This work focusses on the thermal and chemical changes taking place on a low rank coal when it is subjected to hydropyrolysis conditions with Red Mud (RM) as the catalytic precursor. For each run, 5 g of coal were pyrolysed in a swept fixed bed reactor (SFB) at 40 kg/cm(2) hydrogen pressure. The variables of the process were: temperatures ranging from 400 to 600 degrees C; 0.5 and 2 l/min of hydrogen flow; 10 and 30 min residence time; and in the presence and absence of Red Mud. Conversion product distribution and a wide battery of complementary analyses allow information to be gathered regarding the changes undergone by the coal structure, both in its organic and inorganic components, in its conversion into liquids and chars. From the data obtained, it can be deduced that: (i) at 400 degrees C the iron catalyst is not active; (ii) at higher temperatures iron catalytic cracking is observed more than hydrogenating activity, due to the Fe2O3 transformation into (Fe3S4) crystallographically as spinel; (iii) in this coal hydropyrolysis one third of the coal is converted into liquids; and (iv) RM helps to reduce sulfur emissions by H2S fixation as Fe3S4.