Research group finds way to turn plastic waste products into jet fuel

https://phys.org/news/2019-06-group-plastic-products-jet-fuel.html

by curtis • 7 years ago

63 36 7 years ago

dTal4• 7 years ago

Nice achievement, but I just don't see the environmental angle. The article implies that this might help solve the ocean plastic problem, but the plastic in the ocean isn't the plastic we carefully collected - it's the plastic that "got away". We won't be turning that into jet fuel any time soon.

And of course, taking the larger view, plastic is still made from fossil oil. Making it profitable to burn it is not going to help CO2 levels. The CO2 problem is larger than the ocean plastic problem, and even if we could turn ocean plastic into jet fuel - it's probably a bad trade.

carlmr• 7 years ago

We probably can't turn ocean plastic into jet fuel, but if there's an economic interest in converting plastic to jet fuel we could learn the future amount of plastic that ends up in the ocean.

Recycling has failed because it needs strict adherence and even then the products from plastic recycling are rarely the nice kind of plastic you need to build consumer goods.

chr12• 7 years ago

If there was a use for collected plastic, a lot less of it would "get away", currently most of collected plastic ends up in landfills anyway. Burning jet fuel obtained from plastic would not decrease CO2 level, but it would not increase it either, as there is lots of other jet fuel to burn.

helloguillecl• 7 years ago

It would increase it if it leads to more fuel supply.

dTal4• 7 years ago

If it were profitable to turn plastic into jet fuel, that would imply that plastic-derived jet fuel is cheaper. If the price of jet fuel goes down, more gets burned.

perfunctory2• 7 years ago

I think you are right. Going fossil -> plastic -> fossil doesn't sound super efficient. And single use plastic should be just banned.

inflatableDodo2• 7 years ago

This tech could be useful in a majority renewable economy. If we assume that there is a certain amount of single use plastic that fulfills useful funtions that are hard to replicate, then turning that into jet fuel is kind of useful, as jet fuel needs high energy density and is one of the things we probably are not going to electrify any time soon. The CO2 is not new emission, but is just displaced, plus any CO2 cost of the process, which is somewhat reduced if the rest of the power and transportation has already transitioned across to other power sources.

This is not a way of solving anything per-se, but is a potential technology in an economy where we have already banned burning oil that hasn't been used a few times, and then only in things that absolutely require it.

dTal4• 7 years ago

The CO2 is not new emission, but is just displaced

How do you figure? It wasn't going to be burned before. Now it is.

The sustainable way to make jet fuel would be some kind of renewable-powered carbon sequestration - for example, the process described in the paper, but fed with biomass. Burning old plastic is just fossil fuel with extra steps - looked at another way, it's a way to make fossil fuel cheaper by making it earn money as plastic before it gets burned. It's not a win.

jvanderbot• 7 years ago

Unless plastic gets away because there isnt a high enough price per kg to incentivise collection (sadly, by homeless and poor probably).

This could raise price dramatically for post consumer plastic.

stronglikedan• 7 years ago

isn't the plastic we carefully collected - it's the plastic that "got away".

From what I understand, it is the plastic we carefully collected, but didn't properly dispose of. Instead, it was sold to someone else who wasn't so careful or of dubious morals, and they didn't let it get away, they just plain threw it away. If that's truly the case, then hopefully we could cut out the inept or unscrupulous middlemen, and use it for something instead of disposing it.

3327• 7 years ago

The only question that matter is net yield of energy per energy expended vs cost.

roca• 7 years ago

No it's not. Converting renewable energy into liquid fuels is valuable in itself.

pjc50• 7 years ago

There are already different processes for this, including a rather nice one developed by the US Navy which takes CO2 directly from the ocean. Unfortunately it can't avoid being more expensive than fossil liquid fuels, which is why we have to campaign against exploration and drilling.

beat• 7 years ago

Net energy yield matters, yes, but assuming a negative net energy (seems reasonable), we could still get the negative from renewable sources.

Maybe I read too much science fiction, but I see a day in the future when we deploy autonomous technology at scale to deal with the greenhouse gasses and waste plastics of the fossil fuel era - little (or big) robots/factories that just take in energy from the Sun and use it to convert old waste into a manageable/useful form.

