Red Copper Oxide

[TYRONEEZEKIEL]

I did a search on red copper oxide, but it came out fruitless, so I figure I will post my questions here.

 

In rifling through my inventory, I stumbled upon some red copper oxide, and am curious what the pyrotechnic difference between it and the ever so common black copper oxide (CuO) I made a control batch of

 

1.4g black copper oxide

7g Kperch

1g Linseed oil

 

 

and a variable substituting directly the black copper for red.

 

I did a side by side test, using .3g from each batch and noticed that the red oxide batch has a more significant red flame tail very similar to AP blue stars. While the Black copper had a more pure color but a much smaller flame envelope.

 

Neither were extraordinarily blue as there was not much chlorine.

 

So, I added .3g PVC powder, Not from pipe but actual PVC, to the two comps, and the results were greatly changed

 

This time I burned a .5g sample from both and the red's flame envelope greatly grew, while producing more smoke and a bluer core but still evident red tips, while the black formula produced copious amounts of smoke, had a very significant thrusty burn and again, envelope was increased.

 

I imagine the envelope increase comes more so from the increased sample size and not so much from the chlorine.

 

Other than these observations, is anyone else familiar with the effects of red copper oxide, over black?

[optimus]

Not much help, but I believe it is favoured over the black oxide in some purple formulas, at least in a couple of Italian ones I've seen.

 

As to why it is used I have no idea... it did make a lovely 'barney' type purple when I tried it.

[Twotails]

Correct me if im wrong but red copper oxide can be made from running a current through thin copper wire in a brine of electrolites right? I think it may be similer, becouse a orange/red powder settles on the bottom, and when its in the brine its an orange foam. I've been conducting this useing NaCl, but becouse of the sodium contamination i'll be moving to potassium chloride.

[WSM]

Other than these observations, is anyone else familiar with the effects of red copper oxide, over black?

 

The only reference I have mentions it as a catalyst component. I have some for that purpose.

 

WSM

[Mumbles]

In properly calibrated formulas there should be very little difference, the Copper (I) may even be more blue. When you start throwing random compositions together you will get very different results. Copper (I) Oxide does have more copper in it, so you may need to back it down a few parts and replace it with more chlorine donor or fuel or something. The red edges you saw is typical of an overoxidized mix, which would be exagerated by copper (I). Every good blue and purple is somewhat underoxidized to prevent the telltale red edges, which detracts from the star.

 

It pretty much comes down to what you have available. I do believe it will slowly degrade, especially in contact with moisture or the atmosphere. It degrades to copper (II) oxide though so big deal there. I don't think it undergoes the displacement reaction where it automatically forms Copper metal and copper (II) like some other salts.

 

I think I have a few formulas that specify it, but my computer is currently down. I will see if I can find them for you once that issue is resolved.