Micro/nanoporous membrane based gas–water separation in microchannel

In this paper, a method coupling micro/nanoporous membranes with microchannels for the gas/water separation in microscale has been demonstrated. The principle of separation is based on the basic properties of membranes—wetted micro/nanoporous hydrophilic membranes can block gas due to a large water surface tension in the entrance of micro/nano pores to withstand the gas pressure, while it allows water to permeate with overcoming the flow resistance of pores; in contrast, hydrophobic membranes permit gas to penetrate but prevent water flow. These two kinds of membranes coupled with microchannels in cross-flow mode or dead-end mode can separate gas/water in microscale. The separation in cross-flow mode can achieve relative high water permeate flow rate, while the separation in dead-end mode can completely separate gas/water segments in a single operation step. The membrane-based separation method has low cost, easy integration into microfludics channels, design flexibility with two configuration modes (cross-flow and dead-end).