Making silica aerogel at home

I followed instructions in the silica TMOS recipe from http://www.aerogel.org and successfully produced some small pieces of aerogel in my home shop.

The two main difficulties are: 1. Getting TMOS or TEOS (the key chemical ingredient), and 2. Building a supercritical drying chamber. The components for the chamber can be bought from http://www.mcmaster.com or another source of industrial pipe fittings. You'll also need a supply of liquid carbon dioxide. I used a 20-lbs cylinder, which I bought from a local welding store. Most of the cost is in the cylinder itself, since a refill costs only $20 to $30. You may find a welding supply shop that will rent the cylinder.

Getting the TMOS is difficult since chemical suppliers are generally unwilling to sell to individuals.

The process to make aerogel is:

1. Mix TMOS, methanol, and ammonium hydroxide. Pour this mixture into molds, and wait for a gel to form.
2. Submerge the gel in methanol, and wait a day for the remaining water in the gel to diffuse into the methanol.
3. Discard the methanol, and replace with fresh methanol. Wait a day, and repeat. Repeat this process a few times over three days.
4. Transfer the gel into the supercritical drying chamber, and fill the chamber with methanol.
5. Add liquid CO2, then open the chamber's bottom valve to remove the methanol. Make sure the gels are always covered with liquid CO2.
6. Wait a day for methanol to diffuse into the liquid CO2.
7. Open the bottom valve and remove more methanol.
8. Repeat the methanol draining procedure while making sure the gels stay submerged in liquid CO2. Repeat the CO2 draining/exchange a couple times over 2-3 days.
9. Raise the chamber temperature to cause the CO2 to become supercritical. Slowly vent the chamber while applying heat to ensure the CO2 moves from the supercritical phase to the gas phase. Continue venting the chamber slowly, then remove the finished aerogels.

Category:

Science & Technology

Tags:

• aerogel
• aerogel production
• home
• making aerogel
• xerogel
• TMOS
• tetramethoxysilane
• tetramethyl orthosilicate
• aerogel.org

[lexichronicle2]

"Something I'd be itching to try with DIY aerogel would be a tiny desktop furnace. It could get white hot inside and barely warm up outside."

Someone has already done something similar too. If you google for 'thermos furnace' and similar, I think it's in popular science, and it's a tiny decomposition furnace build in a coffee thermos, using the vacuum walls as insulation. Nice. :D

[bkraz333]

@lexichronicle2 Good idea! I'll start making some small aerogel bricks.

[budforever442200]

Could you use the supercritical chamber for extracting caffeine? Place coffee beans inside the chamber, fill with ethanol, fill co2 and turn supercritical, then bleed extracted caffeine off the bottom valve?

[bkraz333]

@budforever442200 Yes, I am going to try this pretty soon. I already tried doing it with a paintball gun cylinder, and had no success. This time, I have a better CO2 setup, and will more closely follow the methods described in decaffeination process patents.

[LegendofJonnie]

Maybe an odd question, but what is machining aerogel like?

[bkraz333]

@LegendofJonnie It's very brittle like chalk or charcoal. I imagine the only way to reduce its size would be by grinding. I'll give it a shot on my next batch of larger silica gel pieces.

[Rasayana85]

Oh how I would like to have this guy as a neighbor.

[ScalesandGills]

2:05

"The Pyro is a SPY!"

[invertedlow]

Thanks for sharing. You rock.

[Benisuber1]

Do you think that TEOS would make higher quality aerogel? It's also MUCH cheaper than TMOS.

[CognitiveNetwork]

Nooooooooooooooooooooooo... it's supposed to be an Industrial secret you mother fucker!!!

[passcal87]

mlk

[kiyotewolf]

how long does aerogel last? how long does it take to decompose?

[larsruberti]

expectation will be me making earogel.

Reality is that it will blow up in my face

[lucariox2o]

soooooo...... crystal meth

[Gatuno894]

We will not manufacture the airgel, but I need all infomation to share everyone that will watch for presentation.

thank you very much

I'm in Brazil, Sao Paulo, a city of Valinhos

[Gatuno894]

bkraz333 Man I admire your work, I'm looking for step by step process of silica airgel.

I want to present an essay at the University where the airgel is the theme, and I would like to have the step by step to produce it.

I loved your videos and also the inventions. They helped me a lot how to present my essay at the university.

[jabo109k]

Great video, made me understand the process! Tks...subscribed