Abstract: A gas-liquid contact apparatus includes a rotor having an outer wall parallel to the axis of rotation of the rotor, a permeable element mounted within the rotor for rotation therewith, inlets to supply liquid and gas to the rotor and outlets for conducting a gas and liquid respectively from the rotor. The permeable element is made of a plurality of strips of permeable material in layers superimposed progressively from the outer wall inwards towards the axis of rotation, the strips being in end-to-end abutment and the abutments being circumferentially staggered in adjacent layers.