Abstract: A device for separating essentially immiscible fluids such as oil from rough water which utilizes a drum-shaped mechanism having generally vertically disposed oleophilic discs rotatable about a horizontal oil receiving trough, the unit being mounted in a frame also providing a sump which allows rotation of the drum, the complete unit being able to follow wave motion substantially independently of a supporting vessel through use of slide and guide mechanisms providing fore and aft restraint while allowing freedom of movement in heave and roll independent of ship motions. A major portion of the interior area of the drum about which the oleophilic discs rotate is filled with buoyancy material.