In order to separate the impurities in vegetable seeds, a tribo-aero-electrostatic separator was designed and manufactured. Th e data analysis of the pure Descurainia Sophia seed shows that the interaction of the voltage, distance and angle was signifi cant on the weight of the D. Sophia at the level of 1%. To determine and compare the size of the separated seeds, a laser diff raction device with the possibility of analysing the size distribution of the particles was used. Th e results showed that the best purity (99.5%) with the highest percentage of the relative frequency of the D. Sophia seeds size was obtained for box 1 (the fi rst box) with a seed size of 680 μm. By moving from box 1 towards box 4, the amount of the impurities due to the variation of the electrical properties of the materials increases, although the value of the impurities for the samples is acceptable.
