Comment by jaggs
Comment by jaggs 7 hours ago
Oh come on. Produces 'clean energy' from natural gas? Yeah of course.
Comment by jaggs 7 hours ago
Oh come on. Produces 'clean energy' from natural gas? Yeah of course.
Would an electrochemical plasma process that takes graphene filters caked in CO2 (for e.g CNT production) be more useful?
Aluminum red mud is 40% iron.
Is hydrogen useful for plasma enhanced CVD?
Are there electrical plasma improvements to CVD specifically for CNT carbon nanotube production?
What optimizations of CVD produce nonmetallic aligned carbon nanotubes (with band gaps useful for semiconductor production for FET field-effect transistors, and integrated optical components)?
From gemini3pro, for human consideration;
> [ PECVD: Plasma-enhanced CVD] allows VA-CNT synthesis at temperatures as low as 450–650°C
> High-flux hydrogen (H_2) carrier gas is used in floating-catalyst CVD (FCCVD) to reduce the number of nuclei, favoring isolated semiconducting nanotubes over bundled metallic ones.
> Electric Field Alignment: PECVD uses the built-in electric field of the plasma sheath to guide nanotubes into vertical or horizontal alignment as they grow.
> [ Kite growth CVD with nonmetallic seeds like nanodiamond grow in tip-growth mode ]
Which would be useful for FET in Carbon-based chips
Couldn't hydrogen (cold) plasma clean a CVD reaction chamber?
I'm a hardline no-fossi-fuels ever kind of guy and yes, this is clean energy.
If you collect the pollutants before emitting them and turn them into stable products, you aren't polluting.
Ergo, clean.
There will be more atomic C in the upper layers of the Earth if you dig deep and pump out natural gas.
How long will the C atoms in those "stable product" stay there?
Burning wood is clean energy: it does not increase the number of atomic C in the upper layers. Natural gas is not, unless you find a way to store those C.
This also produces carbon nanotubes, which they claim can be used in construction.
Given that construction currently uses a huge amount of concrete, and given that concrete emits huge amounts of CO2[1], if this could partially replace concrete in construction, it might actually be clean. At least compared to what we're doing now.
I doubt foundations are going to be made out of carbon nanotubes, but they might be useful for the structure (columns, beams, etc.).
---
[1] "4-8% of total global CO2" according to https://en.wikipedia.org/wiki/Environmental_impact_of_concre...
> Except natural gas is a hydrocarbon, isn't it?
Why is that disqualifying?
The problem is combustion’s emission of sequestered carbon. If you don’t have that you don’t have this problem.
The problems with natural gas are definitely not confined to combustion. Methane leakage is a huge problem.
That and if you just encourage more exploration, and it's cheaper to just burn the stuff anyways, guess what happens in the price conscious free market?
> ignoring the dirty processing problem
You concluded it’s processed dirtily at the source based on that premise (“which means”). If you’re independently asserting that, you’d have a point.
It has nothing to do with clean energy, other than the downstream effects of cheap CNTs should the process be refined enough to scale and commercialize. The hydrogen is recycled in the process. The primary thing that it produces are CNT aerogels. However according to the paper catalyst efficiency is shit. Says less than 0.1% of catalyst particles actually grew CNTs. No wonder CNTs are currently ≥$200/kg. Needs improvement by either dramatically increasing catalyst efficiency or finding dirt cheap iron/sulfur sources.
Carbon fouling is also a major block to scale. 15-20% of carbon deposits as soot on reactor walls. At a 1MW scale thats 15-30 kg/h of crud degrading the catalytic heat transfer. Continuous cleaning or scheduled downtime would drive OPEX out of possible realities.
Hot hydrogen loops are a son-of-a-bitch and equal continuous embrittlement of pipes, valves, pumps. Seals that work at temperature. H2 Leak detection. Some real heavyweight process safety engineering here.
The reactor chemistry is solved. The paper proves it works.
The scale-up is where clean-tech startups go to burn money and die.