화학공학소재연구정보센터
Fuel Processing Technology, Vol.48, No.1, 61-72, 1996
Supercritical toluene extraction of a reduced Turkish lignite
Elbistan-Afsin lignite, 64.2% C (daf), was reduced with lithium in THF in the presence of purified naphthalene as an electron transfer agent. The reduced lignite was then extracted with supercritical toluene. Even under comparatively mild conditions, 340 degrees C, relatively large yields of supercritical extract were obtained, almost all of which dissolved in benzene. The n-pentane-soluble and benzene-soluble fractions of the extract were eluted using column chromatography. Less than half of the originally soluble material could be eluted with n-pentane or benzene, the total methanol eluates amounting to 56.1% of the initial extract. The eluates were analysed by gas chromatography/mass spectrometry. The amount of phenol was 23.6% of the original benzene soluble fraction. It was concluded that bond cleavage had taken place during the reduction of the lignite. The naphthalene used as an electron transfer agent participated in side reactions.