Radio Frequency (RF) Plasma Treatment of Coal: Preliminary Results and Future Projections

Alongside the conventional combustion and pyrolysis processes, plasma pyrolysis and hydrogenation of coal for the purpose of generating liquid fuels and other chemicals are gaining popularity, while contributing towards sustainable clean energy and green environment. In the present study, plasma treatment of one subbituminous coal was carried out experimentally, to observe the interaction of coal with hydrogen plasma. The resulting products were detected and analysed using a high precision residual gas analyser. The preliminary mass spectrum clearly indicates the predominance of smaller C3 to C5 alkanes and a minor proportion of water vapour and oxygen, while showing the possibility of heteroatomic components having not interacted with or released during the plasma treatment. The hydrogen may have reacted with some of the lighter HC components generated during the primary reactions to produce secondary heavier HC compounds which are the higher mass units in the mass spectra. These heavier compounds possibly have a higher degree of aromaticity and might be saturated as well. The results of the present study have a far-reaching implication towards clean fuel technology. More obvious conclusions can be drawn to further investigate the behaviour of coal of different ranks and other carbonaceous materials during plasma treatment with the introduction of spectroscopic techniques.