A description is given of a device (1) for sanitizing fluids comprising a fan (5) actuated by a motor and housed in a tubular conduit (10) in which fluid is propelled and a heat exchanger (7) in the form of a ceramic grid recuperator placed downstream of the fan (5), wherein the surfaces of the ceramic heat exchanger (7) impacted by the fluid are coated with photocatalytic material and associated with said exchanger (7) are a first lighting means (8) and a second lighting means (9) with LEDs, both of which are ultraviolet type A (UV-A), suitable for illuminating the surfaces coated with photocatalytic material.