Direct recovery of spilled oil using hierarchically porous oil scoop with capillary-induced anti-oil-fouling

Tae-Jun Ko; Seohyun Cho; Seong Jin Kim; Young A Lee; Do Hyun Kim; Wonjin Jo; Ho-Young Kim; Shu Yang; Kyu Hwan Oh; Myoung-Woon Moon

doi:10.1016/j.jhazmat.2020.124549

Direct recovery of spilled oil using hierarchically porous oil scoop with capillary-induced anti-oil-fouling

J Hazard Mater. 2021 May 15:410:124549. doi: 10.1016/j.jhazmat.2020.124549. Epub 2020 Nov 18.

Authors

Tae-Jun Ko¹, Seohyun Cho², Seong Jin Kim², Young A Lee², Do Hyun Kim², Wonjin Jo², Ho-Young Kim³, Shu Yang⁴, Kyu Hwan Oh⁵, Myoung-Woon Moon⁶

Affiliations

¹ Materials and Life Science Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
² Materials and Life Science Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea.
³ Department of Mechanical Engineering and IAMD, Seoul National University, Seoul 08826, Republic of Korea.
⁴ Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
⁵ Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
⁶ Materials and Life Science Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea. Electronic address: mwmoon@kist.re.kr.

PMID: 33250313
DOI: 10.1016/j.jhazmat.2020.124549

Abstract

The pitcher plant has evolved its hierarchically grooved peristome to enhance a water-based slippery system for capturing insects with oil-covered footpads. Based on this, we proposed a hierarchically porous oil scoop (HPOS) with capillary-induced oil peel-off ability for repeatable spilled oil recovery. As the HPOS scoops oil-water mixture, water passes through the hole while the oil is confined within a curved geometry. The filter in HPOS has three levels of porous structures; (1) 3D-printed mesh structure with sub-millimeter scale hole to filter out oil from an oil-water mixture, (2) internal micropore in fibers enhancing capillarity and water transport, (3) O₂ plasma-induced high-aspect-ratio nanopillar structures imposing anti-oil-fouling property with capillary-induced oil peeling. As the oil-contaminated HPOS makes contact with water, water meniscus rises and peels off the oil immediately at the air-water interface. The oil-peel-off ability of the HPOS would prevent pores from clogging by oils for reuse. The study demonstrated that the HPOS recovers highly viscous oil (up to 5000 mm²·s^-1) with a high recovery rate (>95%), leaving the filtered water with low oil content (<10 ppm), which satisfies the discharge criterion of 15 ppm.

Keywords: Anti-oil-fouling; Direct oil recovery; Hierarchical structure; Oil scoop; Oil–water separation.

Publication types

Research Support, Non-U.S. Gov't