(Newbee)
05-17-02 09:32
No 309841
(Rated as: excellent)
Hi there,
i hope its interesting for you guys, Merck GmbH has something called Sulfidogen. When its heated it generates H2S. Here is the way to make it yourself:
A porcelain pot with Paraffin is heated in a waterbath. When its molten sulfur is added and the stuff is stirred until it gets homogeneous. Then "Kieselgur" (diatomaceous earth/das Kieselgur i dont know the correct translation) is added. First the mixture appears "grießartig". After some more minutes stirring and heating it gets viscous. then you can stop heating and let it cool down. it geta an yellow/Gray pasta at 30-40°C its gooey. at 20°C it is a hard prudish stuff. you can heat it a bit (to 40°C) an form small balls of it, with a wight of 0,5g. 0,5g of it heated to 170°C will produce 120mg H2S so it is easy to calculate the needed ammount. The gas is anhydous and do not need any futher cleaning.
Edit:
25 : 15 : 7
Paraffin : Sulfur : Kieselgur
Wattebausch = glasswool
Füllmasse aus paraffin Schwefelblüte = the above made substance
Thats it.
Got that from:
Jander / Blasius Preperative Anorganische chemie.
If anyone want the scanned pictures pm me.
as i think the "Kipp" apparature is used by most of people here i dont post the pic/ref. it uses HCl+FeS = H2S then cleaned through H2O and H2SO4. But i think that is well documented.
Edit:
here are the original scanned pages:
http://www.geocities.com/waaaaxity/Bild2
http://www.geocities.com/waaaaxity/Bild1
http://www.geocities.com/waaaaxity/Bild3
(Hive Addict)
05-17-02 20:50
No 310034
Thanks for this, I've been looking for more information on this method of producing H2S.
As far as I know the parafin wax can be white candle wax, and the Kieselgur is commonly known as Fullers Earth (Nobel used it to absorb nitroglycerine to make dynamite).
(watch out for FMAN
)Don't cry for me I'm the cleaner
(Hive Addict)
05-17-02 23:36
No 310075
Sorry , I may have been jumping the gun on my last post .
Does the artical refer to parafin wax or parafin oil ?
Don't cry for me I'm the cleaner
(Chief Bee)
05-17-02 23:40
No 310077
Paraffin wax. The first step in the preparation is to melt it.
(Stranger)
05-18-02 01:08
No 310126
The gas is anhydous and do not need any futher cleaning.
Hmm, that kind of H2S generator is used a lot in anorganic analytic (the qualitative kind). But as I can remember, yes, the gas is dry, but there are always some by-products from crack-reactions, formed by the paraffin. The glass wool won't stop contamination of your reaction mixture by these crack-products, especially if your intention goes to larger batches (H2S for HI production comes to mind). To avoid this we always used some kind of gas trap, for example a wash bottle immersed in ice-water - worked fine and there was no contamination of the reaction mix (can be seen as an oily layer on top).
Quidquid agis, prudenter agas et respice finem!