Micropetrographic characteristics of the Kosovo soft brown coal and their changes during catalytic hydroliquefaction

Marko Ercegovac; Bogdan Aleksić; Olga Cvetković; Branislav Marković; Bojana Aleksić; Hans Hagemann; Dragomir Vitorović

Marko Ercegovac University of Belgrade, Faculty of Mining and Geology, Institute of Regional Geology and Paleontology, Kamenička 6, 11000 Belgrade
Bogdan Aleksić IChTM, Center of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Beograd
Olga Cvetković IChTM, Center of Chemistry, Njegoševa 12, 11000 Beograd
Branislav Marković IChTM, Center of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Beograd
Bojana Aleksić IChTM, Center of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Beograd
Hans Hagemann Lehrstuhl fur Geologie, Geochemie und Lagerstatten des Erdols und der Kohle, Technische Hochshule Aechen, Lochnerstrasse 4-20, Aechen, deutshland.
Dragomir Vitorović IChTM, Center of Chemistry, Njegoševa 12, 11000 Beograd

Keywords: soft brown coal, liquefaction, petrography, solid residue, Kosovo Basin

Abstract

Bearing in mind the permanent interest for more rational utilization of coal energy, liquefaction by direct catalytic hydrogenation was investigated of the soft brovvn coal from Kosovo Basin, the largest deposit of this type of coal in Yugoslavia. The experiments were carried out at temperatures up to 440°C and pressures up to 15 MPa in the presence of a specific catalyst and solvent. The liquid products were fractionated by distillation into n-heptane soluble light oil (<70°C boiling point) and asphaltenes-oils insoluble in n-heptane. These products were characterized by gas chromatography and ultimate analysis. The gaseous products were analyzed by on-line gas chromatography. The changes in the maceral composition of the Kosovo coal during liquefaction were fbllowed by micropetrographic analysis of the solid residues. The high conversion degree in the liquefaction process obtained at choosen reaction conditions justified further investigations aimed at using this coal as raw material for producing high quality liquid fuels.