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The Bucket Cell - Start to Finish


Swede

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I added a simple gadget to the bucket cell that's worth sharing, I think. A couple of the common tasks when doing a run is to visually verify the liquid level in your cell if the cell is opaque, and also obtain a sample of the electrolyte for analysis, like pH and chloride. Here is a simple and elegant way to do it.

 

I added a small PVC bulkhead fitting to the lid, which I drilled out to 1/4". Next, I took an old 1ml pipette - any glass tube would do fine - and cut off the skinny tip and flame-polished the end. Near the top, I added a little viton o-ring that fits snugly. This goes into the PVC bulkhead.

 

http://www.5bears.com/s2f/s2f048.jpg

 

 

To use, it, simply place your finger over the end of the pipette, and withdraw it. Set it next to the bucket at the appropriate level, and note where the liquid is in the pipette. I plan on using a marker to calibrate the bucket, with the level of the electrode tops clearly marked. The object obviously is to keep the liquid level where it needs to be. And if you need a sample of electrolyte, simply drain the pipette into a sample cup.

 

http://www.5bears.com/s2f/s2f051.jpg

 

While all this is going on, I've been calibrating my drip system. I re-checked the hospital IV regulator devices, and found that the printed flow rate, like 150 ml/hour, simply isn't accurate enough to rely on, because it varies wildly with head pressure - a higher system means higher flow rates. So the way to go with a drip system is to definitely have a transparent drop chamber, where you can count the drops per minute. Knowing that 12 (or 20, whatever) drops = 1 ml, then the flow rate is easy to calibrate.

 

I've got a trip tomorrow that will take me out of town tomorrow, 27 Sep. I hope to have this thing under power next week early.

I like the idea for the pipette to check the level of the liquor, ph, chloride ext. If I understand correctly it acts like a thief. Now a little tid-bit of advise for any one building a cell like this(correct me if i am wrong) but a better way to do this would have been to put a bulkhead fitting on the side of the bucket below the level of the electrodes. Then I would run a 90 degree angle PVC fitting from the bulkhead fitting to a PVC T connecter. From there I would attach PVC ball valve to the side of you T connecter that faces away from the bucket ( to to take samples of your liquor). On the top of the T connector I would attach a rubber grommet. In that rubber grommet would rest either your pipette or if you are lucky a burette. This would allow for active viewing of your liquor level and color. Also please remember to run your gases produced through water(to prevent flash backs, and to remove some chlorine). I mean no disrespect to anyone with any of my posts. I am talking from experience when I talk about any chlorate or perchlorate synthesis I have been doing them for 7 years 4 years for a government project, and 3 privately. I did not think what I said before was very complex, i under stand that this a guide to a crude synthesis of kclo4. for home electrolysis I had a 2.5 litter cell that i had hooked up to 4 arduino boards, to check and adjust almost ever thing, that is complex this is not. Hope this helped.edit: Something else I wanted to point out was that it take 25% less time approximately to start with kcl then nacl. so it is faster for the same about of finished kclo4 to start with kcl. Edited by pyroshell
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I like the idea for the pipette to check the level of the liquor, ph, chloride ext. If I understand correctly it acts like a thief. Now a little tid-bit of advise for any one building a cell like this(correct me if i am wrong) but a better way to do this would have been to put a bulkhead fitting on the side of the bucket below the level of the electrodes. Then I would run a 90 degree angle PVC fitting from the bulkhead fitting to a PVC T connecter. From there I would attach PVC ball valve to the side of you T connecter that faces away from the bucket ( to to take samples of your liquor). On the top of the T connector I would attach a rubber grommet. In that rubber grommet would rest either your pipette or if you are lucky a burette. This would allow for active viewing of your liquor level and color. Also please remember to run your gases produced through water(to prevent flash backs, and to remove some chlorine). I mean no disrespect to anyone with any of my posts. I am talking from experience when I talk about any chlorate or perchlorate synthesis I have been doing them for 7 years 4 years for a government project, and 3 privately. I did not think what I said before was very complex, i under stand that this a guide to a crude synthesis of kclo4. for home electrolysis I had a 2.5 litter cell that i had hooked up to 4 arduino boards, to check and adjust almost ever thing, that is complex this is not. Hope this helped.edit: Something else I wanted to point out was that it take 25% less time approximately to start with kcl then nacl. so it is faster for the same about of finished kclo4 to start with kcl.

 

Hi pyroshell,

 

If you go to and read Swede's blog, "You'll put your eye out...", in an attempt to see the fluid level in an opaque cell, he tried that. I suggest you read through and follow his experiences there (in his blogs) and you'll see our current thinking on the subject. I've read and reread it several times and can say I've benefited from his experience (we all have).

 

The fact that he's skilled at documenting his experiments and experiences, has made Swede's blogs an excellent reference and resource, and helps us all avoid pitfalls along the path. The blogs also open up to us other ways and options as to how we can approach the subject.

