An apparatus designed to form syn gas from carbonaceous materials such as coal includes a devolatilization reactor in combination with a reformer reactor which subsequently forms syn gas. The reformer reactor, in turn, is in communication with a particulate separator. The devolatilization reactor is fed with material using a compression feeder which drives air from the feed material, compresses it in a feed zone forming a seal between the feed hopper and the devolatilization reactor. The reformer reactor, as well as the particulate separators, are maintained in a heated furnace so that the temperature of the formed syn gas does not decrease below the reaction temperature until particulate material has been separated.