Abstract: The invention relates to a particle separator and methods for separating the particles of a mixture. The apparatus of the invention employs two field elements to create a field in the space between the field elements. The surface contact of the particles of the mixture, inputted into the space between the field elements, triboelectrically charges the particles. Under the influence of the field, the charged particles substantially aggregate on one of two counter-rotating agitators, disposed operably in the space between the field elements, according to their respective polarities. The rotation of the agitators brings the charged particles into a substantially field-free space in the vicinity of the output ports. Some of the charged particles leave the agitators under the influence of external forces to enter one of the output ports based on their charge polarities.