Which is the best way to make cuprous chloride from cupric chloride ?
I have a large amount of CuCl2 (used to produce printed circuit boards) .
By using an excess of Cu in a CuCl2 solution in absence of Air (O2) , Cu(++) are reduced by Cu to Cu(+) and a clear solution is obtained. Is there a
way to precipitate CuCl out of the complex ?
I think I read in this forum (but now i'm not able tu find it ) about a method of reducing CuCl2 to CuCl using Dextrose and NaOH .
Could someone help me ?
Thanks .PHILOU Zrealone - 17-2-2009 at 03:00
If you warm in open air metalic Cu rods into a concentrated green CuCl2 water solution...the green solution will turn into a dark brown solution of
complexated CuCl.
When trowing that brown solution into cold demineralised water you get immediate precipitation of white CuCl.
It must be filtered and vacuum dried in the cold.visions_of_eden - 17-2-2009 at 07:47
Thanks for reply. This evening I'll try.
Btw , i found the post regarding cuprous chloride using dextrose as reducent .
1. Boil a solution of copper sulphate with dextrose and NaOH. Copper sulphate will have a methatesis with soda and produce Copper hidroxide. during
formation dextrose will make the reduction to cuprous hidroxide.
2. separate the cuprous hidroxide and rect it with hidrochloric acid, yuou will obtain cuprous chloride
Bad news is CuSO4 is required not CuCl2.
I wonder if CuSO4 could be substituted by CuCl2 .
CuCl2 + 2NaOH ---> Cu(OH)2 + 2NaCl
with dextrose Cu(OH)2 is still reduced to CuOH ?
Adding HCl would precipitate CuCl out of the solution ?not_important - 17-2-2009 at 08:23
Quote:
Originally posted by visions_of_eden
I wonder if CuSO4 could be substituted by CuCl2 .
with dextrose Cu(OH)2 is still reduced to CuOH ?
Should work. I think you actually get Cu2O, the hydroxide is not very stable.
Quote:
Adding HCl would precipitate CuCl out of the solution ?
No, CuCl forms complexes with chlorides, it will dissolve in HCl to give a brown-green solution. Pouring that into distilled/deionised water
precipitates the CuCl.
Note that you want to keep contact with air to a minimum. A small amount of elemental copper added to the Cu2O when dissolving it will be helpful.
Dissolving sulfur dioxide in the water used to dilute the HCl-CuCl solution is helpful, as is doing the same for the wash water. Also don't let the
precipitate have air pulled through it when filtering, when it's been washed enough switch to covering it with alcohol before the last of the wash
water drains off.visions_of_eden - 17-2-2009 at 13:09
Tryed adding distilled water to dark green complex and the white CuCl precipitated out. Filtered and stored under water.
After that i tryed with dextrose but i think something has gone really wrong .
I prepared a solution with excess of NaOH , a solution of glucose and added glucose to the CuCl2 solution obtained from filtration.
Then i slowly added the NaOH and instead of a red precipitate (Cu2O) a dark greenish complex formed.
What has gone wrong ?
Now i'm waiting to see if anything happens, but i really don't know what could have happed.
Any explainations ?Fleaker - 17-2-2009 at 19:16
Dissolve up copper in HCl and hydrogen peroxide. The reaction is quick and yields a very strongly green solution. This is boiled to remove any free
chlorine gas. Powdered copper, or thin bits of copper wire are added, the solution kept warm and stoppered. It takes a few hours. Add this to cold
distilled water and it's done.
CuCl2 + Cu --> 2CuCl2
Of course you can always try the numerous procedures in Brauer's Handbook of Preparative Inorganic Chemistry.
