FAQ - Make your own deuterium from heavy water!! The video

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FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

Mark Rowley speaks as follows:

After being asked a few times over the past 18 months, I finally got around to making a very basic “how to” video regarding PEM Cell Deuterium.

IMPORTANT! Edit: Mark has created Three videos as of 5/12/21.............. R.H.

It is suggested that the videos on You tube listed below be watched in sequential order! The videos were actually created in reverse order and a second and third video were created by Mark to makeup for little understood aspects of his original video, (video #3), for the totally un-initiated in PEM cell ordering, set up, and operation. As such, many of the following replies and questions have been dealt with in the first two videos made as a response to issues raised in many of the following replies.

Video one below: What you receive when you order a PEM cell. These parts will be seen in the last two videos so pay attention. You get all you will need in the package. (except D2O and power)
Video two: This second video is crucial as it tells you how to get the PEM cell prep'd for use as well as key tips in the care, feeding and long term maintenance of your PEM cell.
Video three: The actual use of the PEM cell in making Deuterium from heavy water and connecting it to a fusor. (this was Mark's first and original video which forced the making of the first two videos at later dates).

View these videos in order

Video #1
Unboxing video for the reversible "horizon" PEM cell sold by Fuel Cell Earth.......
https://youtu.be/dGlxx4_Ov0g


Video#2
Loading the PEM cell, care and maintenance.....
https://www.youtube.com/watch?v=Vo22d5e-H10


Viedeo #3
This video primarily discusses the operational basics of the Horizon PEM Cell, the use of a 100ml syringe for collection, and hookup to a fusor.
As shown, it’s a performing arrangement which has allowed for decent neutron production without much complexity. It’s also not to be considered the only method but rather to provide the basics for any fusioneer to improve and expand upon.
https://youtu.be/hUxv6gB3SlA

Mark Rowley

With a bit of reorganized editing by R.H.
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

This isn't my FAQ!!! I did not want this post by Mark Rowley to just get buried in and amongst the thousands of old postings here in the Construction forum.

This is a marvelous FAQ due solely to the heroic work of Mark Rowley

This effort might best be called....."The Pem Cell- Making deuterium gas - The Movie"
A master piece of work by a selfless , "3 Star" Elite fusioneer and contributor. Mark Rowley

For those who cannot afford or obtain tanked deuterium gas for their fusor, this is a Godsend!

For and by Mark Rowley by the most pleased Richard Hull

All the posts that follow are my attempt to get Mark to make the two extra preamble videos found above. Following his adding two more videos I reorganized the original to make the original a true, follow-by-the numbers FAQ. The commentary below is not critical and do not let it confuse you. Only the suggested order of video watching above is where you need to concentrate if you would like an orderly exposition on the PEM cell.

However. do read deeper below as a lot of good follow-on tips are to be found on the many additional pages to be found in this FAQ
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Fusion is the energy of the future....and it always will be
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

Questions...........

For those of us who have never used a pem cell. You did not show how or where the D2O is used or loaded into the Pem cell. I am sure it is given in the Pem cell instructions. I assume it is preloaded into the cell in some fashion.

Assuming you load the cell, how many ml. of D2O is usually a needed to fill a cell

How many 100ml syringes will the full cell load, Typically

Richard Hull
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Thanks Richard. I’ll make a much shorter Part II showing how to fill and maintain the cell.

One full PEM cell is good for a little over three 100mL charges. One could probably get 4 but running the cell dry is a sure way to damage it.

Filling the cell is just a few drops. I’ll try to get a more accurate measurement in ml’s for the vid.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

I am sure part II will be every bit as good as part I. Post part II URL here as a reply when it is up. I can edit your text in the above initial post in this thread to include the new URL and any verbiage you wish added.

I have a couple of full tanks of D2 gas laid aside as a reserve from my last days at work in 2014. (Used my work as a business purchaser to get the D2 since 2000.)

The PEM cell has not be needed here. All of this and past posts have intrigued me regarding its use to obtain D2 for the fusor. You gave up another piece of advice I wasn't aware of in your reply above to my questions....."Don't let the cell run dry". Include all of this detailed user experience in part II. Your effort, much like the now famous Carl Willis videos on tuning up the 3He tube is invaluable to the person in dire need of a good monkey see-monkey do video.

If a picture is worth a thousand words, then a video made by an experienced user blasting out practical tips and warnings which are hard-won is worth ten thousand words.

Richard Hull
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Richard, here is Part II

https://youtu.be/Vo22d5e-H10

This video primarily discusses loading with heavy water and basic cell maintenance.

