tackling a DIY COIL O2/I2 chemical laser for fun

I was reading up on the COIL project and I was thinking about wether or not it is feasible to make a small homemade COIL IR laser with everyday materials.
Granted getting Chlorine is tricky but not impossible. Chlorine can be produced via a chlorine generator. (HCl (aq) + Mn02) and Iodine is readily available in solid form from labs.

I have a (hobby) background in Chemistry and I sometimes teach chemistry Gr.11/12...

I'd like to see what the reaction vessel looks like for the laser. I am curious!

Anyone else interested in Chemical lasers? I think it could be a lot of fun

What form of chlorine? I've seen it in granule and liquid form here for pools?

What form of chlorine? I've seen it in granule and liquid form here for pools?

Click to expand...

Thats normally Sodium Hypochlorite or Calcium Hypochlorite (Or something similar)

For this I would imagine he needs pure Chlorine that is either in gas or liquid form and is yellow in appearance.

jaycey said:

Thats normally Sodium Hypochlorite or Calcium Hypochlorite (Or something similar)

For this I would imagine he needs pure Chlorine that is either in gas or liquid form and is yellow in appearance.

Click to expand...

right. I'd need pure elemental Chlorine which is NOT solid but a green gas.
Chlorine is solid at below -102c.

Anyways, to make a chemical laser would be a real challenge but the output would be very high, say a few 100 watts for a small laser since we are using a chemical reaction instead of electrical energy. There is many times more energy locked in the bonds or forming bonds of chemicals than we can make using electricity. (at current)
I2 and H2 and H2 +F2 can create wicked amounts of heat and light when added together! I personally have seen H2+F2 and it is very explosive and makes amazing amounts of heat. A small reaction will melt a pyrex glass reaction vessel in seconds! The byproduct is HIGHLY toxic and corrosive.

Aliright.. just found a patent that uses Iodine as the lasing medium..
I think I am on to something! output is ~1.6um far IR range!

Now I just need some Borosilicate glass!

I think borosilicate is pyrex. You may need quartz glass. The HF gas will etch most anything.

HMike

Right Pyrex can be Borosilicate or Soda-lime (in cooking ware).

Quartz glass I don't think will work to make a laser like this. Doesn't have the thermal shock characteristics!

HF will eat quartz glass wouldn't it? add HF to water and you get hydroflouric acid right? if so, then it will eat quartz easily and rapidly anyways... however, given he was talking about chlorine, I am guessing it's intended to be a HCl not a HF reaction. Just guessing here, been too long since I was a gr.11/12 listening to someone teach chemistry....

Part of the reaction vessel is made of 1" thick Borosilicate the other part is metal.
My guess is it is coated with platinum alloy. The reaction takes place at supersonic speeds so the exhaust is blown out of the reaction chamber before it has a chance to react with the alloy or the pyrex.

HF is Hydrofluoric acid just as HCl is a gas. It needs to be Aqueous to be useful. right!

Now you have the idea. Get the reaction products out of the laser fast. The fire in a jet engine never touches the burner ring because of the velocity.

HMike

Hemlock_Mike said:

Now you have the idea. Get the reaction products out of the laser fast. The fire in a jet engine never touches the burner ring because of the velocity.

HMike

Click to expand...

I was able to get some of the drawings for the COIL project. It involves injecting a Mixture of Neon and Oxygen at supersonic velocity, then Iodine vapour is injected and at exactly this time the mixture is charged with about 12Kvdc which ignites the mixture producing longwave IR light at the far end of the resonator. This reaction happens in a few microseconds (or less). The exhaust is vented outside the aircraft.

There is another version of this laser that only uses Iodine vapour in a sealed tube, which produces the same kind of light but at lower energies.

You would need to use -singlet- oxygen for it to work in any case, since that is what transfers energy to the iodine. The chlorine in the COIL serves to nother purpose than to create the singled oxygen. This must be produced on site or in the laser as it is rather unstable, and cannot be stored for any length of time (it will 'decay' into ordinary triplet oxygen, if it doesnt react with something else it gets its hands on).

If you were to build a chemical laser (which would be a crazy expensive and dangerous adventure), perhaps the AGIL is a better choice. Still, this uses a number of extremely hazardous gases, including HN3, NF3 and HI.

One major issue with chemical lasers is that they (nearly always) involve HF as a reaction product. HF is not just a 'stronger version' of HCl, but also a very potent poison that cannot be just vented off, even neutralizing it is tricky.


All in all, I'd say the chanced of getting yourself (and others) killed are larger than those obtaining a functional laser when attempting a homebrew COIL or AGIL.

The chemicals involved are just so dangerous that even most experienced chemisty professionals would not touch them with a 10 foot pole.

true, however HF is commonly used in glass etching in 15% vol. IT is highly toxic and corrosive. The Neon acts as a gas to help with ionization at lower voltages.
The more I read about making a chemical laser the more problems start creeping up.
You'd need a chem lab to make the laser and a properly built resonator or you risk an explosion or fire. hmm neither do I want.

And a specialized chem lab at that... I've done plenty of practical lab work involving chemicals most would consider 'very dangerous' during my chemistry masters. With experience you tend to see dangers differently, but these chemical still fall into 'please do that somewhere else' category.

It is unfortunate that there are no chemical reactions with safer materials that can yield a viable laser.

One thing that could be interesting to build is a KrF or XeF exciplex laser. These are electrically pumped and similar to the nitrogen/TEA laser, but more efficient. They operate in the near UV like the nitrogen laser, but could perhaps be good for pumping dye lasers.

I'm not sure how difficult practical construction would be - i presume its comparable to the nitrogen laser, but with the added problem of keeping a sealed laser cavity to keep the expensive noble gas and reactive fluorine contained.

One of the reactants needs to be in a super-sonic stream. It's not something you can do.

Older thread, but still interesting ^^

The gases (inlet and exhaust) are extremly dangerous, but I know that is is interesting as hell to create such a powerful laser.

Just an idea: To minimize hazerds: Work with small portions of chemicals and make kind of a "pulse laser"...would still be dangerous as hell...and super-expensive.