Realistic? I dunno. But it's certainly more hopeful than the Malthusian dystopia of shaming people for staying warm and eating and traveling.

empath752• 7 years ago

Isn’t this just burning more fossil fuels?

bloak2• 7 years ago

If some of the jet fuel comes from plastic waste instead of from the ground that might result in burning less fossil fuel, compared to the situation in which the plastic waste goes into landfill. However, as long as people are still burning coal to make electricity (which still happens in China, India, Australia, ....) I suspect that even less carbon would be released into the atmosphere if the plastic waste were burnt in a power station rather than turned into jet fuel.

empath752• 7 years ago

How much would be released if it were just put into landfills?

kwhitefoot• 7 years ago

How effective is it at converting plastic contaminated with food waste. The vast majority of plastic from my household is food packaging which is really quite expensive to decontaminate.

regularfry• 7 years ago

That can be autoclaved off, probably in the same process.

twertwtwetqew2• 7 years ago

Turning plastic into fuel is probably the only practical way to re purpose it.

Food, different feed-stock, ect, are all small details when you're operating at high T needed to cleave bonds to make fuel. Cleaved bond -> food molecule is no longer food

Recycling never cleaves any bonds, so the food is still there causing problems.

perfunctory2• 7 years ago

This is the kind of project the fossil industry would invest in. What we need instead is industry transformation away from fossils to renewables.

techno_modus• 7 years ago

Adidas is producing millions of its shoes using ocean plastic: https://mymodernmet.com/adidas-parley-sustainable-fashion (and these shoes can be then turned into jet fuel).

bkrn• 7 years ago

I think at this point they've moved to just "intercepting" plastic before it makes its way into the ocean. From the parley website:

"In remote areas, we establish systems to intercept plastic waste before it ends up in landfills, gets burned, buried or tossed into rivers or oceans."

So still might be more interesting than the recycled water bottles everyone else is sourcing but maybe disingenuous for them to be using the "ocean plastic" language still.

Iamgroot1992• 7 years ago

Love this idea but as another user has pointed out, it's the plastic that 'gets away' that we should be concerned about. Similarly, microplastics in the ocean are - and will continue to be - a massive problem. A great concept, but sadly only one cog in a very confusing machine.

blacksqr• 7 years ago

The paper's abstract is intriguing, and kind of buries the lead. The waste plastic angle is a bit of a headline-grabbing red herring. The authors claim they can turn straight-chain hydrocarbons into aromatic ring molecules, which I believe traditionally has been very hard. There's nothing special about waste plastic as a source of straight-chain hydrocarbons, they could be obtained from a variety of biomass sources.

Traditionally the only economical source of aromatic molecules has been distillation of petroleum. An economical way to turn biomass-derived simple hydrocarbons into aromatics could be revolutionary, as a path for making fuel as well as a range of other high-value compounds, like phenolic plastic resin.

dmos62• 7 years ago

The article is vague. It says that the process recovers 100% of energy from plastics they tested. What plastics did they test? Also, there isn't a discussion on energy efficiency of the process.

DigitalVerse• 7 years ago

As a few people have pointed out, this feels a lot like an attempt at solving one environmental problem (proliferation of waste plastic) by exacerbating another environmental problem (burning more fossil fuels). But if it took off, it could potentially serve as something of an intermediary step between our fossil fuel economy and a renewables-based economy. After all, the switch from horses to automobiles took 50 years. (https://thetyee.ca/News/2013/03/06/Horse-Dung-Big-Shift/, https://www.mnn.com/green-tech/transportation/blogs/horses-h...) A similar shift to renewables could easily take as long or longer.

SamBam• 7 years ago

Exactly. From a carbon/global warming sense, this is actually worse.

Plastic is carbon that never went into the atmosphere. It's actually nicely stored away, wildlife effects aside. Once you burn it, it's like you were burning oil.

twertwtwetqew2• 7 years ago

Oil in the ground is also carbon that wasn't in the air.

If the amount of jetfuel consumed stays the same, the amount of CO2 going into the air stays about the same. Could slightly increase or decrease depending on the processes' efficiency compared to the marginal oil producers' efficiency.

ars• 7 years ago

It's only worse if people fly more as a result. Otherwise you are just replacing one energy source for another.

This alone doesn't mean more energy is being used.

curtis• 7 years ago

Fuel made from recycled plastic will displace fuel made directly from petroleum. So it will make the first problem (disposing of used plastic) better while not making the second problem (carbon dioxide emissions) any worse.

Obviously this isn't useful if we manage to eliminate fossil fuels altogether, but we're a long way from that.

Research group finds way to turn plastic waste products into jet fuel

Related Stories