How do you convert copper oxide to copper chloride?

[billysundays]

Since copper chloride doesn't seem to be available in any of the pyro chem sites (only the oxychloride), and I'm not interested in purchasing expensive lab grade material, Mumbles (thanks again) made the suggestion to try and convert the oxide or carbonate salt to chloride salt using muriatic acid. I have no idea how to figure out how much muriatic acid to use, so if anyone knows about this, let me know. Thanks.

[OldMarine]

Here's a patent with some information:

https://www.google.com/patents/US2586579

[billysundays]

Thanks for the link, OldMarine. Unfortunately for me, that description flies over me head. I'm not that well versed in chemistry to extract a "recipe" from it.

[OldMarine]

Ah grasshopper, by posting the link Mumbles will see it and will enlighten us on the content.

[billysundays]

LMAO! I obviously have so much yet to learn.

[AustralianPyromaniac]

I'm by no means an expert but I have myself tried to produce Copper (I) Chloride so I think I will chime in here. After reading that paper it looks like there is something that has been left out (Or maybe I missed). It proposes that HCl can be reacted directly with CuO or CuO2 yielding CuCl but in acctuality that will yeild CuCl2 which, I have been informed, is not desired or substitutable for the type of 'copper chloride' these compositions call for which is infact CuCl not CuCl2. It is indeed possible to reduce the 2+ ion to a 1+ ion (CuCl2 to CuCl) by, among other things, either boiling the resulting solution with copper chips for some time, adding ascorbic acid to the final solution or bubbling SO2 through the resulting solution but none of these options are nearly as simple as the original preparation makes the process seem. If one was to undertake such an endeavour the cost and chemical knowledge required would likely quickly exceed what you seem to posses.

Furthermore, the paper referenced the drying of the product in an inert atmosphere such as one of N2 or a vaccume... sorry, but neither of those things are going to happen and without them your nice white copper chloride will turn to copper oxychloride long before its dry. I tried to get around this myself by using a toaster oven with a beaker of dry ice at the bottom and it sorta worked but it was far from ideal and it still resulted in a lot of oxychloride formation.

In short. Unless you have access to a forge capable of decomposing cupric chloride to cuprous chloride in an inter N2 environment which is the best way to do this preparation in my opinion don't even try to make your own CuCl. It's a lot of work for a greatly inferior product so idealy just find compositions that dont include it. What do you even want to use it for?

 

Regards, AP

Edited September 16, 2017 by AustralianPyromaniac

[billysundays]

Thanks for your response AP! I can really use all the help I can get at the moment. When I first posed the question, I didn't yet understand the need to specify cupric, not cuprous, chloride. Unfortunately I can't edit the OP. Sorry about that.

I'm trying to figure out a recipe for converting the "readily available to purchase cheaply from anywhere" copper oxide to the "why is everyone sold out of this" cupric chloride, a.k.a. copper (2) chloride, CuCl2, which should be easily done by adding muriatic acid to the copper oxide. Making copper (1) chloride seems to be a different matter altogether.

I'll be using it to make fire logs for coloring a large bonfire.

Basically, the question is; how much muriatic acid is used per amount of copper oxide? I'm assuming that's all I need to know in this case since it works this way for strontium carbonate according to this blog post, maybe I'm wrong.

Edited September 16, 2017 by billysundays

[AustralianPyromaniac]

Ok, that makes it a lot simpler. I would normally say go and do it yourself but I don't that that's an option so here is the process. This is assuming your using CuO (Black copper oxide) and Muriatuc Acid from the hardware store which will say it contains 31.45% HCl.

 

CuO + 2HCl = CuCl2 + H2O

 

Copper oxide is 79.5g /M so 1kg = 12.6 M

 

Seeing we need double that number of moles of HCl we can conclude we will need 25.2 M

 

Muriatic acid is 9.9M /L so 25.2M is contained in 2.6L of HCl

 

Therefor, to react 1kg of CuO you introduced 2.6L of HCl slowly to control any heat produced. You should be left with a deep green solution of CuCl2 which can then be evaporated to give an aqua powder. This can then be dehydrated in the oven but for you I think this unnecessary.

 

A few tips. Use a new bottle of HCl or the concentration will have dropped and be careful that you don't boil the reaction solution. It's unlikely but I don't know how vigorous the reaction is so be carful.

 

Regards, AP

[billysundays]

AP, your the man! Thanks for working out the "recipe". I'm sure you can tell by now I have a rudimentary understanding of chemistry, difficulty parsing molecular formulas, and the amount of time it would've taken me to figure it out on my own would've dwarfed the satisfaction of my rather humble goals. But I am trying to graduate my understanding of how the chemistry of all this works, so I appreciate you taking the time to write out how you got to that conclusion.

 

I would normally say go and do it yourself but I don't think that's an option...

 

 

Sorry, I'm not following what you meant by that. Are you advising against me attempting this? I think I have a grasp of the necessary level of precautions I need to take, unless you feel strongly for some reason its a bad idea, just let me know, I'll trust your instincts. I mean, you hit the nail right on the head in thinking to advise me to get a new bottle of muriatic acid. I just checked it, and it has a layer of what looks like powdery chlorine crystals, despite the gallon being tightly closed. Although, I can argue precision is not necessary in my case; I can err on too much HCI and let it evaporate, or I wind up converting even only 90% of the copper oxide and unlikely see any practical difference. I could say its not rocket science after all, haha!

