The Malaysian Journal of Analytical Sciences Vol 12 No 1 (2008): 118 – 122

 

 

PYROLYSIS AND LIQUEFACTION OF ACETONE AND MIXED ACETONE/TETRALIN SWELLED MUKAH BALINGIAN MALAYSIAN SUB-BITUMINOUS COAL – THE EFFECT ON COAL CONVERSION

AND OIL YIELD

 

Mohd Fauzi Abdullah, Mohd Azlan Mohd Ishak and Khudzir Ismail

 

Fuel Combustion Research Laboratory,Faculty of Applied Sciences,

University Technology MARA, Arau Campus, 02600, Arau, Perlis

 

Abstract

The effect of swelling on Mukah Balingian (MB) Malaysian sub-bituminous coal macrostructure was observed by pyrolysing the swelled coal via thermogravimetry under nitrogen at ambient pressure.  The DTG curves of the pyrolysed swelled coal samples show the presence of evolution peaks at temperature ranging from 235 – 295 °C that are due to releasing of light molecular weight hydrocarbons.  These peaks, however, were not present in the untreated coal, indicating some changes in the coal macrostructure has occurred in the swelled coal samples. The global pyrolysis kinetics for coal that follows the first-order decomposition reaction was used to evaluate the activation energy of the pyrolysed untreated and swelled coal samples. The results thus far have shown that the activation energy for the acetone and mixed acetone/tetralin-swelled coal samples exhibit lower values than untreated coal, indicating less energy is required during the pyrolysis process due to the weakening of the coal-coal macromolecular interaction network. Moreover, liquefaction on the swelled coal samples that was carried out at temperatures ranging from 360 to 450 °C at 4 MPa of nitrogen pressure showed the enhancement of the coal conversion and oil yield at temperature of 420 °C, with retrogressive reaction started to dominate at higher temperature as indicated by decreased and increased in oil yield and high molecular weight pre-asphaltene, respectively. These observations suggest that the solvent swelling pre-treatment using acetone and mixed acetone/tetralin can improve the coal conversion and oil yields at less severe liquefaction condition.

 

Keywords: Swelling, liquefaction, pyrolysis, coal conversion, oil yield.

 

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