Gas/vapor-liquid phase separation can generally be achieved through mechanisms such as gravity, centrifugal forces, impingement and surface tension forces. In this study several micro-/ministructured devices for the separation of gas/vapor and liquid phases are investigated numerically and experimentally. By means of CFD the two-phase flow in the devices can be visualized and studied. The devices are compared with respect to pressure drop and separation efficiency. The enhancement of the specific exchange area and reduction of the characteristic length increase the phase separation. Although the rates of heat and mass transfer and therefore the efficiency of phase separation are proportional to the pressure gradient, devices achieving nearly 100% separation efficiency at moderate pressure drops can be developed by combining multiple separation mechanisms in microstructured devices. (C) 2013 Elsevier Ltd. All rights reserved.