strong chlorine smell...

[patnor1011]

When I put my rinsed foils to HCl and added bleach they immediatelly started to disolve. They disolved completely and now I have nice yellow coloured AuCl. I left that sit overnight and next day when little bit agitated with glass rod it gave out strong chlorine smell again. I left that sit another night. Every time when solution is little bit agitated there is strong chlorine smell. Is that possible that I overdid bleach? What do you reckon is it safe to continue with SMB or it will be better to put in more foils from another batch? Thanks for help. Also my another question is to mix SMB with water and put that in or use SMB as powder straight to AuCl? Thanks again.

 

[glorycloud]

When doing the HCL / Clorox for dissolving the gold foils, I really add the clorox in very small increments and allow it to dissolve as many gold foils
as it can. When it seems to have stopped dissolving foils, I add just a little bit more clorox and keep repeating until all the foils finally are dissolved.

By doing this, I normally don't have to wait overnight for the excess
chlorine to gas off the auric chloride. I add the SMB powder directly
into the AuCL3 and stir well with my glass rod until I get that wonderful
yoo-hoo chocolatey brown colored cloud-o-gold swirling around. 8)

 

[markqf1]

Heat your solution to near boiling on a hotplate.
This will eliminate the rest of the excess chlorine.
After it cools you can proceed with smb.

Mark

 

[patnor1011]

yeah, I recon then that I overdid clorox. its been two nights and still smelling like hell. nevermind I have another bucket on with fingers nearly done so I will combine those foils with first batch. Thanks Glorycloud

 

[patnor1011]

Heat your solution to near boiling on a hotplate.
This will eliminate the rest of the excess chlorine.

Mark

thanks, This is not an option for me unfortunatelly as I dont have hotplate now but will get some later. I will need to remember this one. Thanks Mark.

 

[Oz]

Mark is spot on with his advice. This is standard procedure for me with chlorine and every bit as important as triple boiling with AR to remove nitric before SMB.

Patnor, while you may not have a hot plate but you could use an old/cheap coffee pot burner. The key to this is that as the temperature goes up the solubility of Cl2 gas in solution is greatly reduced.

 

[patnor1011]

Good advice with that old cofee pot/plate. I will have to go to my recycling centre and Ill surely find something useful. I am not thinking about AR at this stage altough I have some jewellry stored for later processing. I want to perfect AP first, Then I want to try out cell on pins. Thanks Oz.