4-Stroke - 21-5-2024 at 14:13
So I saw this video (https://www.youtube.com/watch?v=UKFEbYdKdJg) about making ethylene gas. I did not find any other videos about making ethylene in any useful
quantities. Here are my questions:
1. Is there any formula/chart to determine how big the tube/surface area of the aluminum oxide should be? (As it the minimum dimensions required to
convert say, 100g/h of alcohol vapor into ethylene.)
2. Is the sulfuric acid + ethanol method better? Because if the sulfuric acid can be regenerated, it would be a much better way as it is a lot faster
and just less hassle. Does anyone know the yields and the procedure for this method? Sorry, I couldn't find any except the one from the "War Gases"
book, and the yields/reaction duration are not specified.
3. I can't seem to find much information on ethylene gas at all. Are there are books/patents/SM threads that I should read?
Thanks in advance, and any help would be appreciated 
charley1957 - 21-5-2024 at 15:13
https://dacemirror.sci-hub.se/journal-article/69d90edebd841c...
Not sure if this will work or not.
The YouTube video shows that to be a piece of 1” pipe, looks to be about 16 inches long or so. He didn’t give any dimensions other than the 1”
pipe, so it doesn’t appear to be really critical. Try it, see what happens.
[Edited on May05-21-2024 by charley1957]
BromicAcid - 21-5-2024 at 15:19
When I first started getting into chemistry I made a batch of ether. I 'winged it' and just added sulfuric till it felt fine. Ended up making tons
of ethylene while would blow through my Graham condenser non-stop. No clue on how well it would work preparatively. What would you consider a useful
quantity? Are you planning on using liquid nitrogen to liquefy it?
bnull - 21-5-2024 at 17:29
(1) Sorry, no idea. I suspect that in your case it will be trial and error.
(2) See J. B. Cohen, Practical Organic Chemistry, Preparation 4 ("Ethylene Bromide"), p. 62. It is basically a mismanaged ether production. The setup below should be
good enough. You can recover sulfuric acid by decomposition of the sulfite or bisulfite in the wash bottles and oxidation of the sulfur dioxide
formed, maybe by absorption into hydrogen peroxide.
(3) The first useful links that appear when I search for "ethene from ethanol alumina" are: J. D. Butler, "Kinetics of the catalytic dehydration of ethanol over alumina"; S. P. Banzaraktsaeva, "Ethanol-to-ethylene dehydration on acid-modified ring-shaped alumina catalyst in a tubular reactor"; patent GB2049645A, "Activated alumina catalyst for the conversion of ethanol to ethylene". On the other hand, "dehydration of ethanol to ethylene"
gives: D. Fan, D.-J. Dai, H.-S.Wu, "Ethylene Formation by Catalytic Dehydration of Ethanol with Industrial Considerations"; M. Zhang, Y. Yu, "Dehydration of Ethanol to Ethylene"; BASF, "Ethanol to Ethylene (E2E)"; L. Ouayloul et al., "New mechanistic insights into the role of water in the dehydration of ethanol into ethylene over ZSM-5 catalysts at low
temperature".
By the way, be careful. Ethylene is also used as anaesthetic and you may feel a little funny if there is a leak nearby.
@BromicAcid: My first contact with ether involved accidentally setting my hand on fire. Good old times...