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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

#81

Post by foxglacier »

baranul wrote: post #31
kikokikokiko wrote: post #2

Well, they used a "simple, inexpensive catalyst" and then HEATED the plastic/catalyst mysture. Nowhere in the article it gives you an estimate of the final cost of the process.

Keep seeing these "possible breakthroughs" in breaking down plastic waste, but no concrete time frames on expanding to scale nor real world costs. Meanwhile, the mountains of plastic continues. Finding it also odd that biodegradable plastics and safer alternatives are going quiet. As if the new scheme is to keep fossil fuel companies rolling, with the promise that one day a solution to get rid of incalculable mountai…

Incalculable mountains aren't a real environmental problem. People just believe that for some reason. We can just leave them there forever. The actual environmental value in recycling is reducing the CO2 emissions from making new plastic by reducing production of new plastic. I don't know if biodegradable plastic actually helps at all or just placates the people worried about the fake problem of incalculable mountains.

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

#82

Post by sokka_h2otribe »

baranul wrote: post #31
kikokikokiko wrote: post #2

Well, they used a "simple, inexpensive catalyst" and then HEATED the plastic/catalyst mysture. Nowhere in the article it gives you an estimate of the final cost of the process.

Keep seeing these "possible breakthroughs" in breaking down plastic waste, but no concrete time frames on expanding to scale nor real world costs. Meanwhile, the mountains of plastic continues. Finding it also odd that biodegradable plastics and safer alternatives are going quiet. As if the new scheme is to keep fossil fuel companies rolling, with the promise that one day a solution to get rid of incalculable mountai…

Biodegradable plastics suffer from either being hard to degraded or hard to use without degrading. It's a difficult conundrum

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

#83

Post by egypturnash »

PaulHoule wrote: post #73
piokoch wrote: post #50

There is no such a thing like "plastic". The article is about PET - polyethylene terephthalate, there are hundreds other "plastics", which different chemical propensities. The problem is not actual act of recycling, but figuring out what a given piece is made of. PET is popular - 70% of all bottles are made of it, but there are those 30%, so the most expensive part - sorting - has to be carried anyway. Plus we target…

The first few numbered plastics have different physical properties and can be sorted roughly by physical processes such as floating them on water. Past that you need more sophisticated techniques, maybe robots. Those clear PET bottles for instance are common and worth recycling, but if a brand makes green PET bottles those need to be separated from the clear ones if you want good-quality clear PET which can be used t…

When the team tested the process on real-world materials like plastic bottles, shirts and mixed plastic waste, it proved just as effective. It even broke down colored plastics into pure, colorless TPA.

-- the article

so that's good I guess

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

#85

Post by littlestymaar »

culi wrote: post #61
Gigachad wrote: post #32

Earlier quoted context omitted.

Cleanup is impossible though. How are you going to clean up a trillion nanoplastic dust particles? What is the effective difference between phasing out fleece clothing vs charging $100M for a jacket?

If $100M is what it would cost to internalize the economic externalities of fleece then that is the true fair price of the item. Anything less than that is a subsidy We are subsidizing these materials with our health and our environment. And it affects certain people more than others—usually people who have the least say in it A 100% linen shirt currently costs around $40 and, when cared for properly, can last a life…

But a $100M price tag is exactly equivalent to a blanket ban, so you're not fundamentally disagreeing with the person you're responding.

You're just over rationalizing it with 101-level economics ;).

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

#86

Post by zdragnar »

Synaesthesia wrote: post #44
lxmorj wrote: post #37

Wouldn't (fully) burning all single-use plastics effectively make them no more long-lived and problematic than burning crude oil at sea? I know that's a low bar, but it seems like at least you're getting two uses out of them at that point...

A lot of plastics are incinerated. I think it has to be at a high temperature. Of course this does emit carbon dioxide.

The temperature at which burning polymers completely eliminates particulates and CO is very close to the temperature that NOx starts to form.

Source: I did a bunch of research on rocket mass heaters (think rocket stove, not missile engine) when I built one.

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

#87

Post by audunw »

piokoch wrote: post #50

There is no such a thing like "plastic". The article is about PET - polyethylene terephthalate, there are hundreds other "plastics", which different chemical propensities. The problem is not actual act of recycling, but figuring out what a given piece is made of. PET is popular - 70% of all bottles are made of it, but there are those 30%, so the most expensive part - sorting - has to be carried anyway. Plus we target…

In Norway I know the ketchup bottles (which is made from PET) changed the labels to be also made from PET, so it could be recycled with automated recycling machines. So I think something like that is what we want. The whole bottle should be recycled as one material.

If you also avoid black colour it should be possible to recycle the plastic with automated sorting machines.

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

#88

Post by culi »

littlestymaar wrote: post #85
culi wrote: post #61

Earlier quoted context omitted.

If $100M is what it would cost to internalize the economic externalities of fleece then that is the true fair price of the item. Anything less than that is a subsidy We are subsidizing these materials with our health and our environment. And it affects certain people more than others—usually people who have the least say in it A 100% linen shirt currently costs around $40 and, when cared for properly, can last a life…

But a $100M price tag is exactly equivalent to a blanket ban, so you're not fundamentally disagreeing with the person you're responding. You're just over rationalizing it with 101-level economics ;).

$100M is certainly an overestimation and some types of pollution are more solvable than others. In general I think it's important for price tags to communicate the full price of an item

Also no need for the patronizing comment. Economic externalities are a valid criticism of market failures and you haven't provided the more convincing, "advanced economics" jargon-laden analysis you're pretending to harbor

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

#89

Post by 082349872349872 »

dinkblam wrote: post #42
gsf_emergency_2 wrote: post #39

Earlier quoted context omitted.

Because historically, volcanos are thought to prefer high value offerings like live human beings

or golden rings of power

looking at https://en.wikipedia.org/wiki/Volcanic_eruption#:~:text=Ther... suggests that if a goal is to avoid eruptions, low-water content golden rings would be preferable to the bags of mostly water that are live human beings.

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

#90

Post by ainiriand »

XorNot wrote: post #71
lxmorj wrote: post #37

Wouldn't (fully) burning all single-use plastics effectively make them no more long-lived and problematic than burning crude oil at sea? I know that's a low bar, but it seems like at least you're getting two uses out of them at that point...

Landfilling plastics avoids even putting CO2 back into the environment. Modern landfill is highly engineered and extremely stable: what goes in there stays there. Plastic starts as oil in the ground. Replacing it as solids in the ground isn't a problem.

That was always my impression, and after that you can always build a park on top!
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