Plastic eating catalyst could help relieve plastic waste stress
Siobhan Treacy | October 22, 2020Researchers from the U.S. Department of Energy and Ames Lab scientists have created a catalyst that could relieve some of the burden of plastic waste.
Current plastic recycling processes are not always economically worthwhile. Waste plastics are often downcycled into a lower grade and less useful material. This is a problem in tackling the growing global single use plastic pollution problem.
The catalyst can process polyolefin plastics. These plastics include polyethylene and polypropylene, which are widely used in plastic grocery bags, milk jugs, shampoo bottles and more.
The new process creates uniform and high-quality components that can be used to create fuels, solvents or lubricating oils, which have high value. The process relies on nanoparticle technology. The catalyst is made of mesoporous silica nanoparticles made of a core of platinum with catalytic active sites surrounded by long silica pores where the long polymer chains thread through the catalyst
With the new design, the catalyst could hold onto and trim longer polymer chains to create consistent, uniform and short pieces that have more potential to be upcycled into new and more useful products. With the new catalyst, the team proved that the catalytic processes can perform multiple identical deconstruction steps on one molecule before releasing.
A paper on this research was published in Nature Catalysis.
The more uses we can get out of plastics the better. At the very least we should be converting un-recyclable plastics to energy using a pyrolysis process or a WTE plant.
One of the difficulties of plastic recycling is the label and adhesive used to stick it . Second is the cap and seal arrangement. And of course, residues of content .
Since these are different from the basic plastic, difficulties arise .
One possible solution is to eliminate the label. Since PET bottles are made by expansion, a die could do the job well .
Then comes the cap, which could be unscrewed and taken off . But the ring which is attached to the cap can only be cut open .For this, an alternate heat shrunk plastic hood would do and that could carry details of manufacture, sellers brand with attractive colours .
Residues inside the bottle are difficult to remove, but for water and soft drinks that could be rinsed with water, it would be much easier .