Specific to your questions, an empty cell requires 0.5mL to fill it. That charge is sufficient to fill three 100mL syringes with deuterium gas. It could probably fill four but it’d be dangerously close to running dry. I added all those details in Part II.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

Thanks for the new video, Mark and the details in your above response. I have edited the end of your original post to include this new video with a suggestion that it should be viewed first by folks with no idea of what this is all about. I hope this is OK with you.

Once again well done. This video cleared up a major issues for me in getting the cell ready to go. Which side you load, how to carefully load to avoid waste of D2O, and the important admonition of not running the cell dry...EVER! Another great tip you hit on related to long term storage of the cell EMPTY. These are things a person new to the PEM cell need to know in the care and feeding of the device prior to even thinking about using it as seen in the original video.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Jim Kovalchick »

Thanks to Mark and others, I am now making d gas out heavy water too. My fusor is very leaky but I managed a 15 minute run making enough neutrons to easily activate silver using 60 ml from a syringe. My chamber temperature was the only reason I stopped because I had another 60 ml in the syringe to use. I am using a 150 ml syringe because of my chamber size and leaks.
.
In some ways I Iike using the syringe instead of a lecture bottle because my bottle regulator has a control band that can move my current enough to require manual adjustments.
.
I can also reinforce the use of purging the syringe nipple that Mark did when first starting the fill and priming the line with d when first connecting to the fusor. I noticed the difference without. Without the prime, I found that my plasma first flashed at closer to air voltage and pressure for a few moments.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Jim,
I noticed your larger 150mL syringe (same as shown in Part 1) has an adapter that slides over the end of the syringe. Those did not come with my purchase of the same unit. Can you describe in detail how those work and did you get them separately?

Providing the seal is tight, this definitely opens the door to using the 150’s. Only change in filling procedures would be the need to purge a bit more contaminated D (~10mL?) out before filling.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Jim Kovalchick »

Mark,
Yes, the adapter comes with the syringe. It is made to fit the plastic tube that comes with it but works fine with the 2 mm tube that comes with the PEM cell. It presses onto the syringe nipple and doesn't seem to leak.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Jim Kovalchick »

Mark,
I also found that quickly capping the nipple on my fusor end helps eliminate the need to purge and prime between between syringe change outs.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Frank Sanns »

Nice videos Mark. Great explanations and walk throughs.

I keep thinking there must be a better and more voluminous way to store the D2. Maybe a bubbler into a glass or metal flask with a stopcock or valve. Bubble away until you have a liter then you don't have to PEM cell each time. The bubbler of course could not be full of water or even deuterated water. Mineral oil comes to mind. It is a common liquid used in bubblers where the off gasses cannot come in contact with water because.
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Thanks Frank

Making deuterium is almost of no consequence. Takes roughly 15 minutes for 100mL. I’ll start the PEM cell at the same time I begin heating up the diff pump. Everything readies up at about the same time. Not to mention all the other things to do before a fusion run, more often than not the gas is ready before I am.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Rex Allers »

I made this post yesterday in another thread. Richard asked me to repost it here and keep all the discussion in the FAQ, so...

Mark,
Congrats on your video. Not only on the content but also the production, very good video and audio.

----
I thought I'd post a bit of stuff here rather than in the FAQ version. My thought is, if there is any discussion here, the end results can be gleaned and used to update the FAQ. The goal is keeping as much chatty evolution out of the FAQ as possible.

-- So, 1st question. Mark, you mention that after a few uses your gas-holding syringe might stick a little as it fills, and how to deal with that. So I would expect the same could happen as it empties. Have you noticed any glitches in the flow rate into the chamber from stiction as the D2 is being pulled out?

-- Not directly related to producing D2, you have two valves in the path between the storage syringe and the chamber. You mention the metering valve closest to the chamber has fine control. You mention the other is a medium flow valve (my words, I didn't check the video). I'm curious if this medium flow valve plays much part in the metering of the D2 into the chamber or is it more of an on/off and the finer metering valve does all the real control?

You know how you use them and how they interact. I'm asking based on what I think I would expect. Just curious.

-- In your video, there seem to be long rods/knobs on the two valves. I presume these are just extensions that you added. No problem, just might help the viewer understand what they are seeing if there was a comment in any text footnotes to the video.

-- It might also help the full story to mention what the two valves are (Swagelok SS-SS4 or something). No need in the video, just follow-up in the post.

-- *Yes, my last three are not directly related to PEM D2 production. I don't intend these to be critical, I thought it just might fill out the usage story a bit.

