A free-standing superhydrophobic film for highly efficient removal of water from turbine oil

Abstract

A free-standing superhydrophobic film is prepared by sequentially dip-coating a commercially available filter paper with nano SiO₂ suspension, epoxy emulsion, and octyltrimethoxysilane solution. A surface with micro- or nano-roughness is formed because SiO₂ nanoparticles are uniformly and firmly adhered on the backbone of the filter paper by the cured epoxy resin. Furthermore, the surface energy is significantly reduced because of introducing octytrimethoxysilane. Such a surface structure makes the prepared film a superhydrophobic material. Due to its free-standing nature, this superhydrophobic film can be used to remove water from turbine oil by filtration. The efficiency of water removal is high (up to 94.1%), and the filtration process is driven solely by gravity without extra energy consumption. Because of the facile fabrication process and the high efficiency of water removal, this free-standing superhydrophobic film may find application in power industry.

Key words： superhydrophobicity; nanoparticles; dip coating; epoxy emulsion; turbine oil

Acknowledgements

This work is supported by Yunnan power grid Co., Ltd.

References

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