 

Read them thoroughly. I highly recommend them.

 

WSMcool2.gif

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Hear! Hear! I second that!

I do not like peaching about what WSM said, but it is true. I have found that those with the most questions are those who have not read all the information found in the pages of this forum. If one would just read then the persons own questions would more that likely be answered. Read all the pertaining topics in regards to chlorate and pre chlorate in this forum, Swede's blog as well and check the internet for some more information.

I do not know how many times I have said to do so about researching the subject more then ask question when something is not clear. Beleive me when I say that there will be someone here who will help you..............Pat

Edited by patsroom
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" I am talking from experience when I talk about any chlorate or perchlorate synthesis I have been doing them for 7 years 4 years for a government project, and 3 privately."

 

What government project have you been working on that makes chlorates and/or perchlorates in a bucket type cell (an amateur type cell)?

 

What anode material have you been using for making the perchlorate?

 

Frank

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Nice to see you posting again swede! Would love to get my hands on some KCl nuggets myself...

 

What part of the world do you live in? Knowing that would help us give useful suggestions...

 

WSMcool2.gif

Edited by WSM
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Hi pyroshell,

 

If you go to and read Swede's blog, "You'll put your eye out...", in an attempt to see the fluid level in an opaque cell, he tried that. I suggest you read through and follow his experiences there (in his blogs) and you'll see our current thinking on the subject. I've read and reread it several times and can say I've benefited from his experience (we all have).

 

The fact that he's skilled at documenting his experiments and experiences, has made Swede's blogs an excellent reference and resource, and helps us all avoid pitfalls along the path. The blogs also open up to us other ways and options as to how we can approach the subject.

 

Read them thoroughly. I highly recommend them.

 

WSMcool2.gif

Oh sorry I did not read his blog.(I did not know he had one) I do not me to spam or derail this thread. From now on I will read his blog bo fore i reply to this thread. I am very sorry about doing that.
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Just a note to all who are interested: Of the 34 replies now up to 35 replies I do beleive that there is only about 5 and 1/2 that pretains to this topic (the-bucke- cell-start-to-finish). Not that some of the other replies do not belong here, but I found that interesting.........2ohmy.gif .......Pat
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I am itching to read pyroshells accounts of making chlorate and perchlorate for 7 (seven) years, 4 years government project, 3 years private!

 

@ pyroshell : What anode did you use for the perchlorate?

 

A very easy and very visual way to put a level indicator on a bucket type cell is to get a rod (like a pipette) and put a float on the bottom end. The float and rod must be sealed (it must float). This is placed into the cell by taking the lid off and putting the rod up through the hole/flange in the lid. The liquid level can be seen at a glance by the amount the rod is protruding through the hole in the lid.

 

Frank

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I have no probs with guys tossing ideas out. This project went slowly over the weekend because of too much real work, but hopefully thursday, it'll see power.

 

I've tried all sorts of devices to take samples and monitor liquid level in an opaque cell, and when using potassium salts, every one of them failed. One was a permanent sight gauge using glass that worked great until the liquor was saturated with chlorate. When that happened, the cooler sight glass forced crystallization, and the tube jammed solid with chlorate and no longer worked.

 

Probably the dumbest thing I did was add a little ball valve to the bottom of my cell, thinking "This'll be an awesome and elegant drain for the electrolyte!" Of course, it too jammed solid, so solidly that I had to take a screw driver and a mallet and chip out the xtals from the valve.

 

http://www.5bears.com/perc/tc209.jpg

 

"No worky!" biggrin2.gif At one point, I had dual peristaltic pumps, multiple liquid manifolds, all sorts of cosmic ideas, and they all succumbed to xtal jamming. I knew there'd be solids, but I thought that they'd remain fine, and permit flow. Not so, at all. Of course, if the system was sodium, it'd all work like a champ, and the only reason I persist in potassium is because I am stubborn, and I dislike the notion of a displacement operation that pollutes the product with a mixture of cations.

 

Lot's of guys go the sodium route, and it works very well, so please don't ever let anything I prefer to drive one's own desires and instincts in this process. There's tons of room for experimentation! I do know that as the years have gone by, I'm leaning towards simplicity.

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I spent far too much time on pH probes today. Again, the idea behind the simple bucket cell is so one doesn't have to mess with pH probes and meters, but I still need to use them to verify it works without them. That makes no sense at all, does it? wink2.gif

 

I've always been a fan of Milwaukee pH stuff. They occupy a niche between school and aquarium junk, and expensive lab stuff. I have a MW-101 equivalent. Look for a meter with a manual temperature adjustment on front. Those with automatic temp compensation inside either require a special probe, or a separate temperature probe, and all of that is a pain. It's easier just to set it manually, because we generally know the temperature of the sample. Look for one with simple calibration procedures, because you'll have to recalibrate often, or it's all junk, because even the best probes drift.