---------------------------
In 2018 I posted a message in the New User Chat forum about using these small PEM cells. Here's the link (still surviving) --
viewtopic.php?f=46&t=12567

At the time Richard wanted me to move it to a FAQ post. I intended to do that. But first
I wanted to put together a small humidity sensor and measure the H (or D) output to see if a small humidity filter in-line was worth the effort. I never did those tests so I never posted to a FAQ.

So maybe I should still tweak up my old post a bit and make it into an additional FAQ.

Commentariate: Should I do that? If I do, should I put it into Mark's (via Richard) FAQ message or should I make it a separate FAQ and reference Mark's?

----
Now, two key differences in what my old post put together, vs. Mark's simple, straightforward usage.
I added two small chambers on the O2/water side made from small syringes (no plunger, just cut off cylinders as small reservoirs). See pics in my linked post.

The first of these two add-on tubes connects as closely as possible to the bottom nub on the O2/water side. The plan is to initially fill with water/D2O to a level equal to the top of the PEM membrane. The idea is to provide a small external reservoir so the liquid level on the membrane drops slower as the liquid is converted to gasses.

The second tube is connected to the top O2 output on the PEM cell. This O2 gas is allowed to just escape. In operation I noticed that the O2 bubbles in the cell were pumping a small amount of liquid out of this port as they escaped. The purpose of this second tube is just to provide a place to capture any expelled liquid and let it drain back into the PEM chamber.

I am welcome to any comments and especially about me posting my old message as a FAQ and also if my two external small cylindrical chambers are worth the effort.
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Hi Rex and thanks for the compliments.

Regarding the first question:
Yes, I have noticed the plunger slightly surge forward during fusor operation. However, the needle valves appear to regulate flow in a way where such movement has no effect. I have directly observed zero movement on the vacuum gauge and no noticeable change in neutron production or Star luminosity during those instances. From my experience, the only negative issue of the sticky syringe is during the filling process.

Second question:
Yes, two valves with one being a fine adjustment SS-SS4 needle valve followed by a medium flow valve, which is then followed by the syringe input tubing. Surprisingly, the medium flow valve is the main point of adjustment followed by the SS-SS4. Quite honestly, I could probably loose the SS-SS4 and suffer no significant issues with gas flow adjustment. Typically, the SS4 is opened about 3 turns and left alone. But again, as we know all fusor designs and assemblages are different. For PEM cell D2 I didn’t want to get too much into the specifics of my system other than the universal need for purging that valved feed line.

Third Question:
The extensions are just lexan rods I put in place to make it easier to adjust from a standing position.

Rex, I like your original PEM cell build. Having a more elaborate system to provide a constant flow is quite interesting. Something along those lines would be good for a larger chambered system where a 100mL syringe would be consumed rather quickly.

Regarding the humidity, I haven’t noticed anything Earth shattering. If you recall, I built a cold trap last year that had mixed results but leaned in the direction of some improved neutron count. I’m now somewhat skeptical of those results as it was only used on the older 2.75” cross fusor. After building the current and slightly larger system, I’ve since realized the 2.75” lacked stability. The new system being stable enough to walk away from is more suitable to testing the cold trap. I may revisit that arrangement and compare findings with this new system.

Overall, my main focus is simplification on all fronts. I understand comparatively complex PEM cell arrangements can be built but for an FAQ I think simple and basic is good. It offers an encouraging starting point for the newbie.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

This is all chatty stuff....But real stuff that totally belongs in this FAQ. I try to retrieve the best jewels like Mark's videos into the FAQs.

Chattiness in the FAQs by old boys with knowledge to contribute can be as chatty as they want. It must all be content based from knowledge or good questions from those out of their depths who have viewed all the videos and all the replies and still need answers. Only then should anyone ask a question or go chatty. I was totally amazed when Mark just plugged in the batteries in the original video?!?!! What? Where's the D2O? It was not covered at all! Thus I questioned. Mark went back to the video camera and did a first rate job of teaching how to prep the cell. I was made smarter for the question and now all others will be, too.

This FAQ Chatty? Yes! Valuable to the FAQ? Yes!

Rex, should you pull together a decent FAQ related to your work, it should be a separate FAQ. Keep me in the loop.

This and any FAQ can be as chatty as it needs to be as long as there is content of value, new experiences and better ideas.

Richard Hull
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

I want to make it plain what you get when you order the reversible fuel cell model FCSU-023 ($65.00)from Fuel Cell Earth on line. You can save $10.00 by ordering the electrolyzer only cell as noted above.

I heard in the video that stuff comes with the "kit" according to Mark Rowley.

