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Scientists break down plastic using a simple, inexpensive catalyst and air

phys.org

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Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#11

Post by PaulHoule »

wolfi1 wrote: post #10

there is also the possibility to recycle pet-bottles into food grade bottles again using just mechanical means, I know at least two European companies who provide such machines

I've seen 100% recycled PET bottles for Coca-Cola products in the US

https://www.cnn.com/2024/03/19/food/coca-cola-new-bottles/in...

and Pepsi is selling 100% post-consumer bottles in some EU countries

https://www.pepsico.com/our-stories/press-release/pepsico-co...

Those clear beverage containers are an ideal case for mechanical recycling. This company

https://repreve.com/

makes polyester fiber from recycled PET. I have a few garmets made from it and my impression is that the fabric feel is nicer than average.

Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#14

Post by tigerBL00D »

Xiol32 wrote: post #12

Break down into what? Is this also going to end up in my testicles?

It says "Leveraging the trace amounts of moisture in air, the broken-down PET is converted into monomers—the crucial building blocks for plastics. From there, the researchers envision the monomers could be recycled into new PET products or other, more valuable materials." I don't know if there's some enormous challenge hiding behind the word "envision", but I'm assuming it's a closed system until something useful comes out of the other end. The method just can't be a lot more expensive than to make the same thing/material from scratch or it's never going to gain traction.

Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#15

Post by Imustaskforhelp »

tigerBL00D wrote: post #14
Xiol32 wrote: post #12

Break down into what? Is this also going to end up in my testicles?

It says "Leveraging the trace amounts of moisture in air, the broken-down PET is converted into monomers—the crucial building blocks for plastics. From there, the researchers envision the monomers could be recycled into new PET products or other, more valuable materials." I don't know if there's some enormous challenge hiding behind the word "envision", but I'm assuming it's a closed system until something useful com…

Well let's truly hope that its not that much expensive

Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#16

Post by roughly »

jandrese wrote: post #8
kibibu wrote: post #5

Earlier quoted context omitted.

The journal article is open access. https://pubs.rsc.org/en/content/articlelanding/2025/gc/d4gc0... > Catalytic amounts of AC/MoO2 selectively convert waste PET into its monomer, terephthalic acid (TPA), within 4 h at 265 °C with yields as high as 94% under 1 atm air. I'm not a chemist so don't know if you can find a way to calculate the cost, but the authors claim that it's cheaper than current methods. The bigger d…

That's within the range of a kitchen oven. The biggest problem is that plastic is so cheap that even that relatively modest energy use may make it uneconomic compared to virgin TPA, especially if you have to clean the inputs thoroughly first.

In fairness, that’s mostly because current plastic production externalizes the cost of everything about the lifecycle before and after manufacturing and use.

Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#17

Post by culi »

What percentage is actually broken down into monomers? How much microplastic waste is left behind. Given the reliance on "ambient air" I imagine it's not 100%.

Regardless, I'm excited to hear about progress on solving the plastic waste crisis. It seems better than the current alternatives the article presents:

> "The U.S. is the number one plastic polluter per capita, and we only recycle 5% of those plastics," said Northwestern's Yosi Kratish, the study's co-corresponding author. "There is a dire need for better technologies that can process different types of plastic waste. Most of the technologies that we have today melt down plastic bottles and downcycle them into lower-quality products.

Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#19

Post by culi »

PaulHoule wrote: post #11
wolfi1 wrote: post #10

there is also the possibility to recycle pet-bottles into food grade bottles again using just mechanical means, I know at least two European companies who provide such machines

I've seen 100% recycled PET bottles for Coca-Cola products in the US https://www.cnn.com/2024/03/19/food/coca-cola-new-bottles/in... and Pepsi is selling 100% post-consumer bottles in some EU countries https://www.pepsico.com/our-stories/press-release/pepsico-co... Those clear beverage containers are an ideal case for mechanical recycling. This company https://repreve.com/ makes polyester fiber from recycled PET. I h…

Yes PET (#1) and HDPE (#2) are the two easiest plastics to recycle and the most commonly recycled

Re: Scientists break down plastic using a simple, inexpensive catalyst and air

#20

Post by culi »

PaulHoule wrote: post #7
kibibu wrote: post #5

Earlier quoted context omitted.

The journal article is open access. https://pubs.rsc.org/en/content/articlelanding/2025/gc/d4gc0... > Catalytic amounts of AC/MoO2 selectively convert waste PET into its monomer, terephthalic acid (TPA), within 4 h at 265 °C with yields as high as 94% under 1 atm air. I'm not a chemist so don't know if you can find a way to calculate the cost, but the authors claim that it's cheaper than current methods. The bigger d…

This is contrast to the pyrolysis-based "chemical recycling of plastics" which makes a mix of petrochemicals similar to what you find in the BTX stage of a petrochemical factories [1], especially for condensation polymers like PET. That is, this process produces fairly pure Terephthalic acid [2] and Acetaldehyde [3] and the first of those could be recycled into more PET. The thing is BTX chemicals and other precursor…

> about 50 cents a pound which makes it hard for any kind of recycling process to be competitive.

We've had almost a century of subsidization of the oil industry. The gov't needs to play a bigger similar role if the recycling industry is ever gonna be able to compete

We need a tax on the full lifecycle cost of plastics so we can stop treating waste as an economic externality

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