Sciencemadness Discussion Board

antimony trisulfide synthesis with ammonium thiocyanate and potassium antimony tartrate

ManyInterests - 23-3-2023 at 22:19

I've been meaning to make priming mixtures for firearm primers for a while, and I think the time has come that I start to make some basic reagents for the tasks.

I know that antimony trisulfide is an essential fuel in making priming mixtures and I looked at various ways that it can be made. PoorMansChemist has several videos on how he made some, and I would like some documentation if possible on its synthesis. Here is the video in question:

https://youtu.be/wE_ebGPvyYE

So in the 2nd half of the video after he tries the first method (union of the elements) he boils potassium antimony tartrate and ammonium thiocyanate together until it forms antimony trisulfide which is then filtered away. It seems simple enough, but PMC doesn't say how much ammonium thiocyanate he used (other than a comment that he had to add an additional 15-20 grams of sodium thiocyanate to the mixture). He does have another video where he bubbles hydrogen sulfide into an antimony chloride solution, but I am not interested in doing that method currently.

I've tried to search for documentation on how he made that, but it was to no avail. I also looked on this forum but found little about it, so I am making this thread. In my typical autistic manner, I will list my questions in list form.

1: Does anyone have any documentation on their production in a home lab?

2: Any idea on the proportions needed for the reaction to occur correctly? I am referring directly to the video that PMC made. I actually asked him directly on discord, but he isn't replying.

3: In terms of dangerous gasses produced. What kind of gasses would be released? I have a good gasmask that is rated for hydrogen cyanide if needed, but it is good to know what I would be dealing with (I will be reacting it on my balcony and watching through a glass window).

4: The leftover liquid after filteration. Any idea on what it might be and how to safely dispose of it? PMC just recommended putting it an old plastic bottle and throwing it in the trash. I would rather be a bit more responsible than that.

5: In terms of the antimony trisulfide itself. Is it hygroscopic? What are the appropriate measures for safely storing it for later use? Can I simply put it a plastic tupperware after it dries? Can it explode? I am thinking not as it is not explosive antimony, but any concern of friction or impact that I need to worry about?

Thanks for all the help

Herr Haber - 24-3-2023 at 20:34

I never attempted the synthesis, SbS3 is pretty easy to find so I cant help with 1 through 4
But 5 is easy. It's not hygroscopic and poses no more dangers than other "tame" fuels such as charcoal or sulfur in storage.
Regarding the sensitivity to friction, well, it is used as a solid lubricant so I wouldnt worry too much about that part :D

My experiments were limited to very small batches and were "just out of curiosity" seeing that it was used in some old pyrotechnic compositions.
Maybe I'm wrong about that part but if memory serves Shimizu mentions it a lot more than Conklin.

Some "tame" fuels (benzoates, ascorbic acid) that are not that impressive on their own can behave explosively in mixtures so be careful.

ManyInterests - 24-3-2023 at 22:06

Quote: Originally posted by Herr Haber  
I never attempted the synthesis, SbS3 is pretty easy to find so I cant help with 1 through 4
But 5 is easy. It's not hygroscopic and poses no more dangers than other "tame" fuels such as charcoal or sulfur in storage.
Regarding the sensitivity to friction, well, it is used as a solid lubricant so I wouldnt worry too much about that part :D

My experiments were limited to very small batches and were "just out of curiosity" seeing that it was used in some old pyrotechnic compositions.
Maybe I'm wrong about that part but if memory serves Shimizu mentions it a lot more than Conklin.

Some "tame" fuels (benzoates, ascorbic acid) that are not that impressive on their own can behave explosively in mixtures so be careful.


Thanks for that. Pyrotechnic materials are rather difficult to obtain in Canada, and while I did find a seller who sells to individuals, the prices are insane. For a 100 gram of 325 mesh antimony trisulfide the price was 175 USD. It is quite expensive at least from that seller.

