Can we remake plastic waste into rocket fuel?

For Hybrid rocket motor it could work

You press Plastic in thick tube and burn interior with liquid oxygen
ISP is not good but it works, but a environment clean fuel is this not !
 
Well plastic are hydrocarbons, no ? it must be feasible to turn them into rocket-hydrocarbons, which are many and varied: ethane, methane, kerosene...
 
I know that only some kinds of plastic can be used to make that kind of rocket fuel. Such kinds like Polypropylene (PP). Polyester (PE). Polystyrene (PS) and its mixtures and analogs
 
Polyethylene is, nominally, just carbon and hydrogen, but many plastics, like PTFE, include halogen substituents, which would result in pretty toxic products of combustion. Of course, a lot of plastic waste is incinerated, so the net pollution would probably be a wash.
 
There has been work done on halogen based fuels, not to mention hydrogen-halogen fuel cells.
 
The exact quote is

Chlorine trifluoride (snip) “CTF” as the engineers insist on call-
ing it, is a colorless gas, a greenish liquid, or a white solid. It boils at
12° (so that a trivial pressure will keep it liquid at room temperature)
and freezes at a convenient —76°. It also has a nice fat density, about
1.81 at room temperature.

It is also quite probably the most vigorous fluorinating agent in existence-much more vigorous than fluorine itself. Gaseous fluorine,
of course, is much more dilute than the liquid CIF-3 , and liquid fluorine is so cold that its activity is very much reduced.

All this sounds fairly academic and innocuous, but when it is trans-
lated into the problem of handling the stuff, the results are horren-
dous. It is, of course, extremely toxic, but that’s the least of the prob-
lem. It is hypergolic with every known fuel, and so rapidly hypergolic
that no ignition delay has ever been measured. It is also hypergolic
with such things as cloth, wood, and test engineers, not to mention
asbestos, sand, and water — with which it reacts explosively.

It can be kept in some of the ordinary structural metals — steel, copper, aluminium, etc. — because of the formation of a thin him of insoluble metal
fluoride which protects the bulk of the metal, just as the invisible coat
of oxide on aluminum keeps it from burning up in the atmosphere.

If, however, this coat is melted or scrubbed off, and has no chance to
reform, the operator is confronted with the problem of coping with a
metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.
 
Polyethylene is, nominally, just carbon and hydrogen, but many plastics, like PTFE, include halogen substituents, which would result in pretty toxic products of combustion. Of course, a lot of plastic waste is incinerated, so the net pollution would probably be a wash.

Not necessarily. In one case you just light it on fire. In the other you spend a lot of energy converting it to another form and THEN lighting it on fire.
 
Or burn the stuff in an electricity-generating incineration plant. Where I live, they are fitted with exhaust scrubbers to eliminate most of the polluting chemicals - dioxins, NOx, SO2, etc. CO2 can be removed as well.
 
Or burn the stuff in an electricity-generating incineration plant. Where I live, they are fitted with exhaust scrubbers to eliminate most of the polluting chemicals - dioxins, NOx, SO2, etc. CO2 can be removed as well.
I'd like those chemicals to be put to a good recycling us, not sure what as chemistry is not my thing but would that not be the ideal?
 
That would be ideal. As it is, with imperfect sorting of waste, it's often more economical to burn the lot.
 
I`ve read an article that can actually convert particular kinds of plastic into ecosense rocket fuel As far as I understand, it doesn`t have any effect on air pollution and this rocket is eco-friendly. I guess this is a nice example of what kind of invention we must make.
 
With the mass of plastic waste we face, probably that stacking them upward would be the cleanest way to reach orbital heights. ..
I don`t how efficient this petrol will be for long space journeys. As far as I understand, it was tested only on short space flights. But I guess it`s a nice step toward ``green`` launches all around the world
 
I wonder if there is a way to use the method here (https://www.chemistryworld.com/features/recycling-clothing-the-chemical-way/4010988.article) to break down plastics to their base elements and separate them. Some could be burnt but other reused in various different combinations. After all, where there's muck there's money and lots of people scavenge century old waste sites for stuff to recycle and reuse. Perhaps we can even put out some of the underground coal, old tyres and peat that have burned for decades too?
 
