In this study, the cost‐effective graphite powder (GPd)‐coated polyurethane (PGPd‐PU) sponge hollow tube (PGPd‐PUHT) was prepared for high‐efficient continuous oil removal, the hydrophobicity‐superoleophilicity PGPd‐PU sponge was fabricated through a simple dip‐coating method, which dipping PU sponge into GPd dispersion and drying, then coating polydimethylsiloxane (PDMS) on sponge skeleton, as‐prepared sponge could selectively absorb a variety of oils up to 34 times of its own weight for dimethyl sulfoxide (DMSO). The PGPd‐PUHT was prepared
Methods for the efficient and affordable remediation of oil spills and chemical leaks are crucially needed in today’s environment. In this study, we have developed a simple, magnetic, porous material based on polydimethylsiloxane (PDMS) and steel wool (SW) that can fulfill these needs. The PDMS-SW presented here is superhydrophobic, superoleophilic, and capable of absorbing and separating oils and organic solvents from water. The material is mechanically and chemically stable, even in salty environments, and can be magnetically guided. It exhibits good selectivity, recyclability, and sorption capacity, and can quickly and continuously absorb and remove large amounts of oils and organic solutions from stationary and turbulent water. In addition, PDMS-SW’s inherently high porosity enables direct, gravity-driven oil-water separation with permeate flux as high as ~32,000 L/m2·h and separation efficiency over 99%. The solution immersion process used to prepare the material is easily scalable and requires only a single step. Thus, with its demonstrated combination of affordability, efficiency, and ease of use, PDMS-SW has the potential to meet the demands of large-area oil and chemical clean-ups.
more » « less- NSF-PAR ID:
- 10154123
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Clean Water
- Volume:
- 2
- Issue:
- 1
- ISSN:
- 2059-7037
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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ABSTRACT via wrapping PGPd‐PU sponge on porous tubular support. The obtained PGPd‐PUHT could continuously collect various types of oils from water surface with flux as high as 1.52 kL/m2h, and excellent separation efficiency (up to 97.7%) for toluene, as well as remarkable reusability. Moreover, a continuous floating oil collection device based on PGPd‐PUHT was designed which showed excellent floating oil collection ability. In addition, our strategy possesses the advantages of low cost, simple preparation, highly efficient, and easily scale‐up, showing a great potential for dealing with practical oil spill remediation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020 ,137 , 48921. -
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