Instructables

Making Copper (II) Chloride From Acid and Copper

Ok, so last 4th I made fireworks for a small- and I mean small- display, and it turned out fairly well. I only had two complaints-
a) It wasn't that colorful, as I was only using pine and palm charcoal for color: reddish orange.
b)it wasn't electrical, and took alot of visco, as I wanted everything to go off near-instantaneously.

Well, I am going to solve problem b by getting e-matches off of Skylighter, but solving a is a little harder. Then, I read that certain copper compounds could be added to create a green to green-blue color in the flame. Well, I like that idea, but I didn't know where to get the copper compounds. So I kinda left it.
UNTIL TODAY!
I found this page on making copper (II) chloride. Well, it seemed straightforward enough, so I was going to try it. I was only wondering about two things:
a) why on the description on this page about it include hydrogen peroxide, but the page does not even mention it?
b)is this safe? I guess I should be outside for the hotplate part- I can't imagine boiling/simmering HCI, inside.
c) is this even possible? Does it:
1)create a form of copper that could be used with success in pyrotechnics?
2)create copper chloride at all?

Any answers are appreciated. Even if they don't directly pertain to the topic, POST ANYWAY! Makes it more interesting.

jpoopdog4 years ago
well, i know why it mentioned the hydrogen peroxide, yes, hot hcl wil react with copper chloride in metal for, but it must be strong, now, what about copper oxide? all acids react with oxides of all sorts to produce water (h20) and a salt i think that if you rust your copper, you will get copper oxide, which doesnt colour a flame, but tdoes hold oxeygen, now react hcl will that and youll have this reation CuO+hcl== CuCl+h2O , perhaps not in that exact proprtion but it will happen all the same depending on how much oxygen the copper holds, . to rust the copper simmply run an electric current through the copper into water and into copper again, during that proceess copper carbonate will be made wich i know colours flames green, this will also react with hcl to make copper chlorie in the same way vinaar reacts with bicarb soda
NachoMahma6 years ago
. Pure Cu will add color to the flame. Don't know that it will work, but I'd try Cu powder, before trying to work with hot HCl. . . a) going by the description, all it does is speed up the reaction and is not required. Don't remember using it in HS Chem class. . b) not particularly, but with proper safety precautions you should be able to keep from harming yourself. Definitely do it outside and do NOT breathe the vapors. Don't even let the vapors get on your clothes - hot HCl is bad stuff. . c1) don't know for sure, but since elemental Cu will color a flame, I'd suspect that the chloride form is just easier to handle. It may produce more intense colors than Cu. . c2) sounds just like what we did in HS Chem class, but that was 30 years ago.
 I'm in high school chem right now and actually asked my teacher about why I always see the coloring agents in compounds rather than as you said just powdered form. If I remember correctly, the chloride or whatever the metal is bonded to aids in combustion of the metal. Whether powdered copper will work or not, I am not sure, but as soon as I figure out how to somehow powder copper, I will test how it burns. 
John Smith (author)  NachoMahma6 years ago
Thanks. It has been breezy, so should I just not do it, or would the breeze be better, as it would carry away, and dilute the fumes? I've gotten whiffs of it before, and I understand that it is not something to play around with. I had a feeling it was to speed up the reaction, as I've heard of it being used for that before
. Since you are unsure, I'd have to say it's not for you. If you decide to go ahead, make sure you stay upwind (watch out for shifts in wind direction) and wear goggles that are splash-resistant (safety glasses aren't good enough), "rubber" gloves with high gauntlets, and a "rubber" apron. Make sure you can kill the power to the hot plate from a safe distance. It sounds like a lot of hassle, but hot HCl is very dangerous. . If you need to dilute the acid, you should to be aware that the process produces a lot of heat (exothermic) and it's possible for your solution to boil and splash all over the place.
-Aj- NachoMahma6 years ago
NOTE**

when diluting an acid ALWAYS ADD ACID TO WATER. and do it SLOWLY
that will fix any problems you might have with it boiling.
lucek6 years ago
all copper compounds will release a green flame. but the intensity is the question. a fairly safe one to test is Copper oxide. (just copper rust) best advise experiment. btw sodium chloride gives you a bright yellow, and potassium chloride gives you purple. thees are both used in table salts.
westfw6 years ago
I've made CuCl from metallic copper and HCl and H2O2 (mainly for etching circuit boards, but pyrotechnics was in the back of my mind), and my experience is that HCl won't dissolve copper very well at all without the peroxide. An air bubbler helps too. An excess of copper and air seems to yield copper oxychloride, which is a more common colorant for pyrotechnics than copper chloride. The HCl/CuCl mist you get from a bubbler will drift around and cause things to corrode that you thought were "stainless."

You might have better luck finding literature on CuCl etchant, rather than CuCl prep for pyrotechnics. There's even An instructable on the process

Copper chloride OUGHT to give you BLUE flames if the flame is of an appropriate temperature. If it gets to got you'll get the green emissions of copper/copper hydroxide ions, by the CuCl- ion will give you blue.

John Smith (author)  westfw6 years ago
Thanks, that helped alot. I was going to link to that, actually. Will it work with hydrogen peroxide concentrations that you'd find in a drugstore?
Yes. IIRC, I used half 3% H2O2 and half concentrated HCl. You only need the peroxide to get started. After that, the CuCl formed has a similar effect, bubbling air is sufficient to regenerate the CuCl. A pint or so of drugstore peroxide and a half-gallon of pool acid left me with about 6oz of crystals for pyro experiments, plus half a gallon of "etchant" for PCBs.
John Smith (author)  westfw6 years ago
OK, thanks.
westfw6 years ago
BTW, "copper chloride" is not used so much in pyrotechnics, since it is hygroscopic (not so good), rather corrosive/active (you wouldn't want it combined with metal fuels for sure), and tends to form nasty sensitive compounds when it reacts with common oxidizers (Copper Chlorate is particularly scary.) Non-soluble copper salts (copper oxide, copper oxychloride, copper carbonate) tend to be preferred. Copper chloride is not so bad a starting point for getting to those as well, but copper sulfate works too and is much easier to find.
Goodhart6 years ago
Powdered anything is potentially explosive, but yes Cu powder (not sure where you'd get it from) would give you green.

The hydrogen peroxide, I don't believe it is a catalyst, but it may speed up oxidation because of the added Oxygen ion.

Um, what vessel would you "heat" it in ? It will attack most metals, to different degrees. Some chemicals and their colors: cupric ####

While it is commonly thought that the molecular species responsible for the emission of blue light in fireworks flames is CuCl, a review of the physicochemical data obtained on gaseous CuCl vapors indicates that the actual emitter is the trimer Cu3Cl3. The literature is reviewed with regard to this issue, and a few experiments which might resolve the question are proposed. (Tricopper trichloride)
John Smith (author)  Goodhart6 years ago
I was going to use a glass test tube, from a lab kit I got last year for Christmas. I've used muriatic acid before, for other things, too, so I know its danger.