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Plastic to Oil – Produces 80% Oil

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Re: Plastic to Oil – Produces 80% Oil

#241

Post by Turbots »

godelski wrote: post #208
HackOfAllTrades wrote: post #201

Why do people keep falling for this? This same fraud used to pop up only every 10 years. Now it's 5 or less. I'm a PhD chemist. Please consider this: While plastics and oil are both hydrocarbons they have this important difference. Liquid hydrocarbons have short carbon chains and lots of hydrogen. Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen. That is why, when you he…

Is it hard to add a source of hydrogen? In the images they have here it looks like there is a vat of water and it explicitly says it produces H2O and CO2 gas waste (though calls the CO2 harmless). That would imply there is a source of hydrogen here. (Not an expert, just legitimately curious so I can better spot snake oil)

[dead]

Re: Plastic to Oil – Produces 80% Oil

#242

Post by TeMPOraL »

_hypx wrote: post #230
HackOfAllTrades wrote: post #201

Why do people keep falling for this? This same fraud used to pop up only every 10 years. Now it's 5 or less. I'm a PhD chemist. Please consider this: While plastics and oil are both hydrocarbons they have this important difference. Liquid hydrocarbons have short carbon chains and lots of hydrogen. Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen. That is why, when you he…

You can steam reform plastic and get hydrogen for that purpose. It will imply that you have to lose a percentage of your plastic input, but if it is just plastic waste then that is not a huge problem.

Was going to ask about that - I mean, hydrocarbon chains, by definition, contain hydrogen, so surely you should be able to use part of the input as hydrogen source (leaving concerns of practicality, efficiency and price aside).

Re: Plastic to Oil – Produces 80% Oil

#244

Post by LarryMullins »

arbitrage wrote: post #216
throwaway5959 wrote: post #214

Earlier quoted context omitted.

At that point, why not just use hydrogen as a fuel? Or better yet, just use batteries.

I can't fuel my car with hydrogen.

You could, the technology exists. The reason hydrogen fuel cells never caught on is because the production of hydrogen doesn't make economic and environmental sense. Which gets back to the root of problem with the OP claims.

Re: Plastic to Oil – Produces 80% Oil

#245

Post by LarryMullins »

mandmandam wrote: post #151
HPsquared wrote: post #139

Earlier quoted context omitted.

For tires, is anyone working on biodegradable or otherwise eco-friendly tire materials? Something that is biocompatible. Although you don't want tires breaking down and causing accidents... Tires have a lot of conflicting design requirements.

Bio tires would be great, but the more immediate, easy and efficient solution is public transport investment to reduce car use.

Tires made with natural rubber are nothing new, that's the way all tires used to be made. And I doubt it's any better for the environment, from either a microplastics perspective or a deforestation perspective.

Re: Plastic to Oil – Produces 80% Oil

#246

Post by LarryMullins »

matmatmatmat wrote: post #243
ac29 wrote: post #177

Earlier quoted context omitted.

Most of the carbon is going to end up as CO2 in the air, though.

Unless you capture it, as Amsterdam has been doing.

CO2 capture is a scam, perpetrated by the petroleum industry to make people think it's okay to burn more fossil fuels.

Re: Plastic to Oil – Produces 80% Oil

#247

Post by etaioinshrdlu »

HackOfAllTrades wrote: post #201

Why do people keep falling for this? This same fraud used to pop up only every 10 years. Now it's 5 or less. I'm a PhD chemist. Please consider this: While plastics and oil are both hydrocarbons they have this important difference. Liquid hydrocarbons have short carbon chains and lots of hydrogen. Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen. That is why, when you he…

My understanding is that polyethylene, one of the most common plastics, has no double bonds, and the exact same ratio of carbon:hydrogen as shorter carbon chains. Simply breaking the polymer into short chains should literally give you oil. Why not?

Re: Plastic to Oil – Produces 80% Oil

#248

Post by TSiege »

ElevenLathe wrote: post #31
TSiege wrote: post #25

Earlier quoted context omitted.

Fascinating and makes sense. I've recently gone down a rabbit hole on the uses of linseed oil pre fossil fuels, but it's too gummy to ever be used as a lubricant. Do you know off hand which seed oils were used for lubricants?

Castor oil was famously used as a lubricant in early WWI-era airplane engines. The fumes would blow in the pilot's face and are also a laxative.

Haha that's amazing! Hopefully the pilots weren't too phased. Thanks for sharing

Did some further digging and it looks like it does have a tendency to gum. From wikipedia, "The viscosity of castor oil at 10 °C is 2,420 centipoise,[28] but it tends to form gums in a short time, so its usefulness is limited to engines that are regularly rebuilt, such as racing engines. Lubricant company Castrol took its name from castor oil."

https://en.wikipedia.org/wiki/Castor_oil#Lubrication

Re: Plastic to Oil – Produces 80% Oil

#249

Post by jcranmer »

etaioinshrdlu wrote: post #247
HackOfAllTrades wrote: post #201

Why do people keep falling for this? This same fraud used to pop up only every 10 years. Now it's 5 or less. I'm a PhD chemist. Please consider this: While plastics and oil are both hydrocarbons they have this important difference. Liquid hydrocarbons have short carbon chains and lots of hydrogen. Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen. That is why, when you he…

My understanding is that polyethylene, one of the most common plastics, has no double bonds, and the exact same ratio of carbon:hydrogen as shorter carbon chains. Simply breaking the polymer into short chains should literally give you oil. Why not?

Polyethylene is (CH2)n, where n is in the thousands or so, or 2.00 H per C. An octane (e.g., for gasoline) would be C8H18, or 2.25 H per C. Smaller-chain molecules are even higher H/C ratio.

So even polyethylene is short about .25 H per C.

Re: Plastic to Oil – Produces 80% Oil

#250

Post by agumonkey »

otikik wrote: post #221
didericis wrote: post #218

Earlier quoted context omitted.

https://youtu.be/Zmtc22uPLd4 I’m not a chemist/someone else can offer a more detailed explanation (just love the excuse to post that song), but with most of these kinds of things the energy and advanced equipment required to go in a theoretically plausible direction for a minuscule amount of yield is usually absurd. Including turning iron into gold. (I think it might theoretically be possible to do that at this point…

The way to turn iron to gold is ancient: smelt the iron, make a weapon with it, and use that to steal the gold from someone else.

teleochemistry
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