It should be noted that with a ferro cyanide leach the uv conversion to cyanide is, assuming enough uv is present as sunlight etc, pretty well completely to the cyanide side of the equilibrium.
In the case of the ferri cyanide leach under the same uv conditions the conversion to cyanide is minimal.
However this is an equilibrium condition and any effect which removes cyanide from the solution will cause some more of the ferri cyanide to convert to cyanide.
Locking up some of the cyanide as gold cyanide will effectively remove that cyanide from the equilibrium and some more of the ferri cyanide will convert to cyanide in order to maintain the equilibrium.
Thus a solution of ferri cyanide will have most of the ferri cyanide as ferri cyanide with only a small amount converted to cyanide.
This means that there is a reserve of ferri cyanide in solution available for the production of cyanide if any of the already converted cyanide should be locked up as gold cyanide.
If you have a lot of time available and wish to be using the safest possible cyanide type leach then use the ferri cyanide leach.
If you are willing to trade off some of the safety buffer for time then use the ferro cyanide leach.
Deano
In the case of the ferri cyanide leach under the same uv conditions the conversion to cyanide is minimal.
However this is an equilibrium condition and any effect which removes cyanide from the solution will cause some more of the ferri cyanide to convert to cyanide.
Locking up some of the cyanide as gold cyanide will effectively remove that cyanide from the equilibrium and some more of the ferri cyanide will convert to cyanide in order to maintain the equilibrium.
Thus a solution of ferri cyanide will have most of the ferri cyanide as ferri cyanide with only a small amount converted to cyanide.
This means that there is a reserve of ferri cyanide in solution available for the production of cyanide if any of the already converted cyanide should be locked up as gold cyanide.
If you have a lot of time available and wish to be using the safest possible cyanide type leach then use the ferri cyanide leach.
If you are willing to trade off some of the safety buffer for time then use the ferro cyanide leach.
Deano