To obtain the single cell on the website nothing is mentioned of a kit or what comes with it that I could see. They did offer kits of 5 cell educator kit and lots of kits with a cell a motor or a fan or a solar cell or any number of classroom and teaching kits. But not one mention of anything coming with the single cell purchase at $65. While I am not planning to turn the heavy water I have on hand into deuterium, I felt that one never knows what the future may bring, plus it seemed a cool thing to have. I figured I would just receive the cell and could scrounge the rest. I did look at their accessory page and you could buy all the cables, tubing and everything as extras. I did not want to pay their prices, so I just ordered the cell figuring I either already had most of the extras needed or could fashion what I needed.

Finally, these folks do not like the USPS. They must have a brother-in-law at FED EX or have a vast stock holding with FED EX. Using their cheapest offered shipping option from Massachusetts was $19.00!!

I was very pleased that their single cell offering comes as a ready to rock and roll "kit" which they do not offer as a kit in their on-line literature. So, don't buy the accessories!
I attach an image of what I received. Much of this is not made totally clear in the videos and definitely not in the literature. I felt that Mark must have purchased a kit from them as he does mention some of the stuff comes with the "kit". Anyway, here is what I received for my $65.00 +$19.00

The only thing you will need, as Mark points out is heavy water, and if for a fusor, a large 50-100ml syringe (see his video as the syringe is of a specific type.)

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Richard,
We’re definitely on the same page today. I woke up thinking I should post a picture of what a kit consists of. And low and behold I see your post! Perfect!

Yes, shipping charges are brutal. However, that brings me to a potential point of concern. 2-3 years ago, Horizon cells were marketed everywhere. eBay, Amazon, and a host of other websites marketing the product. Amazon was great as shipping cost was minimal if not “free”. However, about 18 months ago (pre covid) it all dried up. Almost appeared like the company was going out of business as you could not find them anywhere except through the place we’re now getting them.

I’m somewhat inclined to think the company is struggling or has moved on to different interests. Being as such, I’d recommend anyone who’s remotely thinking about generating their own deuterium to get one soon. If they don’t go out of business, good. But as a precaution, getting one now may be in ones best interest. And if you do, keep it sealed in the plastic pack until needed.

Last week I ordered one more for reserve.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Aidan_Roy »

There is also this website here, from horizon themselves, with a single cell price at $49 and $18 shipping for me. Not much but a little bit cheaper than what I saw Richard payed. I have yet to look at his source but seeing as I’m in Massachusetts it might be worth a peak. Hope this helps.

https://www.horizoneducational.com/pem- ... 173?v=1313
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Rex Allers »

Back near the begining of this FAQ thread Richard asked about the D2 volume from one cell charge. Mark replied,

"One full PEM cell is good for a little over three 100mL charges. One could probably get 4 but running the cell dry is a sure way to damage it."

Tonight I thought I'd try to do some calculations, and they came out to support that observation. Nice when that happens.

First, I wanted to measure, fairly accurately, the volume to fill my Horizon electrolyzer cell.

I have a 1 ml syringe.
1 ml syringe.jpg
I filled the syringe to the 1 ml mark, pusing out any air bubbles all the way through the tubing that would attach to the bottom cell nub. I slowly pushed the liquid into the cell
and when it filled to the top, the syringe read right at .6 ml. So:

0.4 ml to fill the cell.

In the calculation section that follows, the constants at the top came from the "CRC Handbook of Chemistry and Physics".

I think I got it right. Let me know if I messed anything up.

===================================
Any gas volume
24.47 liter/mole (@ STP)

Atomic Weights:
----------------
D, 2.014
O, 15.995

D2 mole = 4.028 g
O mole = 15.995 g
D2O mole = 20.023 g
------------------
D2O density = 1.105 g/ml
------------------

1 ml D2O = 1.105 g
= 1.105 / 20.023 = .05519 mol
= .05519 * 24470 = 1350.5 ml of D2

-----------------
My measurement of liquid volume to fill chamber of
Horizon electrolyzer cell is:
0.4 ml

We don't want to run it dry, so say we only consume
2/3 of that volume. That is about:
0.26 ml

So D2 electrolyzed would be:
1351 * 0.26 = 351 ml
of D2 generated.

