Sciencemadness Discussion Board

D2O Production

ScienceHideout - 30-9-2011 at 14:58

I have heard that you can produce deuterium oxide by electrolyzing water, or a dilute NaOH solution. Is this true? How can I go about doing such a procedure? Does anyone have any tips?

Also, is there anyone else wanting to make D2O besides me?

bob800 - 30-9-2011 at 15:13

I have had a similar idea, but it was immediately crushed when I learned that 7000 atoms of normal hydrogen contains only 1 atom of the deuterium isotope (from periodicvideos). I think this would be a far too massive project for the amateur.

If you really want some D<sub>2</sub>O, you can get some from United Nuclear: http://unitednuclear.com/index.php?main_page=product_info&am....

ScienceHideout - 30-9-2011 at 15:19

Yeah... 9 mL for $1.10 a mL.

ldanielrosa - 30-9-2011 at 23:48

If you can do this competitively with $1.10 per, please let us know how it comes out. I didn't run the numbers properly but with the overpotential, side reactions, power supply losses and other issues you may be looking at 100+ kWh for the 63 liters of water you need to electrolyze for the 9mL of product. It sure sounds like fun though.

I'm not sure what I'd do with 79,000 liters of hydrogen gas...


IrC - 1-10-2011 at 03:45

Hold the water at 1 or 2 degrees C, siphon the water trying to freeze. Use that in your cell. This would greatly lower the volume of water needing all those kilowatt hours and reduce the H2 produced for a given volume of D2O desired. Light water freezes at 0 C, heavy at 3.82 C. Or do the inverse process since D2O boils at 101.4 C instead of the 100 C for light water. Bottom line is you can greatly concentrate the D2O percentage using methods much more energy efficient before resorting to electrolysis. Or siphon the lower layer after standing for a while especially if you cool it enough to reduce thermal agitation. Density at STP (g/mL): 1.1056 (D2O), 0.9982 (H2O). Energy cost can be reduced further by using nature, cold in winter or heat in summer. Only makes sense to use your brain before running up the electric bill.


I should add:

http://en.wikipedia.org/wiki/Girdler_sulfide_process

http://en.wikipedia.org/wiki/Vacuum_distillation

http://en.wikipedia.org/wiki/Heavy_water


[Edited on 10-1-2011 by IrC]

Mildronate - 1-10-2011 at 13:00

ī have 500mL D2O but i do nothing with it. Why you whant make it?

IrC - 1-10-2011 at 14:53

Because He doesn't have 500 ml He does nothing with.

Mildronate - 2-10-2011 at 00:27

Cold fusion:)

What to do with heavy water

annaandherdad - 12-10-2011 at 10:21

Quote: Originally posted by Mildronate  
ī have 500mL D2O but i do nothing with it. Why you whant make it?


I'm planning to use 20gr D2O as a demo for my daughter's 3rd grade class. Got it from United Nuclear, cost about $20, which will be the cost of the demo.

What is the demo? Simple: Make 2 ice cubes, one with H2O, one with D20. Then put each in a glass of water. The heavy ice cube sinks.

Doesn't sound like much of a demo, does it? My plan is to let the kids set up the ice cube tray, place it on some dry ice to freeze while I explain what deuterium is, where it comes from (the big bang), it's role in energy production in stars, all of this with some visual aids on my Mac laptop. Then we get the frozen ice cubes and see which one floats.