A device for the thermal treatment of viscous material, in particular for the thermal separation of material components contained in viscous material, comprising a housing having a heatable housing jacket, which surrounds a treatment chamber and forms a rotationally symmetrical treatment surface extending in the axial direction, a material inlet, which is arranged in an inlet region of the housing, for introducing the material to be treated into the treatment chamber, a material outlet, which is arranged in an outlet region of the housing, for discharging the material out of the treatment chamber, and a drivable rotor, which is arranged in the treatment chamber and extends coaxially, for producing a material film on the treatment surface, wherein the rotor comprises a hollow shaft, arranged in a manner distributed over the circumference of which are spreading elements, the radially outer end of which is spaced apart from the treatment surface, wherein the hollow shaft surrounds a condensation space, in which a condenser is arranged, and has through openings, through which gaseous material components escaping from the material during the thermal treatment can enter the condensation space, and at least some of the spreading elements are configured as delivery elements, which impart a delivery component to the material in the direction from the material inlet to the material outlet, characterized in that, at least in a longitudinal section of the rotor, some of the spreading elements are configured as delivery elements and some as distributing elements, which project from the hollow shaft and which comprise teeth, the shearing edge of which encloses an angle of less than 45° relative to the axial direction, and the delivery elements comprise at least one delivery rib, the radial outer edge of which encloses an angle greater than 45° relative to the axial direction. a housing having a heatable housing jacket, which surrounds a treatment chamber and forms a rotationally symmetrical treatment surface extending in the axial direction, a material inlet, which is arranged in an inlet region of the housing, for introducing the material to be treated into the treatment chamber, a material outlet, which is arranged in an outlet region of the housing, for discharging the material out of the treatment chamber, and a drivable rotor, which is arranged in the treatment chamber and extends coaxially, for producing a material film on the treatment surface, wherein the rotor comprises a hollow shaft, arranged in a manner distributed over the circumference of which are spreading elements, the radially outer end of which is spaced apart from the treatment surface, wherein the hollow shaft surrounds a condensation space, in which a condenser is arranged, and has through openings, through which gaseous material components escaping from the material during the thermal treatment can enter the condensation space, and at least some of the spreading elements are configured as delivery elements, which impart a delivery component to the material in the direction from the material inlet to the material outlet, characterized in that, at least in a longitudinal section of the rotor, some of the spreading elements are configured as delivery elements and some as distributing elements, which project from the hollow shaft and which comprise teeth, the shearing edge of which encloses an angle of less than 45° relative to the axial direction, and the delivery elements comprise at least one delivery rib, the radial outer edge of which encloses an angle greater than 45° relative to the axial direction.