Stannous Chloride Shelf Life

[malfeces]

Hey all, today is my 3 year anniversary as a member!! What, no cake? Oh well.
I am having some issues with my stannous chloride. Using Geos recipe, storing in a cool dry place, in a cobalt blue dropper bottle that is water tight. I keep a couple 1/4 gram beads of .999 tin in there, and it seems to only last about a month. Anyway to make go a little longer?
Thanks

 

[bswartzwelder]

I am still using stannous from the first batch I made a year or two ago. I always test the stannous with a commercially prepared gold chloride solution to make sure it hasn't expired, but so far, it's still going strong.

I purchased a 4 ounce bottle of stannous chloride anhydrous from a seller on eBay. Presently, you can get a pound for about $10. Next, I put a few crystals (3 to 5 of the larger crystals) into the bottom of a white plastic squeeze dropper bottle. Next, using a graduated cylinder I mixed up a solution of 75% H2O and 25% HCl and poured that into the bottle. Then I added 2 or 3 little pieces of pure tin shot (also purchased from eBay), put the dropper thingie back in and capped the bottle. Then I shook everything up and added the necessary label. WE HAVE NO KIDS AROUND THE HOUSE, so I store the little white bottle in the butter region of the refrigerator.

 

[malfeces]

awesome thanks! So refrigeration prolongs the shelf life, unfortunately I do have kids so that's not an option for me. Perhaps anhydrous is the way to go. I make about 30ml at a time the other way with just tin shot and hcl plus a little heat to get things going. I only recover and refine gold once every three months or so when I have enough material to make it worth while. I will check out ebay for that. Thanks!!

 

[Barren Realms 007]

Not sure why you would be having issues unless you are possibly making a weak solution. What I make is really saturated and stays outside in a plastic bottle with a flip top that I can flip open and squeeze a couple of drops out and it lasts for months.

 

[resabed01]

I store mine in a translucent dropper bottle with a snap top. This is kept out in the shed year round in all temperature extremes.
I use full strength HCl and add pure tin shot, enough so there is always a little extra. It off gasses for the first few months so it needs to vent.
Every spring before refining season I'll dump it out and make a new batch, works fine all summer long.

 

[upcyclist]

I store mine in a translucent dropper bottle with a snap top. This is kept out in the shed year round in all temperature extremes.
I use full strength HCl and add pure tin shot, enough so there is always a little extra. It off gasses for the first few months so it needs to vent.
Every spring before refining season I'll dump it out and make a new batch, works fine all summer long.

(emphasis mine)

I saw mine was still gassing, and it was time to put stuff away, so I left the dropper cap on loose and put it back in the [outdoor] plastic cabinet I use, on the top shelf. When I looked at it a week later, the dropper rubber had been was brittle and crumbled with squeeze--probably eaten by acid vapors.

Should I

• Remove the dropper cap completely until it's done gassing and store it in a beaker/watchglass combo?
• Not store it on the top shelf where acid vapors might congregate?
• Suspect the dropper bottles are cheap and not use them for acids?

 

[jason_recliner]

Plastic, squeezable, eyedropper bottles have no rubber. I bought 30x 15ml on eBay for about AUD$6.
They also don't let as much air in as glass-dropper bottles. Shelf life +++