 

For the (per)chlorate process, don't even bother with a pH pen or some junk from eBay. You've got to pay to play, and a decent setup will run at least $200 for meter and probe. You'll need two buffers for calibration - get the 7.0 and the 10.0, and get the big bottles. They are cheap, and you'll go through it fairly rapidly. The good news is, a nice pH meter can be used for a number of other lab processes. And if a pH meter is out of your price range, pH papers can be used with a bit of care and sneaky manipulation. But the best you'll probably be able to do is pH +/- 1.0 or so. And one last warning, NEVER buy a pH probe from eBay, even one new in box, because they have a shelf life. It might be like buying an alkaline battery with a use-by date of 2002. These things get thrown out all the time from labs, and guys going dumpster-diving get them free and then re-sell them.

 

A decent meter lasts forever, but probes never do. I have four probes. Two MA911 epoxy gel-filled probes, a higher end MA917, and a cheap aquarium probe off eBay. All had been stored correctly, with the tips immersed in 3M KCl. The two MA911 probes had served me very well, but they are at the end of their lives. You can tell when a probe is about dead when two things happen... the response is really slow, like 30 to 60 seconds, or it cannot be calibrated. My MA911 probes can still be calibrated, but they are a bit slow, so I opened up the NIB MA917.

 

This probe has a glass body, and is refillable with electrolyte! This makes me happy, because when it begins to sicken, I can replace the internal electrolyte, which is nothing more than 3.5M KCl. A good read on pH probes in general can be found here. I recommend a glass probe because I am hopeful that the toxic and harsh environment it will see, can be repaired with fresh electrolyte. We'll see.

 

Anyway, the $20 aquarium probe fell apart in my hands. Literally. It was a total waste of money, and even when new, it managed only a dozen pH readings. The gel-filled yellow MA911 probes have hung in there. Both of them calibrated OK, but were just very slow. The glass probe was like a Ferrari... very fast readings. But again, I haven't used it yet with chlorate.

 

To check cell sample pH readings, get a stack of plastic bathroom cups. Set up 4 in a row, Fill one with your sample, and three with distilled water. Remove your probe from its container, rinse in distilled cup one, then into the liquor. Count to 5, and if it's not settled yet, make your best guess, because if you leave it in there longer, it'll die sooner. Remember, at best, all we need is pH within 0.2 or so, so 6.6 or 6.8, they are all the same. Immediately rinse the probe in water cup one, then two, then three, then back into it's special storage container.

 

That was my exciting afternoon! I was glad to see the glass probe perform so well, because it had been sitting on a shelf since 2009 or so. I had prepared some ultra-pure 3.5M KCl just in case to refill it, but it turned out to not be necessary.

 

Tomorrow, I'll do a final set up and hopefully power-on.

Edited by Swede
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look for Solumop K2O. Works for sure and is cheap.

 

http://datasheets.k-plus-s.com/ehswww/da/e/result/openSingleRep_main_fs.jsp?P_LANGU=D&P_SYS=5&C001=PDB&C003=E&C005=K0004&C900=PDB-KALI4

 

Chemical Analysis: typical w

• Potassium chloride (KCl) 96.4 %

• Others (NaCl, MgCl 2 , K 2 SO 4 , MgSO 4 ,

CaSO 4 , etc.)

3.4 %

• Moisture 0.2 %

• H 2 O-Insolubles < 0.1 %

 

My knowledge in chemistry is rather not so good, but how about those sulfates in there? Is that a problem?

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I can see my float + glass tube working perfectly after it is set up.

Next day it is still working perfectly. Next day it appears to work perfectly.

Next day it has dissapeared by sinking to the bottom with K chlorate

crystals stuck to the float!

 

What substances would not allow K chlorate to stick to them. Teflon?

It would not be cheap or simply to start making critical parts of the

bucket system out of Teflon (assuming it is K chlorate phobic).

 

If you have to have parts of the system that will have no K chlorate

depositing on them then a small heater in that area might be the only

way to do it. Simplicity going out the the window.

 

Frank

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I can see my float + glass tube working perfectly after it is set up.

Next day it is still working perfectly. Next day it appears to work perfectly.

Next day it has dissapeared by sinking to the bottom with K chlorate

crystals stuck to the float!

What substances would not allow K chlorate to stick to them. Teflon?

It would not be cheap or simply to start making critical parts of the

bucket system out of Teflon (assuming it is K chlorate phobic).

If you have to have parts of the system that will have no K chlorate

depositing on them then a small heater in that area might be the only

way to do it. Simplicity going out the the window.

Frank

 

The simplest system I ever built involved a one gallon (3.785 liter) glass pickle jar with a 4" (~100mm) PVC pipe cap for a lid. It ended up working quite well, BUT it was too small for my grandiose plans to scale up and make a continuous system.

