Making supercritical CO2

Seeing how CO2 reacts under high pressure, do you think if a small amount of water / ice were added to the chamber with the dry ice, would it change to liquid as well? And if so would it become carbonated?

I know very little about chemistry, but don't evaporating liquids lower heat energy during the phase change? It's like when glass moves from hot to cold and it cracks. What if the silica beads cooled down really quickly and cracked as a result of the temperature change?

I think they look about the same still, but id have to confirm. Also, Ill have to check them under UV, i didnt think of trying that

Nile Red

cool!

Nile Red

Use a torque wrench to tighten the bolts. You should be able to calculate a ballpark torque from the expected pressure, chamber face area, and screw thread pitch. Essentially you want the bolts pre-stressed enough that they don't stretch any further when the chamber is pressurized. A different style of bolt head, such that you can install a keeper to prevent the bolts from rotating, would also speed up closing the chamber because you would only need one wrench.

Kevin Martin

this is an interesting rabbit hole. https://pubs.acs.org/doi/10.1021/ja035177i

https://www.sciencedirect.com/science/article/abs/pii/S0167577X06001637 https://link.springer.com/article/10.1007%2FBF00797533

This is a pure guess. When the co2 entered the beads it was along or formed stress fractures. When you released the pressure the structure tried to fill the voids. Since the edges of the fractures are probably monoatomic in distance, you are getting diffraction patterns....or and I doubt this, you formed some nanoparticles that are trapped in the fractures. I don’t buy this second idea. Pretty cool! Maybe you formed a layer of silicon carbide?

Wonder if you can use a little laser and measure deflection to measure refraction changes and then correlate to density. That then should give you pressure.

It was so cool, a few weeks ago I showed the applied science video to my organic chemistry teacher and he told me that he wanted to do some research on super critical CO2 but my University didn't had the founds or applications to start a research on that when he was younger

David Pelayo

did the silicon beads colour change last? Both the yellowing and the iridescence? Do they fluoresce under UV?

Quatch

No worries!

Nile Red

I tried finding something less dense, but there isn't much that works. If it's porous at all, the supercrit CO2 just immediately infiltrates it. I was thinking that the only thing that would work are some holl metal beads filled with air, but I couldn't find or easily make them.

Nile Red

What would happend if you put something a little bit less dense than supercritical CO2? Would that float as expected? Supercritical CO2 is as weird as fascinating! I really love being one of your patreons and big fan!!

I just had to downgrade my patronage and you go and post a really good video making me feel bad. Wish i could give you 50 a month

I loved seeing the beads slosh around in an invisible liquid. Great stuff as always!

No fair Ben will lend you his toys but not me. :D

Silviu T

This is awesome! Looks great.

You know what very cool about super critical CO2 being used extract Caffiene from Coffee and you can get other types of aromas from scent from materials. It a green method of getting stuff out and recycle the CO2 Red Nile.

Daniel Blake Shoemaker