plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
Diaphragm cell (pictures)
I just started building a very crude prototype of diaphragm cell using polypropylene food container. I used an asbestos diaphragm supported by a
cheap iron sheet with drilled holes. A mesh would be better. One top and a bottom had an hole cut in them and they were soldered together. The cathode
is supported on the side of that. There is no catholyte in a diaphragm cell in general, the asbestos serving that purpose. See the pictures for more
details...
P.S: Sorry if the writing seams botched, as been 4 time I write for 20 min the posts and when I post it it does not post...
http://i1103.photobucket.com/albums/g469/plante1999/DSC00229...
http://i1103.photobucket.com/albums/g469/plante1999/DSC00234...
http://i1103.photobucket.com/albums/g469/plante1999/DSC00235...
http://i1103.photobucket.com/albums/g469/plante1999/DSC00238...
http://i1103.photobucket.com/albums/g469/plante1999/DSC00241...
http://i1103.photobucket.com/albums/g469/plante1999/DSC00244...
I never asked for this.
|
|
Paddywhacker
Hazard to Others
Posts: 478
Registered: 28-2-2009
Member Is Offline
Mood: No Mood
|
|
> P.S: Sorry if the writing seams botched, as been 4 time I write for 20 min the posts and when I post it it does not post...
Yeah, I've learned to highlight and copy my text on some boards so that I can repeat it with just a Ctrl-V if it fails.
Is that asbestos fiberboard? I haven't seen any of that for years.
It will be interesting to read how it works out. I would have thought that the iron, mesh, or any conductor, would polarise with one side an anode
and the other side a cathode.
[Edited on 18-12-2013 by Paddywhacker]
|
|
plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
I think I will try that next time...
It is an asbestos fiber sheet, grandfather had a few sheet left which he gave me long ago. The anode is in the top solution while the cathode is
directly on contact with the asbestos. The NaOH drip from the cathode to the bottom container.
Here is a rough idea of the cell.
[Edited on 18-12-2013 by plante1999]
I never asked for this.
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Is this to illustrate/investigate the general principle of a diaphragm cell or for actual production of lye solution? What power source are you using?
|
|
plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
Simply investigating, as if I build one for use it will be made with soldered plastic for cleanness and precision, maybe acrylic to make the design
perfect and another plastic for the lasting one.
I never asked for this.
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
And the power source?
|
|
plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
My usual 1940-1970 erra 3-7 V variable power supply made of 1/4 al plate. Rated 10 amps.
We see it well there:
http://i1103.photobucket.com/albums/g469/plante1999/009-1.jp...
I never asked for this.
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
It'll be interesting to hear what concentration of NaOH you can reach and what kind of problems you will (inevitably) encounter.
|
|
plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
In industry, the concentration is said to be 15%. That is mostly why the mercury process was mostly used at the time the membrane process was not yet
commercialized.
I never asked for this.
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
The real 'fun' is to get solid lye from that!
|
|
macckone
Dispenser of practical lab wisdom
Posts: 2168
Registered: 1-3-2013
Location: Over a mile high
Member Is Offline
Mood: Electrical
|
|
Interesting design.
what flow rate is the pump?
And how are you processing
the hydroxide solution?
|
|
testimento
Hazard to Others
Posts: 351
Registered: 10-6-2013
Member Is Offline
Mood: No Mood
|
|
This is very interesting!
Could the asbestos be replaced with something else, like modern syntetic ceramics?
This idea might sound very stupid and amateurish, but would micropore tape work? This could be literally taped onto a glass wool or similar thin
material and placed onto cathode plate as in pic.
What about gore-tex membrane?
[Edited on 9-2-2014 by testimento]
|
|
macckone
Dispenser of practical lab wisdom
Posts: 2168
Registered: 1-3-2013
Location: Over a mile high
Member Is Offline
Mood: Electrical
|
|
Quote: Originally posted by testimento | This is very interesting!
Could the asbestos be replaced with something else, like modern syntetic ceramics?
This idea might sound very stupid and amateurish, but would micropore tape work? This could be literally taped onto a glass wool or similar thin
material and placed onto cathode plate as in pic.
What about gore-tex membrane?
[Edited on 9-2-2014 by testimento] |
Anything that won't dissolve or be otherwise damaged in 15% NaOH and will provide sufficient resistance to flow should work as a diaphragm.
Some HEPA vacuum cleaner bags are made of polypropylene and
have a very small pore size. I would think several layers of that
might do the job. I know they work for filtering.
|
|