Good news! I blogged here several times now in the very recent past how plastic can be recycled or upcycled!
Could it even be that especially microplastics are actually fairly harmless? Is this noise about microplastics just another case of alarmism and hysteria? Quite possible!
If you suffer from plastophobia, please seek medical treatment immediately!
The article below also repeats this very dubious and most likely politically and ideologically motivated statement: "A 2019 study revealed that we're even ingesting about 5 grams of microplastic, the weight of a credit card, each week."
"... A team of scientists out of Shinshu University has turned to sound to make it happen, experimenting with acoustic filtering to push MPs into a central channel, with branched sections filled by MP-free water that can be then released. ..."
From the abstract:
"Small plastic debris particles less than 5 mm in size called microplastics (MPs) are an emerging global ecological issue. This study developed a high enrichment microfluidic device to collect various-sized microparticles that uses four serial acoustic separations. To adopt the device for use with up to 200-µm MPs, the microchannel was widened by lowering the excitation frequency. The microfluidic device was designed for a 3.2-fold enrichment at each junction and a total 105-fold enrichment at the four junctions. The microfluidic network of the device was designed on the basis of a hydraulic-electric analogy and it worked even though only a single pump was used without multiple precise flow controllers. The collection performance of the device was evaluated based on the total collection rate that in turn was based on microscopic observations at the four junctions and the actual collection rate and the actual enrichment ratio obtained by measuring the effluents from the outlets. First, the device was evaluated separately using microparticles of 5, 10, 15, 25, 50, and 200 µm in diameter. The total collection rates were over 90% except for the 5-µm microparticles which seemed to be too small to manipulate acoustically at the lowered frequency. Finally, the device was evaluated with two example mixtures representing small MPs ranging from 200 µm down to 25 µm and very small MPs ranging from 25 µm down to 10 µm. Both the total collection rates and the actual collection rates ranged from 70% to 90%. However, the actual enrichment ratios ranged from half the designed value of 105 to the design value itself as some microparticles were slowed down and a few seemed to become trapped and attached to the microchannel walls by acoustic radiation force. Therefore, the microfluidic device was judged to be applicable to MP removal applications after prefiltration through a coarse mesh, while the MP analysis applications were judged to require improvement to inhibit the microparticle attachment used in 2D focusing. In conclusion, the serial acoustic separations could be a promising approach to highly enrich and remove various-sized MPs from environmental samples."
Filtering Pollution: A Microfluidic Device for Collecting Microplastics via Acoustic Focusing It has four serial trifurcated junctions where a 500 kHz acoustic wave is applied for a 105-fold enrichment of microplastics.
Microplastics (MPs), plastic debris smaller than 5 mm, indirectly harm the environment. They are traditionally collected and removed from water by filtering through meshes, which is inefficient. In this light, researchers from Japan have developed a high-enrichment microfluidic device that utilizes acoustic focusing to collect and remove 10–200 μm MPs from wastewater without recirculation. Its collection rates and enrichment ratios ranged approximately from 70–90% and 50–100, respectively on test samples.
Graphical abstract
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