This petrol I`ve mentioned before was tested recently, and the result of this test has shown that he new type of rocket fuel ( remade of plastic )is 1% - 3% better than kerosene by its energy characteristics.
 
Sorry, thought you were talking about an old joke there!
 
This petrol I`ve mentioned before was tested recently, and the result of this test has shown that he new type of rocket fuel ( remade of plastic )is 1% - 3% better than kerosene by its energy characteristics.
Then it would be great for closing the loop on the life cycle of plastic. Any benefits to rocket propulsion would be a bonus. I wonder what other types of engines are amenable to this fuel?
 
This petrol I`ve mentioned before was tested recently, and the result of this test has shown that he new type of rocket fuel ( remade of plastic )is 1% - 3% better than kerosene by its energy characteristics.
Then it would be great for closing the loop on the life cycle of plastic. Any benefits to rocket propulsion would be a bonus. I wonder what other types of engines are amenable to this fuel?
As far as I understand that this special type of rocket fuel ( remade from plastic ) is not good for long space journeys. But it can be used only for small launches. I guess that there is a bigger issue in manufacturing ordinary type of rocket fuel and the resources we need to have to make it. Remaking plastic waste is a good way how to avoid this this problem
 
There has been work done on halogen based fuels, not to mention hydrogen-halogen fuel cells.
Suddenly I'm reminded of Derek Lowe's and John Clark's thoughts about chlorine trifluoride.

Something about it being hypergolic with test engineers makes me glad my test engineering career was nowhere near rocket engines. Or John Clark's test facilities.
 
I would like to learn more about this type of rocket fuel. It's great that even the aerospace industry starts to care about the environment and develops eco-fuel. But is it as effective as traditional solid fuel?
 
But is it as effective as traditional solid fuel?
In general, not really, which means that most launch vehicles using such fuels would need more of it to lift any given payload to even a low orbit, which in turn would mean that such launch vehicles would normally need to be much bigger just to carry the extra need fuel. There are potential fuels that could possibly avoid this, as well as some design tricks (such as air augmentation, Gnom style) that could be possibly used with the less efficient ones. However, even in the best case it is likely that even the most efficient synthetic eco-fuels would remain prohibitively expensive for widespread usage.
 
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I would like to learn more about this type of rocket fuel. It's great that even the aerospace industry starts to care about the environment and develops eco-fuel. But is it as effective as traditional solid fuel?
It`s not really good for long space journeys but I guess it would be rather useful for some small launches and small launch vehicles for some microgravity missions and experiments
 
Have you ever heard about green rocket fuel that is made from plastic waste? Scientists from one space company figured out how to remake plastic waste into rocket fuel that has already been successfully tested

Plastics are polymers. Poly means many and mer means thing. Think of a chain made of many links for stretchy polymers. Think of chain mail linked in many ways for hard polymers. A common mer is ethylene

1620859188603.png

It makes POLYETHYLENE -- this is the most used plastic around. 100 million tons of it are made each year world wide. That's about 38% of ALL plastics made. 150 million tons of ethylene is made each year. Ethylene is a plant hormone and forces the artificial ripening of fruits. So 50 milion tons are used for that and 100 million tons are for plastics.

Steam cracking petroleum at 950 C breaks down oil into acetylene (CH2) and reducing temperature and pressure produces ethylene. This is the most common method, though a host of other methods exist.

Acetylene is a rocket fuel.

For comparison humanity uses 4.47 billion tons of oil each year. 7.90 billion tons of coal each year and 2.41 billion tons of methane each year.

Ethylene is a plant hormone as mentioned. Microbes have been made and bred that produce large quantities of the stuff.

