Abstract: A microwave furnace for heating materials has a microwave chamber with two microwave compartments made of microwave reflective material for retaining microwaves. One of the compartments is fixed and has an opening for discharging heated material. The other compartment is a rotating drum. The furnace also includes an elongated tubular member having a first and second open end. The tubular member is made of a microwave transparent material and is retained within the microwave chamber. A feeding mechanism feeds the material to be heated into the first end of the tubular member. The microwave furnace is provided with a mount for supporting the tubular member within the rotating microwave chamber by clasping the tubular member. The mount is adapted to rotate the tubular member along its axis and to position the tubular member such that the second end of the tubular member is substantially adjacent to the discharge opening of the fixed microwave chamber.