Using all the D20 in the cell would yield
1351 * 0.4 = 540 ml
of D2

========
Here's another calc. I bought a bottle with 100g of D2O

100g / 20.023 = 4.994 mol
4.994 * 24.47 = 122 L of D2 for the bottle
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Richard Hull »

We ran these calcs way back. We determined you get a lot more D2 via electrolyzation per unit dollar spent than tanked gas. A 50 liter tank can cost over $350 now with about $100 being the disposable, non-refillable tank. So in a large tank 100 liters might cost $500 in bulk. This is opposed to about $80-100 for D2O with similar gas capability and a lot of electrolyzation passes. The sole advantage to the tanked gas is you avoid a bit of a hassle every time you want to do fusion and have to be very mindful of not running out of D2 at a critical moment of operation. Obtaining some of those larger capacity storage cells for the electrolyzer would help obviate this though. I note Mark's process seems to warrant only pure D2 gets into his fusor. This is very important and demands evacuation of the lines which require a bit of forethought in construction design if you plan on getting your gas this way. This isn't present with tanked gas as you are constantly connecting and disconnecting you gas bottle, (syringe) if you electrolyze.

Mark seemed to do OK for his runs with just a 100ml syringe once he got his operation down to a routine.

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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Jim Kovalchick »

I have been using a 150 ml syringe, but I usually fill to 120. I have found that with my leaky 6 inch tee chamber running at 0.01 mbarr, and around 40 kV and 10 mA, I use about 60 ml before my chamber gets too hot to keep neutron numbers from falling. This is usually 15 minutes.

With regard to shuttling syringes and the resulting need vent and purge, I will be adding fittings and clamp valves to eliminate the need to separate the tubing.
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Frank Sanns »

Anybody know how the Hydrofill PEM unit gets the pressure in the Hydrostick canisters up to 400 psi? Whatever THAT is would solve all the problems for a reasonable compact storage reservoir.
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Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Mark Rowley »

Frank, hopefully Andrew Seltzman sees this post. After all the work he’s done on the little cylinders I’m fairly sure he has the answer.

Regarding the need for such a big reservoir I think we should ask ourselves a few questions…

How many folks build neutron capable fusors that go anything beyond “the big win”?

Out of that tiny fraction that do, how many get their systems efficient enough to begin activation work?

Out that smaller fraction, how many people add the necessary cooling to keep “activation capable” neutron output sustainable past 20-30 minutes?

In reality, we’re only talking about the rarest of rare occurrences. Being as such, it appears there are only three situations where a large reservoir would be needed:

1) a fusor capable of very long operational periods

2) a fledgling fusor builder who is still learning the ropes of gas handling and throttle efficiency. With certainty, I can say I wasted quite a bit of gas when I was getting my system off the ground. However, if I had a big reservoir, maybe I wouldn’t have focused as much as I have on gas use efficiency. Regarding that phase of learning, the occasional re-filling of the syringe was of no consequence.

3) a large chambered fusor

As discussed before, most if not all Fusors are as unique as a fingerprint. Gas effeciency will greatly depend on chamber size and the type of secondary pumping system one uses (not to mention smaller factors like needle valve types and such).

As long as ones system is small (cube fusor, 2.75” type, my cylinder system, etc) and cooled, making a 100mL syringe last a full hour at the mega n/s mark is attainable. As of now the best I’ve done is a bit over 45 minutes. My only limitation was a psu issue several months ago which has since been fixed. There was more than enough gas left in the syringe to take it home.

My main point of all this is of course directed to the newbies and rookies. For them, a PEM cell and syringe is all they need. It’s important to highlight, especially in a FAQ which is mostly frequented by the new folks.

Mark Rowley
Frank Sanns
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Real name: Frank Sanns

Re: FAQ - Make your own deuterium from heavy water!! The video

Post by Frank Sanns »

My chamber is one of the larger ones at over 22 liters. As such, outgassing is a big issue so it takes gas. Normally I run a heavy deuterium stream to keep the chamber flushed of any outgassing. The ruddy color disappears in an hour or so with a good deuterium stream. That is for those of us that are not running everyday or like me, opening it up often to run different geometries and shell configurations. .

The large chamber has way more surface area to dissipate the heat. So a big chamber is good and a big chamber is bad. Still, in 20 years, I am only on my second cylinder. In my area, cylinders are hard to come by to purchase. The local dealers want you to pay a monthly leasing fee. No go for me as it takes me a long time to use a bottle. Some out of state suppliers will sell then there is the hazardous shipping charges.

I have a couple of PEM cells and have wanted to use the deuterium from them as the flush gas and the gas to bring it up to higher pressure between runs. I just don't want to dawdle with it every time I want to flush. It would be great to get enough to be able to sparge with no mind to how much is being used. I may just run my high vacuum pump and pull down a container and back fill it with electrolyzed D2. Running at some pressure would be a win. Hopefully Andrew can shed light.

For the new people, more gas makes getting to neutrons a little faster, especially in a less refined chamber or with little experience.

Just some thoughts from another angle.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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