Sciencemadness Discussion Board

Which transition metals does cyanide produce soluble complexes with?

bolbol - 22-7-2019 at 16:45

I was wondering if anyone knows of any sources for this information. I haven't found one that has a full coverage of all transition metals. I have many different samples of different mixtures of metal oxides produced from sulfide mineral bearing rocks. I want to know what, besides gold, cyanide will dissolve so I can selectively drop them out of solution if present.

[Edited on 23-7-2019 by bolbol]

DraconicAcid - 22-7-2019 at 18:13

I'm thinking nearly all of them form stable complex anions with cyanide (although I seem to recall that copper(II) ions will react with cyanide to give copper(I) cyanide and cyanogen).

bolbol - 22-7-2019 at 19:18

Then the question becomes whether or not these complexes will be soluble enough to be fully leached into the solution..

And I'm assuming by all, it also includes the PGEs? Considering they are present and in oxidized states?

DraconicAcid - 22-7-2019 at 20:47

Yes, the platinum group metals will form complexes with cyanide. The solubility will depend on what the counterion is. (Potassium tetracyanoplatinate(II) is only slightly water-soluble, for example.)

Boffis - 23-7-2019 at 04:32

There is a comprehensive book on the chemsitry of cyanogen that is well worth getting. It is one of my "go to" bibles. It is called "Cyanogen Compounds, Their chemistry, detection and estimation" by H E Williams 2nd ed 1948. It is usually available on amazon and is never expensives (like £3). The 1915 1st edition can be downloaded from the net for free.

The basic chemistry of the cyanide complexes hasn't change much since 1948 though there are many more mixed ligand types known now.

Hegi - 23-7-2019 at 05:29

As far as I know you can make also soluble silver and platinum cyanide complexes, for sure you can make hexacyanochromate (I have worked with this anion), cobalt(III) forms this complex too, if you take cobalt(II) and react it in inert atmosphere you will obtain beautiful green pentacyano complex. You probably know about iron cyanide complexes.. I have no more ides.