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I found this article about Hypergols, specifically H2O2. It mentions in table 3 and in the body of the paper that they found that Ethanolamine with Copper Chloride reacted vigorously. In my search for relatively non-toxic hypergolic fuels, this whole paper piqued my interest. From what I can tell, although a chemistry wiz I am not, the products of this reaction would be atomized Cu, Chlorine gas, and Water/Steam. Am I right? Is there a general template I can follow for this? and can anyone explain to me the chemistry going on here, so I can be a bit smarter when I stumble on my next possibility? as a sidenote, anybody have any bright ideas that I should take a look at?

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TL;DR: The result will probably be mostly water with significant proportions of carbon dioxide and nitrogen gas. Small proportions of copper(II) oxide and hydrochloric acid may also be released. There could be other species like nitrogen oxides, chorine oxides, unburnt CuCl2, and other carbon compounds that I'm not considering.

I'm not an expert on combustion chemistry, but I think we can make some inferences just looking at the stoichiometry. According to the paper, here is what we have (in percentage by mass):

Fuel

  • 80.1% hydrogen peroxide (90% H2O2, probably 10% water)
  • 19.9% ethanolamine

Mixture: Fuel + 1% CuCl2 catalyst

Let's say we have 1000 g of this mixture. Then we have:

  • $\mathrm{H_2O_2}:~0.99 \times 0.801 \times 0.9 \times (1000~\mathrm{g}) = 713.691~\mathrm{g}$
  • $\mathrm{H_2O}:~0.99 \times 0.801 \times 0.1 \times (1000~\mathrm{g}) = 79.299~\mathrm{g}$
  • $\mathrm{ethanolamine}:~0.99 \times 0.199 \times (1000~\mathrm{g}) = 197.01~\mathrm{g}$
  • $\mathrm{CuCl_2}:~0.01 \times (1000~\mathrm{g}) = 10~\mathrm{g}$

Now we have to convert this into molecules, so we divide by the molar masses to get the number of moles

  • $\mathrm{H_2O_2}:~20.99~\mathrm{mol}$
  • $\mathrm{H_2O}:~4.40~\mathrm{mol}$
  • $\mathrm{ethanolamine}:~3.23~\mathrm{mol}$
  • $\mathrm{CuCl_2}:~0.0744~\mathrm{mol}$

Now let's normalize by the number of copper atoms:

  • $\mathrm{H_2O_2}:~282.1~\mathrm{molecules}$
  • $\mathrm{H_2O}:~59.2~\mathrm{molecules}$
  • $\mathrm{C_2H_7NO}:~43.4~\mathrm{molecules}$
  • $\mathrm{CuCl_2}:~1~\mathrm{molecule}$

So for every Cu atom, we have

  • $\mathrm{H}:~986~\mathrm{atoms}$
  • $\mathrm{C}:~87~\mathrm{atoms}$
  • $\mathrm{N}:~43~\mathrm{atoms}$
  • $\mathrm{O}:~667~\mathrm{atoms}$
  • $\mathrm{Cl}:~2~\mathrm{atoms}$
  • $\mathrm{Cu}:~1~\mathrm{atom}$

So we can make 87 CO2 molecules, with 493 oxygen atoms left over. We can then make 1 CuO, with 492 oxygen atoms left over. With that, we can make 492 water molecules, with just 2 hydrogen atoms left over. That happens to be enough to make 2 HCl molecules. Hydrochloric acid is a product in perchlorate combustion, so I think it might occur here. So what's left? Just 22.5 molecules of N2.

So in summary, my guess for the full reaction is something roughly like:

$282\mathrm{H_2O_2} + 59\mathrm{H_2O} + 43\mathrm{C_2H_7NO} + \mathrm{CuCl_2} \rightarrow 87\mathrm{CO_2} + 492\mathrm{H_2O} + 2\mathrm{HCl} + 22.5\mathrm{N_2} + \mathrm{CuO}$

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    $\begingroup$ +1 for a great answer! I've started the reopen process for the question, it needs a few more votes. $\endgroup$ – uhoh Mar 20 at 10:43

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