One-step synthesis of a steel-polymer wool for oil-water separation and absorption

Abstract

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/m 2 •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.

A flexible biomimetic superhydrophobic and superoleophilic 3D macroporous polymer-based robust network for the efficient separation of oil-contaminated water

“…It is crucial to note that the absorption capacity might predominantly depend on the density of the various oils and the organic solvents. 23 The developed 3D macroporous superhydrophobic network of ODTCS-SiO 2 -PP-PU displayed an absorption capacity in the range of 18 to 34 times better than that of the previously reported recent materials, including aerogel composites (2-16 times), 24 PDMS-SW (12-27 times), 25 magnetic silicone sponges (7-17 times), 26 PDMS sponges (4-11 times), 23 and nitrogen-rich carbon aerogels (6-11 times). 27 Moreover, toluene absorption was specically compared with the previous literature and demonstrated better efficiency here than in the previously reported work ( Table 1).…”

Superhydrophobic and Conductive Foams with Antifouling and Oil–Water Separation Properties

“…The results have demonstrated that the separation efficiency of the PDMS-GR-Cu foam was very high, exceeding 99% for the tested oils and organic solvents with high flux rates (6216–11 700 L m –2 h –1 ) that are comparable or higher compared to the other fabricated filters (Figure b and Table S3). Although other oil–water separators exhibit superior separation performance, − they do not provide any mechanism to kill adherent bacteria, which may lead to the loss of their permeate flux, limiting their use in bacteria-contaminated environments . The foams were further examined for reusability and separation efficiency by taking chloroform as a model pollutant since both are characteristics necessary for practical application.…”

Liquid-Infused Membranes with Oil-in-Water Emulsions

“…Gravity-driven oil–water separation results showed permeate flux as high as ∼32 000 L/m 2 h with separation efficiency over 99%. 31…”

“…Gravity-driven oil−water separation results showed permeate flux as high as ∼32 000 L/m 2 h with separation efficiency over 99%. 31 Limited strength, durability, and unsatisfactory performance are the main drawbacks of membranes with superwetting/ antiwetting properties. 21 Multiple-step fabrication procedure and in some cases requirement of special chemical or sophisticated techniques further limit wide-spread application of the aforementioned membranes.…”

“…The PDMS-modified SW can be magnetically guided and is capable of absorbing and separating oils and organic solvents from water. Gravity-driven oil–water separation results showed permeate flux as high as ∼32 000 L/m 2 h with separation efficiency over 99% …”