[sslaptnhablhat]

I had found an old, fairly active gas mantle in my attic. It got about 3,700cpm using a NetIO geiger counter and an SBM-20 GM tube. I'd done some research (Wikipedia FTW) and found that gas mantles are a very thin cotton net, impregnated with Th(NO₃)₄, soaked in an Ammonia solution, and dipped in collodion (Some Cerium Nitrate is also used, but I don't yet know how to separate it and purify the Thorium Nitrate, not that I really care so much either). Assuming the collodion formed a barrier and stopped the Thorium Nitrate from dissolving, I went ahead and cut it into small pieces and simmered it in 100C water for about 15-20 minutes, probably not long enough for much Thorium Nitrate to dissolve. I'm now left with a jar with a lot of (not radioactive) water and (1300cpm more radioactive, ironically) cotton. This was a more-or-less completely failed experiment and I'll try again later and I'm going to boil the water down anyway, just thought I'd share this experience.

[Arkcon]

I had found an old, fairly active gas mantle in my attic. It got about 3,700cpm using a NetIO geiger counter and an SBM-20 GM tube.

I'm glad you did that, modern gas mantles use a different element other than thorium.

I'd done some research (Wikipedia FTW) and found that gas mantles are a very thin cotton net, impregnated with Th(NO₃)₄, soaked in an Ammonia solution, and dipped in collodion (Some Cerium Nitrate is also used, but I don't yet know how to separate it and purify the Thorium Nitrate, not that I really care so much either).

Well, that's what's applied to the gas mantle.  But the first firing may change things.  I'd look into that.

[sslaptnhablhat]

I'd done some research (Wikipedia FTW) and found that gas mantles are a very thin cotton net, impregnated with Th(NO₃)₄, soaked in an Ammonia solution, and dipped in collodion (Some Cerium Nitrate is also used, but I don't yet know how to separate it and purify the Thorium Nitrate, not that I really care so much either).

Well, that's what's applied to the gas mantle.  But the first firing may change things.  I'd look into that.

Turns out the collodion is reduced to nitrocellulose, but not much else. Of course I can't burn the nitrocellulose, because the Thorium Nitrate would decompose to it's nitrite and then to Thorium Dioxide, and I can't use Schweizer's reagent, because the Thorium Nitrate would just dissolve into it. Anyway, I boiled the water off (me being stupid and ignorant I forgot to use distilled water) and ended up getting a somewhat radioactive residue on the bottom of the saucepan I was using. I'm going to scrape this off, see how much I get and measure its' activity.

[sslaptnhablhat]

I've scraped off the majority of a brown, rubbery residue, and it measures about 150cpm, indicating there's barely any Thorium in it. Still going in my collection though.

[Arkcon]

because the Thorium Nitrate would decompose to it's nitrite and then to Thorium Dioxide,

And you're sure that doesn't already happen when the mantle is baked, or during its first firing.

and I can't use Schweizer's reagent, because the Thorium Nitrate would just dissolve into it.

Does it.  Also, if you've dissolved the mantle, you could get better yield with components no longer intimately mixed.

[sslaptnhablhat]

Schweizer's reagent is water-based and dissolves cellulose, and Th(NO₃)₄ is water-soluble, so that's out of the question for now. I've just left the gas mantle in some distilled water for almost 2 months, letting the water slowly evaporate, and it's down from 250ml to roughly 40ml, and it's pretty cloudy. I'm not sure what I'm going to do next.

[sslaptnhablhat]

Apparently "deionized water" is actually marked-up tap water, and the gas mantle is only a little less active than before, so instead I think I'll just burn it with a blowtorch and extract the ThO₂ some way.
What's up with these six downvotes I suddenly accumulated in the past week? What did I do wrong?

[Enthalpy]

Honest deionized water is just what it claims to be: its ions were removed. For instance its resistivity is much bigger than tap water's one.

I find a little bit sad to destroy the mantle from a historic lamp. Thorium ore is common. A practical alternative maybe?

No idea why you got the negs, but you get a pos from me as a consolation. Cheers!

[sslaptnhablhat]

Honest deionized water is just what it claims to be: its ions were removed. For instance its resistivity is much bigger than tap water's one.

Grrr, the Tesco employee I asked said it was distilled water. Honest mistake on their part though. I'm not too bothered either, they sell it for pennies on Ebay and I can make my own easily. Thanks for the info.

I find a little bit sad to destroy the mantle from a historic lamp. Thorium ore is common. A practical alternative maybe?

By old I meant from the '80s or '90s, I'm not certain on the date but it looks moreorless exactly like modern ones. Also I recently found out some manufacturers still produce Thoriated mantles.

No idea why you got the negs, but you get a pos from me as a consolation. Cheers!

Thanks! 

[Enthalpy]

Tungsten electrodes for welding contain several % thorium. Search "thorium" on eBay. Then, you have to separate the metals somehow.

Distilled vs deionized: the processes differ, the kind of residual impurities too, and for most uses both are good enough by far.

[sslaptnhablhat]

Tungsten electrodes for welding contain several % thorium. Search "thorium" on eBay. Then, you have to separate the metals somehow.

Red (2%) and orange (4%)-tipped TIG welding electrodes contain the respective amounts of Thorium Dioxide, and unlike with gas mantles, the final product won't have any rare-earth contamination that will be extremely difficult to separate. The downsides are it requires relatively concentrated H₂O₂, takes a lot of time, and you end up with relatively inert, very insoluble Thorium Dioxide, which I'm yet to find a way to synthesise ThOH (precursor to Th(NO₃)₄) from.

Overall, it's probably a great deal more efficient to extract Thorium from welding electrodes than it is from gas mantles (or even ore), so I might attempt it later and post my results here. Coincidentally one of my dad's close friends is a TIG welder, so I might ask him if I can "borrow" a few of his red-tipped electrodes.

[wildfyr]

Perhaps you could thorium dioxide into a more pliable ion with piranha?