Synthesis of Ethylene from Ethanol - Catalitic

Takui-jp,

I've been wondering about this one for a few hours, and I don't know if its a very feasable process since thermodynamically ethanol is more favorable than ethylene.

If you know something I don't, please share with the rest of the class; you have my interest at least.

Cool. An olefin is born , and the water vapor being generated won't build up since it is heavier and will go into the cooling bath. Very cool.

thanks man

i was actually looking for an industrial flowchart, you know, how to produce tons and tons of the product, but i guess it's an even harder job, i've googled it for hours last friday and couldn't find anything.

you think i could find it in a book or something

Hi takui-jp,

I found this book reference in the Merck Index:"Ethylene and its Industrial Derivatives" by S.A. Miller (1969, 1321pp). You could probably find it in a University Library that has ChemE programs.

You're probably not going to find it on the net. You said that this is for industrial preparation, so I'm assuming that you have some Chemistry or ChE background. That being said, why not think about how you would do it?

Start with the above lab prep and make sure it works. From there, and knowing how much is needed, start thinking about how to scale this up:

1. A vessel to hold the ethanol and heat it
2. Some type of cylinder/pipe to hold and heat the Alumina catalyst
3. A pump to transfer to ethanol vapor through the catalyst bed
4. A cooled separation vessel that contains water (I would use ethanol - unreacted ethanol will be collected and the ethene will still rise to the headspace)
5. A scrubber to remove any ethanol/byproduct vapors from the ethene
6. A compressor to fill cylinders with the ethene

This is fairly simplified, but you get the picture. This could be a batch or semi-continuous (you would have to stop to replace the catalyst from time to time) process.

Hope this helps!

Best Regards,

Mike

How would you control side reactions in scaling up?

I don't know! My post to takui-jp was meant to give general guidelines only - an example of a thought process. Maybe I wasn't very clear on that. I have not researched the possibility of side-reactions, let alone what they may be and under what conditions they might occur. In fact, the reaction may well be optimized at other than STP conditions. However, your question gives the original poster a good caveat (if he reads it).

A good and valid question. Thanks for the post!

Mike

Hi phoenix911,

If you mean catalyst beds, not really. My background is mainly batch processing of various reactions. I have done quite a bit of work with high-pressure hydrogenations (up to 100 bar/1500 psi). The catalyst in these (batch) reactions (Raney nickel, Raney cobalt, etc.), was mixed in with the reactants and, when the reaction was finished, filtered out of the product mixture.

My real job was to adapt our equipment to fit proposed reactions and to develop process procedures to ensure success for each product. Much of my focus was process control, hence my great interest in embedded microcontrollers, ADC, DAC serial communications as well as PID and fuzzy logic control schemes. I'm pretty much a geek, making my own circuit boards and circuits using (currently) PIC microcontrollers for various hobby applications. Keeps me pretty much out of trouble! (yeah right!).

Thanks for your comment.

Best Regards,

Mike