In this study, an investigation was carried out into the thermal behaviours of peat, reed, lignite, bituminous coal and blends of these with peat. The blends were prepared in 20:80, 40:60, 60:40, 80:20. The samples were pyrolysed in a TG analyzer in a nitrogen atmosphere (50 mL/min) at temperatures ranging from 25 to 900 degrees C. Using TG/DTG graphs, variations were investigated, which occurred in reaction intervals, percent of weight loss, peak temperatures and maximum devolatilization rate. The activation energy (E) and pre-exponential constant (A) were calculated using the Arrhenius type kinetic model. (C) 2007 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.