1620859759772.png

Ethylene Oxide is easily prepared from Ethylene using oxygen. It has a melting point of -160 C and a boiling point of 13.5 C. It was used in Germany during world war two along with hydrogen peroxide, as a rocket fuel. It is used as a disinfectant for heat sensitive materials. At room temperature is is a carcinogenic, mutagenic, irritating, anaesthetic gas. Yet is makes a dandy monopropellant. Combining both ethylene oxide and hydrogen peroxide in a combustion chamber makes a hypergolic combination.

1620860087495.png


A little pyramid made of hydrogen atoms at the base two carbon atoms in the middle and an oxgen atom on top.

So polyethylene is relatively easily converted into ethylene oxide and acetylene again. Ethylene oxide is a known monopropellant.

This program gives the Isp of every propellant combination known.. its archived here.


The best way to get rid of the plastic pollution problem is to

1. Put it in perspective in comparison to other problems, and know that academics live by creating problems.
2. Get the plastics industry together to make biodegradable plastics that break down into useful stuff.

This latter need not be more costly. In fact, I recall when I workd for the Federal EPA fresh out of school, back in the day, polyethylene became a problem then because manufacturers put stabilisers to make PET bottles UV resitant. UV light breaks down plastic in the environment. That's why tires are black. They used to be white. They have carbon in them to stop UV degradation. Anyway, remove the stabiiser would be an easy thing to do. Adding materials that have a timer on them and cause the thing to break down at a date certain would also work. People who are clueless about chemistry don't know these things. Chemists do!

View: https://youtu.be/KWJpKNQfXWo


So its child's play to put a stabiliser in plastic that switches off at a fixed time after fabrication.

Its complicated but its easy to do.

Like I said, academics advance their careers by finding problems and MANAGING THEM not SOLVING THEM.

View: https://youtu.be/ERj3QeGw9Ok
 
Acetylene is a rocket fuel.

Not a good one. Above 29 psi, it has a tendency to detonate if it gets sparked, shocked or over-heated. These *should* be avoidable in a proper rocket designs, but the failure mode is sufficiently spectacular that you'd have to be insane to use it as an important fuel in a sizable rocket.
From Clark "Ignition:"

But pure liquid acetylene was just too dangerous to live with — having a lamentable tendency to detonate without warning and for no apparent reason.


The ALASA program wanted to use a nitrous oxide/acetyelene mixture as a monoprop for a small air-launched sorta-SSTO, but ALASA went nowhere, except for the bits of it that detonated:

As of November 2015, DARPA had conducted four subscale static tests of the propulsion system on test stands. These tests were anomalous and pointed to the need for additional tests as part of refining the engine design and assessing the viability of the mix for use as a safe monopropellant. Boeing led two subsystem tests in Promontory, Utah in August 2014 and April 2015 aimed at learning how the pre-mixed propellant reacted to different temperatures, pressures and atmospheric conditions. In both tests, the propellant exploded.
 
Acetylene is a rocket fuel.

Not a good one.
Agree acetylene has challenges.

I never said acetylene was a good propellant.

I was intrigued by Rocket Lab's high density (1.78 g/cc) monopropellant.

View: https://youtu.be/gB8LEHwfXPc


Rocket Lab's monopropellant consists of carbon nano particles mixed with hydrogen peroxide that got reasonable isp at high density which translates to low structure fractions. DARPA usually throws out massive fails to cause folks to come to wrong conclusions, which is appropriate for strategic technology.

Now, when a fuel and oxidizer come together, unless they're hypergolic, they do not react unless there is an activation energy applied. So, pure carbon nanoparticles extracted from pyrolysis of methane, and chilled high test hydrogen peroxide are quite stable! Yet are easily detonated with a small amount of silver nitrate injected into the combustion chamber. Hydrogen peroxide puts out high temperature oxygen which ignites the carbon.

Nano particles of lithium suspended in hydrogen burned with oxygen has higher Isp than lox lh2 alone.

Hydrogen peroxide mixed with kerosene has relatively high density and is somewhat stable.