Edited September 17, 2017 by billysundays

[Mumbles]

It's going to depend in part on what sort of HCl you can get. The most commonly available OTC is 20 Baume HCl (31.45%). The other available grade is 22 Baume (~35%). Both of those percentages are w/w%. I'll walk you though how to figure this out, so hopefully you can scale to whatever you need.

 

CuO + 2 HCl ---> CuCl2 + H2O

 

CuO - 79.545 g/mol

HCl - 36.46 g/mol

31.45% HCl has a density of 1.16 g/mL

 

You need 2 molecules of HCl for every one of Copper (II) Oxide. So for every 79.545g of copper oxide you have, you need 72.92g of HCl. To get this much HCl, you need 231.86g of HCl solution (72.92g/0.3145). This much HCl is contained in 199.88 mL (231.86g / 1.16g/mL).

 

The ratio you need is thus 199.88 mL of 31.45% HCl per 79.545g of CuO. This works out to 2.513 mL of acid per 1g CuO, which hopefully should get you to whatever scale you need. Hopefully you could follow along and figure it out if you have access to another concentration of acid.

 

This is the theoretical amounts, which are about where I'd start. It assumes everything is pure. You'd likely have to filter it at some point, as not everything will be soluble. I would also do this outdoors, as there is the possibility of some sulfide containing impurities which will make quite an odor. The resulting solution should be dark blue green IIRC. You may also want to do this more dilute to make the reaction a little less violent.

 

You only want to use glass containers for this. The solution will corrode aluminum and likely steel.

 

[Edit] Looks like AP beat me too it. Thankfully we got basically the same answer though.

Edited September 16, 2017 by Mumbles

[billysundays]

Like I said to AP, thanks for taking the time to write out how to do the math, Mumbles, I'm grateful for the help. This should definitely be enough for me to figure out a recipe in the future if I decide to convert other compounds to chlorides, like strontium or barium oxide most likley. Its unlikely I'll need to do more "lab work" than that.

 

Am I right about any excess HCI not being a problem since it'll evaporate out. If that's true, what's that powdery crystal film on the outside of the bottle?

 

I have a bucket made of HDPE(2) that I was gonna use for this, which should be acid resistant, or is the problem the heat generated in the reaction might melt the plastic?

 

What were you referring to exactly when you said "You'd likely have to filter it at some point, as not everything will be soluble." ?

[AustralianPyromaniac]

What I meant by go and do it yourself was the calculations and the research but I understand your still in the process of learning this stuff so I'm more than happy to help out :-)

 

As you said, the process for converting different chems is quite similar. I have recently be converting pottery grade barium to the chloride and then the chlorate via electrolysis for some killer greens.

 

You are indeed correct about the excess HCl not being a problem. This is because it is a gas at room temp so once the water is gone it should all leave. It's like saying that CO2 will be left behind after you evaporate soda water, it makes no sense. Lots of people seem to be conserned that it is necessary to recrystallise to remove it all. To some extent the HCl may get trapped in the crystal lattice as it dries but heck, your using it for colouring a camp fire not chlorate stars. In that case I would use an excess of CuO as it's unlikely to effect the final colour and it would elimate the excess HCl.

 

Honestly who knows what that crystal is. Assuming it's just H2O and HCl crystal formation should be impossible so it's because of some impurity or reaction. Your guess is a good as mine. A reaction with the container is highly unlikely so I have no ideas.

 

Also, a HDPE reaction container should be fine as long as you're immersing it in a larger bucket of tap water to absorb the heat produced and keeping the addition at reasonable levels. Using this technique it should stay more than cool enough.

 

Finally, what mumbles meant is when this reaction is performed it's quite possible you will be left with a sludge at the bottom. This will be some insoluble impurity which, because your CuCl2 is in solution, can be filled off with minimal product loss then you evaporate the resulting solution.

This exact this happens when I converts pottery grade BaCO3 to BaCl2 and I use this procedure.

 

Regards, AP

[billysundays]

Thanks for clarifying AP. and for the understanding. This is meant to be an easygoing project for me at the moment, since I won't have the time to get into anything too involved this season, but this is also the perfect foot-in-the-door project to get into fireworks in the future. Plus, I'm glad to be making new friends here, couldn't ask for a better community to work with.

 

As for the impurities, I'll probably just leave them in. Doubtful it'll have any consequence in this case, right? And the simpler this can get done, the better, so dirty chemistry it is.

 

Oh, that crystalline powder, it definitely contains chlorinated compounds. My hands were damp when I was gonna wipe it down with a wet rag, and my skin got irritated were I was holding the handle. I totally understand HCI is gaseous like CO2, so it must be interacting with the dust that settles on the container.

[billysundays]

I have one more question about chlorine to cap off this thread, if anyone wants to chime in. Do chlorine donor compounds in general put out alot of smoke when burned? Is it from the chlorine content itself? PVC sure did create alot of noxious smoke when I added it to the fire, and I'm trying to figure out if its because I put in too much, lowering the heat output of the fire, allowing more incomplete combustion products to escape, or if its just the nature of chlorine itself in a fire? I'm considering using chlorowax as my chlorine donor and I'm hoping its not as "smokey".

Edited September 18, 2017 by billysundays