Hydrocyclones are versatile equipments used in several industrial processes. Many modifications have been proposed to alter the typical structure of the hydrocyclone separator in order to improve its performance for specific process objectives; therefore, the filtering hydrocyclone fits into the category of non-conventional equipment. The only difference between a filtering hydrocyclone and the typical one is that the former has a porous conical wall, which produces a filtrate stream of pure liquid. In this work an optimized geometry for a filtering hydrocyclone with maximum total efficiency was obtained by using the Differential Evolution (DE) algorithm. The effects of the underflow diameter (Du) and the vortex finder length (l) on this new hydrocyclone were experimentally analyzed. The best values for Du and l were found so as to provide the highest total efficiency. (C) 2015 Elsevier B.V. All rights reserved.