FAQ - D2O, electrolysis, deuterium gas, heavy water.

[Richard Hull]

I have decided to make a quick rinse on heavy water electrolysis to obtain deuterium, (D2), gas. Heavy water is a name given to water that is composed solely of deuterium, replacing the normal hydrogen or protium. - D2O instead of H2O. Sold commonly as "Deuterium Oxide".

For the chemistry and isotopically specific out there....... deuterium is normally given in the correct literature as 2H indicating two nucleons in hydrogen (neutron added to the defining proton).....Unortunately, I can't superscript here....The 2 in front of the H should be in superscripted notation just as the 2 in H2O should be subscripted.

As free in nature, deuterium exists in the diatomic state as does normal hydrogen, H2 or deuterium, 2H2. The "D" is just a simplification for deuterium and is often used rather than the more cumbersome "H" notations.

Deuterium Oxide = 2H2O = D2O = Heavy water

This is a necessarily long FAQ, but should answer most questions on this often touched upon subject.

It must be stated that I have never done this specific electrolysis, but a very few others in these forums have, and have had varying degrees of success in their fusion efforts. As such, I have given pointers to the work of others at the end of this reference.

The world is becoming a more dangerous place with roaming nutballs and terrorists as well as careless, litigious individuals thrown into the mix. Governments, corporations and others who can control access to " special materials" are quickly erecting roadblocks to the casual sale and purchase of pressurized, cylinders of pure deuterium gas.

Many here, especially the very young or non-business affiliated, are finding it difficult or impossible to purchase a cylinder of pure D2 gas. A common roadblock is no sales to private individuals. Some block the road with special government or corporate control forms that must be completed prior to sale. Others demand a large minimum purchase or require you to have a corporate tax or federal ID number. Mostly, however, if they hear a very young voice over the phone they are wary of sending an explosive gas to a minor. Another dead giveaway in internet inquiries that will certainly go unanswered are e-mails from "punkgameboy@aol", "lollygagger6@hotmail", etc.....Youth is on its own journey and business is on its separate, more serious, path. Their mindset...."We have never been sued or federally prosecuted for NOT selling deuterium to 13 year olds."

Electrolysis of D2O, (heavy water), is a natural idea to those set adrift in overcoming the above outlined purchasing hassle. We examine and expand on the pros and cons of this route.

Tanked Deuterium gas system..............

The advantage of purchasing tanked, pure D2 gas is obvious in that you are ready to rock and roll once you have purchased the required regulator and gas line control needle valve. The gas is both dry and pure. This route is relatively expensive for the very young as a 50 liter (STP - Standard Temperature and Pressure) cylinder of D2 gas is currently.... $124.00 for the gas, $95.00 for the cylinder (not returnable or reusable), plus $30.00 or more shipping for a total of $249.00.....This pricing is, as of this posting, correct. I have just purchased this, today as a third reserve tank for my fusor. (One never knows when it will all go away)

A regulator assembly made for hydrogen is a bit over $150.00 with adapters. A needle valve that is servicable, but not fancy, can be had for $50.00, new. Add another $50.00 for lines and fittings and your all up gas costs on tanked D2 is about $500.00. By locating regulators and valving on e-bay or surplus, the costs might be kept under $400.00

It must be stated that perhaps 95% of all fusioneers here go with the above route, fighting the often uphill and rather expensive process solely due to convenience and proven performance via positive results from others doing fusion.

Electrolysis of heavy water (D2O)..............

There are a number of advantages to D2O electrolysis that are also mixed in with pitfalls. (Thus, proving that nothing is easy in this biz)

The advantages are, vastly lower cost per derived liter of gas, and no need to purchase an expensive gas regulator. D2O is readily avaialble and easy to purchase as it is, effectively, just water. Currently, heavy water can be had for about $55.00 for 100cc, (100grams). Let's do some math.....

A mole of gas, any gas, occupies 22.4 liters of volume @ STP. A mole of D2O has a mass of 20 grams. (2H2 + 0 = 4 + 16 = 20)
With 100 grams of heavy water@ $55.00, a 100% electrolysis will yield 122 liters, STP of D2 gas! In cylinder form, this would cost over $500.00! Not bad!

There are many flys in this ointment, as alluded to earlier. First, you will never electrolyze all the heavy water and there will be "process" losses. One might expect to actually collect about 75-90 liters of gas in a decently constructed electrolysis and processing apparatus. Still, you are going to get more gas for $55.00 than another fellow will get spending $249.00 for a 50 liter tank of gas.

The D2 gas you collect at electrolysis at STP will be WET!.... (in the vacuum sense of the word.) It must be scrupulously dried prior to admission into the fusor vacuum environment. This is a major task and noted in the supplied refs below. A lot of brain power and effort has been expended here. Take heed from those who have plowed this ground already. Most electrolysis based fusion failures are due to wet D2 poisoning the fusion effort. In successful electrolysis projects, even slightly wet D2 will end up at least imposing limits on the amount of fusion done.

The process............

Electrolysis involves two electrodes placed in a very slighly basic or acidified D20 solution. Ideally, these electrodes are of platinum or some other non-reactive metal. These electrodes are connected to a low voltage source of DC electricity.

At controlled current levels, each electrode will produce bubbles of gas. The bubbles at the positive electrode are of pure oxygen and the bubbles at the negative electrode are of pure deuterium gas, D2.

The art comes in isolating the bubbles in columns such that only the bubbles from each electrode are trapped and displace the electrolyte from the tubes, creating a chamber of pure gas over each electrode composed of only its specific gas product. The oxygen can, of course, just be vented out of solution as it is of no interest to us.
Volumetrically, the deuterium will occupy twice the volume of the oxygen produced.

I recommend the use of a microscopic flake of pure sodium, (or preferably Lithium), to be placed in the D2O to be electrolyzed. This will form NaOD and turn the D2O to a "basic" electrolye. Others have used differing acids or bases, but my suggested method keeps only D ions in solution as possible gaseous components. Again, read how others have done it... see below URLs.

Drying is the big fly in the ointment as electrolysis is easy. The resultant gas in the D2 column must be released into a dryer of some sort. This dryer must be both efficient and simple to impliment. Its output product must be totally isolated, once dried, in a separate vessel and all of it will be at or just below STP. All that is needed is a simple needle valve in a line to your fusor to admit your dried D2.

I have not delved into the mechanics of the process as this is a personal design effort and is "left as an exercise to the student". You will need to use the URLs below to see how others have assembled their apparatus and overcome some of the obstacles. There are other threads than those supplied; search them out.

Good luck should you choose this path. Please report in the forums on your successes and failures as both are instructive.

If others have a useful tell all URL specific to deuterium electrolysis, please let me know and I will include it in the body of this FAQ. I fear I have not got them all.

I have appended a simple schematic of a proposed D2 gas electrolyzer along with how it is used.

Richard Hull

Past useful postings.........

viewtopic.php?f=24&t=2526&hilit=electrolysis#p12036
view.php?bn=fusor_construction&thread=1 ... lysis&st=0
viewtopic.php?f=6&t=3005&hilit=heavy+water#p12515

[Rich Feldman]

Richard Hull wrote:
>> ... Currently heavy water can be had for about $55.00 for 100cc, (100grams). Let's do some math...
Nice treatise, Richard, as usual.
But please remind us why it's called "heavy" water.

[edit]here's a cool demo, in fact ice cold
http://jce.divched.org/jcesoft/cca/cca2 ... cube/8.htm
at a cost of about $15 according to Richard's price datum.