Sciencemadness Discussion Board

CuCl (cuprous chloride) via electrolysis of HCl

lysander - 18-9-2015 at 10:52

This thread notes that CuCl forms easily from low-voltage electrolysis of NaCl + H2O, but doesn't contain much theory.

I need a solution of CuCl in HCl, so I was thinking that I could create it in similar fashion simply via electrolysis of copper electrodes in aqueous HCl.

(Unfortunately I can't find any research specific to that, because CuCl-HCl electrolysis is a popular method of generating hydrogen, so all searches return papers on that.)

Is anyone aware of research on the electrolytic reaction I'm proposing here?

gboneu - 14-10-2015 at 18:52

Iv'd made some cuprous chloride when i was doing some experiments on pH measurements ( http://www.sciencemadness.org/talk/viewthread.php?tid=62399#... ) , iv'd made from electrolysis some KCl solution with copper wire and CuCl formation in the copper wire was very rapid, And very pure, I used 12v power supply. The problem is the more you live it to precipitate, the more ir oxidase , and Electric current also seems to increase oxidation of the CuCl

deltaH - 15-10-2015 at 01:57

Yes using a concentrated solution of HCl and copper anode would work very well. The copper(I) will be present in solution as CuCl3(2-) ions because of the high concentration of Cl-.

One word of caution though: you will need to use a porous earthenware pot immersed into the annolyte, which in turn should contain your copper pregnant catholyte and cathode inside it.

This is because if the copper salt gets to the cathode, it would simply be reduced back to copper instead of H+ being reduce to H2, which is what you want. The porous separator will allow ionic conductivity but slow down the diffusion of the CuCl3(2-) ions over to the cathode.

You might want to boil the clay pot in conc. HCl a couple of times to remove any acid soluble contaminants that could dissolve before using it.

[Edited on 15-10-2015 by deltaH]

lysander - 16-10-2015 at 08:38

Ah ha, very clever solution!