Nanoparticles of solid hydrogen peroxide with liquid methane is another variant.

BP of O2 is same ss MP of methane so a colloidal suspension of solid methane in a lox tank is another high performing monooropellant.

Frozen oxygen in a liquid hydrogen suspension is yet another mix.

Solid flourine particles and lithium particles floating in a liquid hydrogen suspension gets 5.5 km/sec Isp and are easier to manage than liquid or gaseous flourine.

Dr vonEschen taught me propulsion physics and chemistry at OSU. Von Eschen worked on this in the 50s and 60s.

Dr Gregorek worked on SR 71 and Have Blue back in the day and taught me aerodynamics.

With low structure fraction and high Isp you can have substantial ssto capability.


https://link.springer.com/chapter/10.1007/978-94-010-0017-8_49

View: https://www.youtube.com/watch?v=KqZDHBe2KlE

Basically a flying wing no body that has air augmented tri propellant rocket that takes off from a runway accelerates as it flies ever more obliquely and ends up flying one wing tip forward one aft as SSTO.

1-1/exp(9.4/5.5) = 0.819 propellant

0.031 - structure (2010)

0.150 - payload !!!

Or

0.081 - structure (1980)

0.100 - payload !!

Or

0.121 - structure (1950)

0.060 - payload !

Good as any tsto rlv even with 1950 hardware and structure fraction.

Crazy propellant though!

*****
1620886644899.png
1620886677699.png

My friend Jordin Kare worked at LLNL back in the 1980s and 90s and project Mockingbird use H2O2 oxidizer with RP1 fuel. Rocket Lab's VLM is very much like this imho.

Putting up a nano satellite quickly from anywhere in an uncharted orbit to surpise an enemy, stay up one orbit and land at the launch site, with surveillance data that is never radioed anywhere, provides a substantial covert capability.

A vehicle large enough to launch a pilot, say a 3 ton system that masses 30 tons at lift off with high density propellant, and HTOL capability so you can operate from a runway. With only a 2 meter diameter fuselage with high density propellant.

1620887088787.png
A tinier more capable version of Philip Bono's Space Marine Carrier -- again Ideal for Covert Operations

1620887276714.png

Of course Bono's ICARUS project could propel a battle group to any point on Earth, and return the empty after the payload was discharged. A tanker rocket flying back to the battle field with a cargo rocket could pull troops and equipment out equally rapidly.

A smaller 30 ton system that carried 3 tons payload -- the same as a DC 3 -- or a 0.9 tonne payload the same as a Honda Jet you cna fly 745 nm and back 12 minutes each way. This range is extended if you drop off a payload and fly back empty. You can also develop a tanker versiion that refills and lets you extend range that way.

So a high performan monopropellant provides a vehicle to launch 3 ton payload up to 745 nautical miles away from a submarine missile launcher and fly to a spot, land drop off agents and/or supplies, and extracts agents and/or supplies, and flies back and land back as the sub, or onward to another sub or aircraft carrier and then withdraw.

Flights of about 12 minutes each way.

Relevant data to calculate this here;



1620885412651.png
theta is the angle between the take off point and the landing point of a ballistic vehicle with zero lift. sqrt(2gR) = 11.18 km/sec escape velocity.

So, with a 9.4 km/sec delta vee you get to orbit and back with gravity drag and air drag. A 4.7 km/sec delta vee

4.7 km/sec = 11.18 km/sec * sqrt(sin(t)/(1+sin(t))) --> t=0.216353 radians (12.396 degrees)

The circumference of the Earth times 12.396/360 = 745.1 nautical miles in 12 minutes.

So a fellow can talk via Skype in the morning through a VPN from a sub off the Chinese coast, that spoofs that he's calling from DC, to a Chinese leader. Take an hour break for lunch. Fly up to 745 nmi inland, pick up agents drop off agents, pick up contraband, drop off contraband, get up to all sorts of mischief. Fly back, and have another call after lunch from the sub with the same spoof. Then, fly from the South China Sea to Mcclean Va near DC in 37 minutes. Take a car from CIA HQ to a dinner with the Chinese ambassador -- any report that he was in China stirring up various ethnic groups against the Chinese would be dismissed as impossible.

