB had a surface layer of about 1-1.5 mu m. Raman spectra of the MCM
B, before and after solvent extraction, suggested that MCMB had a graphitiz
ed carbon layer on the surface, higher than the inner carbon.