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PO0tyTng t1_j96oi5s wrote

Reply to comment by Beyond-Time in Scientists create carbon nanotubes out of plastic waste using an energy-efficient, low-cost, low-emissions process. Compared to commercial methods for carbon nanotube production that are being used right now, ours uses about 90% less energy and generates 90%-94% less carbon dioxide by Wagamaga

From the article: > The plastic, which does not need to be sorted or washed as in traditional recycling, is “flashed” at temperatures over 3,100 kelvins (about 5,120 degrees Fahrenheit). “All we do is grind the material into small, confetti-sized pieces, add a bit of iron and mix in a small amount of a different carbon — say, charcoal — for conductivity,” Wyss said.

Sounds pretty damn scalable to me.

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Herbert-Quain t1_j96pd0m wrote

>temperatures over 3,100 kelvins

How are commercial procedures less energy-efficient than that?!

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IPutThisUsernameHere t1_j96ptw9 wrote

For additional context, steel melts at about 2,500 F - less than half the temperature cited in this process.

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PO0tyTng t1_j96t56j wrote

It’s not like nanotubes need to be made in 1000 gallon cauldrons. I would think we would need far less material than raw/smelted steel. So it could be made in a kiln or something. Honestly though the amount of heat needed is not a hurdle in scaling this up.

Really manually intensive /precise processes like making a sheet of graphene have soooo many more barriers to scaling than simply “apply more heat”

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ReasonablyBadass t1_j99eja2 wrote

Efficiency has nothing to do with how much energy you need. It's about the ration between resource use and end product.

If other processes need less heat but produce a lot of unusable waste, they are less efficient.

Edit: also,flashing, afaik, means for only a very short amount of time. Might not be all that mich energy overall, actually

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Telewyn t1_j9779bx wrote

So, useless for everything then? This will make tiny nanotubes that can't even be woven together, won't it?

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Peantoo t1_j98n6l3 wrote

Well to be fair, the act of weaving is specifically for making tiny strips into long ropes. Maybe they just need a super small weaver?

Also, carbon nanotubes have utility beyond being cables.

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axonxorz t1_j98pbqk wrote

And multiple uses as cable. Woven into cohesive fibres that are further woven into fabric or "rope"/cable, the traditional usage. Extremely low electrical resistance means collercial scale production could lead to lower cost conductors for megavolt-scale transmission

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Skyrmir t1_j993oth wrote

The short strands are used for surface coatings, and showed a lot of novel electronic properties that just weren't useful because of material costs.

We'd all like an easy answer for a space elevator, but faster, cheaper, or more efficient, electronics is always a bonus.

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Ripberger7 t1_j976v4k wrote

Well then they should stop writing white papers and start soliciting investors.

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