If you know any Canadian sellers willing to sell to individuals for a more reasonable price I would be quite happy. It will mean I will have to sit on my ammonium thiocyanate supply (which will be my only supply for a good long time) but I am sure I will find some use for it in the future.

I will look up Shimizu. I did get Conklin's book, but the book is about pyrotechnic compositions and they don't mention how to make them. Obviously the compositions and the science behind them are quite fascinating, but I need to know how to make them, or at least obtain them, before I can do anything.

Since I have fairly limited information on the reagent quantities other than 'an excess' of thiocyanate was used. I will need to eyeball the quantities used in PMC's video. I hate to do things this way since I prefer to have more information than that. I guess this is one moment where I need to embrace the spirit of experimentation. I will need to approach with caution since this will be releasing toxic gasses that I am not familiar with! :D

sceptic - 26-3-2023 at 02:13

I found one other reference on this forum to a process similar to the one you mentioned. Have you seen this thread about making antimony sulfide?

Herr Haber - 26-3-2023 at 11:04

175 USD for 100 grams ?! That's robbery and a pretty good reason to be looking into the synthesis !
Pyrogarage.pl is far from Canada but you'd get 10kg for that money. Skylighter (US) may be a good alternative ? I dont know if they ship to Canada though.

What do you mean by "the book is about pyrotechnic compositions and they don't mention how to make them" ?
It has a wide range of compositions, many listed as examples or exercises. Do you mean that those books dont tell you how to make the chemicals needed ?
That's not entirely true but yes, those books are more about the end result than the journey compared to other literature you've been reading lately ;)

ManyInterests - 26-3-2023 at 20:00

Quote: Originally posted by sceptic  
I found one other reference on this forum to a process similar to the one you mentioned. Have you seen this thread about making antimony sulfide?


Thank for the thread. The post you mention is antimony pentasulfide. I am looking to make trisulfide. The methods they're using involve the union of the elements with antimony metal (which I have) sulfur (which I also have) and maybe other stuff. I am trying not to do something that involves crucibles right now.

I did ressurrect that thread to ask questions and draw attention to this thread.
Quote: Originally posted by Herr Haber  
175 USD for 100 grams ?! That's robbery and a pretty good reason to be looking into the synthesis !
Pyrogarage.pl is far from Canada but you'd get 10kg for that money. Skylighter (US) may be a good alternative ? I dont know if they ship to Canada though.

What do you mean by "the book is about pyrotechnic compositions and they don't mention how to make them" ?
It has a wide range of compositions, many listed as examples or exercises. Do you mean that those books dont tell you how to make the chemicals needed ?
That's not entirely true but yes, those books are more about the end result than the journey compared to other literature you've been reading lately ;)


Given that antimony trisulfide is not considered a chemical of concern in Canada, I wonder if pyrogarage would ship. I did buy pentaerythritol from a seller on Ebay and they shipped the chemicals with a 'photo developer kit' label to avoid customs. I wonder if pyrogarage does the same to avoid hassle. I will send them an email.

That being said, I feel kinda silly but... I realize I need to do a stoichiometry calculation! I just need the right formula to punch in and I see how much potassium antimony tartrate I need as well as the ammonium thiocyanate.

Edit: Pyrogarage doesn't appear to ship to Canada, sadly. They're strictly EU. Neither does Skylighter, they only ship to US locations.

[Edited on 27-3-2023 by ManyInterests]

[Edited on 27-3-2023 by ManyInterests]

[Edited on 27-3-2023 by ManyInterests]

ManyInterests - 31-5-2023 at 22:11

Just to let everyone know. I did find a seller of antimony trisulfide in Europe that sells to Canadians. onyxmet.com

I got a good supply. Might even buy some more just in case they stop selling, but I think the 250 grams I got is going to be plenty for a while.

Herr Haber - 1-6-2023 at 14:37

Onyxmet is a great. I dont think that's something they'll run out of supply though :)

I'm surprised no one suggested them to you earlier. Tbh I think about them for super pure element samples more than chemicals.
They have some 5N metals !!