That's what this tech could do in these sorts of programs.

Of course, a ballsitc biz rocket is a dream -- and that would be awesome too! haha.
 
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That would be ideal. As it is, with imperfect sorting of waste, it's often more economical to burn the lot.
A relatively simple pyrolysis setup will allow you to convert bulk trash plastic into meh-quality diesel fuel. Basically, and a bit oversimplified, you jam a bunch of plastic into a sealed airtight container and then heat it way up. Without oxygen to burn it, at high temperature and pressure the polymers depolymerize and you end up with a thin goop of toluene and styrene and a bunch of other burnable liquids. The heat required to run the system can be produced by burning some of the trash. Something like 50 to 60% of the original plastic can be turned into liquid fuel this way, the other 40% turned into heat, CO2, H2O and whatever else comes out of the mix. The liquid fuel can be further distilled, or just burned straightaway in diesel generators. I imagine turbogenerators would well tolerate this sort of thing.

View: https://www.youtube.com/watch?v=1STaZYZ-P1w


I've often wondered if it might be feasible to take, say, obsolete crude oil tankers and modify them: convert them to electical propulsion, power provided by turbogenerators burning crap-plastic diesel. The diesel is produced on board by burning plastic fished out of the ocean itself. So it would make sense to tool these boats around in the more polluted regions, scooping up trash as they go. Would it make economic sense? Probably not.
 
That would be ideal. As it is, with imperfect sorting of waste, it's often more economical to burn the lot.
A relatively simple pyrolysis setup will allow you to convert bulk trash plastic into meh-quality diesel fuel. Basically, and a bit oversimplified, you jam a bunch of plastic into a sealed airtight container and then heat it way up. Without oxygen to burn it, at high temperature and pressure the polymers depolymerize and you end up with a thin goop of toluene and styrene and a bunch of other burnable liquids. The heat required to run the system can be produced by burning some of the trash. Something like 50 to 60% of the original plastic can be turned into liquid fuel this way, the other 40% turned into heat, CO2, H2O and whatever else comes out of the mix. The liquid fuel can be further distilled, or just burned straightaway in diesel generators. I imagine turbogenerators would well tolerate this sort of thing.

View: https://www.youtube.com/watch?v=1STaZYZ-P1w


I've often wondered if it might be feasible to take, say, obsolete crude oil tankers and modify them: convert them to electical propulsion, power provided by turbogenerators burning crap-plastic diesel. The diesel is produced on board by burning plastic fished out of the ocean itself. So it would make sense to tool these boats around in the more polluted regions, scooping up trash as they go. Would it make economic sense? Probably not.

Correct! Upgrading the products with hydrogen improves the quality of the resulting liquids improving yeilds above 75% and vastly improving quality.

 
This may be off topic but, are we not better off taking waste plastic and turning it into building materials? Lightweight panels would be ideal for emergency shelters in refugee situations and general emergencies. IMHO of course.
 
This may be off topic but, are we not better off taking waste plastic and turning it into building materials? Lightweight panels would be ideal for emergency shelters in refugee situations and general emergencies. IMHO of course.
That would require a lot of transportation. But fuel in general is useful pretty much *everywhere.*
 
Just a thought vis-a-vis locking carbon IN to a system rather than burning it and the cycle of pollution continuing.
 
*****
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My friend Jordin Kare worked at LLNL back in the 1980s and 90s and project Mockingbird use H2O2 oxidizer with RP1 fuel. Rocket Lab's VLM is very much like this imho.

98% Hydrogen Peroxide = non toxic?

Kerosene = non toxic?

Afraid, not so on planet earth. (Just try putting 50% concentrate HTP on a bit of your skin and you’ll understand)

Also at those very high concentrations, HTP can experience spontaneous deflagration even without the presence of a fuel.
 

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