Creating aerogel with supercritical methanol

In previous videos, I used supercritical CO2 to dry my homemade aerogels. This time, I soaked the aerogel in methanol, then raised the temperature and pressure of the methanol itself to make it supercritical. This allows the gels to be dried without an additional solvent exchange into CO2. The downside is that it requires a chamber full of methanol at 460*F and over 1200 psi, which is a much bigger hazard than using CO2.

The aerogels dried with methanol shrank less than the ones dried with CO2, but there was still a lot of cracking, and I have yet to create a high-quality monolith.

Category:

Science & Technology

Tags:

• aerogel
• supercritical
• methanol
• TMOS
• supercritical drying
• tetramethoxysilane
• tetramethyl orthosilicate
• aerogel production
• manufacture
• DIY

[cholulo80]

great job man!

I see you changed de preassure vessel from the original's aerogel.org pipe fittin design.

what kind of pipe did you use? is inox steel?

[bkraz333]

@cholulo80 These are 2" schedule 80 steel pipe fittings from McMaster.

[cholulo80]

@bkraz333 thanks, is stainless steel right?

Im from Argentina and I tring to figure out how I suppose to make my supercritical dryer for aerogel production without killing myself in the process!

I planned to make it with stainless steel 316 or 304 pipe fittings but if is a way to make a bigger dryer with other components will be great.

thanks and keep working, you great!!

[bkraz333]

@cholulo80 It's not stainless -- just plain steel. Good luck!

[Fast2405]

Another fantastic video. :) If you get chance take a look at the videos from NurdRage. Some interesting stuff there. According to Wikipedia - One of the drawbacks of methanol as a fuel is its corrosivity to some metals, including aluminium. Methanol, although a weak acid, attacks the oxide coating that normally protects the aluminium from corrosion:

6 CH3OH + Al2O3 → 2 Al(OCH3)3 + 3 H2O

[refa42]

Haha, nice touch @ 2:11

It's like "if this thing blows up it will vaporize this whole shop but remember, always wear eye protection".

Maybe we see more FPGA stuff in the future. Or stainless steel high vacuum parts turning in your nice lathe. Doesn't matter much because your experiments are always interesting, just keep it safe :)

[kualquierkosa]

I was gonna suggest you changed your molding technique, but you already will, i was thinking the pressure to release the gel from the syringe actually fractured the gel, and these fractures only showed until you dried it. >.< so i think. Good luck in future experiments very informative, Thumbs up.

[Hobgoblin612]

if there was a slow leak and it ignited you wouldnt know because methenol burns with a clear flame! (you can only see the heat haze)

[fusionfreak2009]

You know typical steel vessels lose their structural integrity and weaken @ 350F. I would wrap your tank w kevlar or not really push that vessel to its max psi anymore. Thanks for yr post, did you happen to try decaffinating coffee w high pressure water after being subjected scfe?

[fakemadereal]

Yes, since us YouTube commenters have been known for our high IQ's.

[Th3Su8]

Are you related to Bill Nye?

Thanks for the informative, and sometimes dangerous, scientific experiments. Keep up the good work and making science interesting and fun.

[GOTJIFF223]

yes methanol and aluminum do react, im surprised you still have your aluminum washer