An apparatus for separating hydrophilic material from hydrophobic material, comprising: (a) a body having a first and second parallel walls defining an elongated cavity; (b) a water-absorbing material in the cavity along the first wall and having a surface essentially parallel to the second wall, thereby defining a channel between the surface and the second wall; (c) a first inlet having a first inlet end disposed in the channel, the first inlet being configured for injecting a mixture of hydrophilic and hydrophobic material; (d) a first outlet having a first outlet end disposed in the channel proximate the surface downstream of the first inlet end and configured for removing the hydrophilic material; and (e) a second outlet having a second outlet end disposed in the channel a distance from the surface downstream of the first inlet end and configured for removing the hydrophobic material.