Microplastics are receiving a lot of attention lately due to its difficulty in removal from the environment.
Sieves and filtrations are currently the predominant way to capture microplastics in water. However, this is impractical because filters clog easily and regularly need to be cleaned or replaced.
Another issue is that it has been impossible to collect anything smaller than 0.3mm, the size of the mesh plankton net pore diameter. This is unfortunate because the majority of microplastics causing havoc are smaller than that, with unknown effects on the eco and biosystems.
A promising new method to collect such microplastics has been devised using acoustics to gather them in water. A bulk acoustic wave (BAW) device was designed and fabricated that channels microplastics, gathering them in the middle channel while water flows out the two side channels.
Read more at Shinshu University
Image: Microplastics in sediments from the rivers Elbe (A), Mosel (B), Neckar (C), and Rhine (D).
Note the diverse shapes (filaments, fragments, and spheres) and that not all items are microplastics (e.g., aluminum foil (C) and glass spheres and sand (D), white arrowheads). The white bars represent 1 mm. Image Credit: Martin Wagner et al.