Abstract: An apparatus and method for producing porous polymer particles is disclosed. The apparatus includes a rotating atomizer wheel (39) onto which a uniform thin layer of a polymer may be applied via a distributor (40), followed by the movement of the polymer to the periphery of the wheel due to centrifugal force and the subsequent release of free flying particles at the periphery of the wheel. The apparatus further includes a catch tray (14) to collect the porous polymer particles produced and an enclosure defining a partition between an interior environment and an exterior environment of the apparatus. The enclosure includes an aperture allowing a gaseous exchange between the interior and exterior environments.