Selectively wetting LDPE-coated meshes provide a means for recovering spilled oil from surface water, resulting from accidental release of petrochemicals into water. Additional applications for hydrophobic and oleophilic meshes exist in the food production industry and chemical synthesis laboratories.
Current methods for handling oil spills (e.g., skimming, burning, sorbents, dispersants) vary in terms of expense and effectiveness, are typically confined to a small area, tend to focus on cleanup at the expense of oil recovery, and can present significant challenges in terms of ease-of-use and safety. The use of selectively wetting substances to separate oil and water is an emerging approach. Functionalizing surfaces by applying coatings that are hydrophobic and oleophilic allows for the passage of oil while preventing water flow. These coatings, while effective, often lack durability and large-scale economic feasibility. Low-density polyethylene (LDPE)-coated meshes are durable and effective, in addition to being inexpensive to produce and remarkably energy efficient.
Oil-selective meshes are created by coating a supporting stainless steel wire mesh with LDPE, thus generating a hydrophobic and oleophilic surface that is suitable for oil-water separation. The thickness of the LDPE coating determines the size of the mesh pores, rendering them easily modifiable. At the appropriate pore size, which may vary and can be predicted depending on the environment, the amount of water intrusion and the rate of oil recovery are optimized. Oil is recovered based on capillary action and flows into a collection reservoir, requiring only external pumping to maintain the process.
Inexpensive and amenable to
Separates oil with < 1.5% water
Durable, easily cleaned, and
Stainless steel; structurally
Optimizable for a variety of