 

I've said it before, and repeat it here... It's amazing how quickly a simple idea can get complicated!!! 2blink.gif 2rolleyes.gif

 

WSMcool2.gif

Edited by WSM
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Frank, The chlorate crystals are tough little buggers, and since no cell is ever 100% thermally uniform, they form at the cool spots, wherever they are, and jam and stick like crazy. When I put that ball valve on my cell, I thought when I opened it, there'd be a whoosh of crystals in water, but nothing even close. I took the ball valve off and ran hot tap water on the mass... nothing. It looked like rock candy in there. I have to chisel it out.

 

I'd bet they'd not stick to PTFE, PFA, or FEP, but if it's inside a tube, like a teflon tube, I think they'd jam it up mechanically.

 

I spent most of the day making an HCl drip system. It turned out to be a bit harder than I thought. I used an empty 1 gallon poly jug that held 30% H2O2 originally, and what's nice is that it has a transparent window "strip" to see the liquid level. So I calibrated it with magic marker every 250 ml. Over a run, that should get me close to total volume delivered. I can always use before & after graduated cylinders to get more precise.

 

The hard part was a quality path for the acid. I replaced the cap with a big rubber bung that I drilled for a male luer lock fitting, allowing for easy tube swaps and such, From there, the path goes to a pinch stop valve, a needle valve (can be replaced with a cheap IV regulator valve), a drip count chamber,and from there, into the cell.

 

Head pressure drives the flow, so I need to do a calibration run when it's all set up. I'm going to hang the jug from a hook in a high spot, or simply use a high shelf.

 

I'm anticipating 60 amps. With 32% muriatic acid, that means the cell will need only 3.42 ml per hour. That is a REALLY slow drip rate. Dilution is the answer. I'm just taking a shot here, and I think at 60 amps, the cell is going to be fairly warm and the liquid loss is going to be about 20 ml per hour If the system evaporates 20 ml/hour, I'll have to calculate an appropriate dilution.

 

USA muriatic acid is about 31.5%, averages about 10.5M. Rather than messing with percentages any more, I'm going to shift to molarity, because it is easier to work with. Densities go away.

 

The 0.057ml conc acid per amp-hour becomes 0.0005985 moles HCl per amp-hour. Dilution of 10.5M acid to any molarity is easy. We need to determine evaporative and gas losses in a cell which is going to vary wildly from setup to setup, and will have to be approached individually. But if I know my cell is at 60 amps and I am losing 14 ml per hour, the math derives to a 2.5M HCl drip at 14 ml/h to exactly make up for evap losses. Yes I made charts, and yes I am a dork!

 

My chart has AMPERES as the X axis, volume demand in ml per hour as the Y, and a series of differing molarities across the field, all based upon the 0.0005985 moles of HCl per AH value. It can be approached from either axis or even whatever molarity of acid you want to use.

 

The math is simple. Let's say you want to know how much of a 3M HCl solution to deliver. Convert to milliliters...,

 

3M / 1000 = 0.003 moles per ml. 0.0005985 / 0.003 = 0.1995 ml per AH.

 

To prepare a particular molarity HCl, the simplest way in my mind is to think in terms of one liter. Let's say you want a 2.5M solution, and you're starting with 10.5M. Isolate 2.5 moles of HCl by pouring 2.5 / 10.5 or 0.238 liters (238 ml) of the conc. acid into another container. Dilute this to one liter. Your 2.5 Moles of HCl are now swimming around in one liter, 2.5M by definition.

 

So until I can figure out what the liquid losses are withthis thing, I'm going to have to wing it. I'm still going to add the correct HCl, but I just need to watch for overflow or too much electrolyte loss.

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http://datasheets.k-...&C900=PDB-KALI4

 

 

 

My knowledge in chemistry is rather not so good, but how about those sulfates in there? Is that a problem?

 

96+ % KCl... I'd say go for it. The rest is probably going to be soluble, meaning it shouldn't end up in your product so long as you give it a decent wash, which is always smart to do, regardless. The very nature of crystal formation precludes impurities. IOW, crystams tend to be pure and to kick out bad stuff. And we;re making oxidizer, not reagent stuff.

 

One way to do it - dissolve it in a big bucket. Let it sit overnight. Any insolubles should settle to the bottom. the decant (carefully pour off) the top part, leaving the last few % behind, assuming there's anything there to begin with after dissolving.

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  • 2 weeks later...

I've made progress with the BCA for my friend.

 

post-9734-0-97841300-1350791212_thumb.jpg post-9734-0-79026300-1350791204_thumb.jpg

 

As can be seen, I'm bolting the BCA to the lid with stainless steel screws that don't go through the clear PVC plate (so the hardware isn't exposed to the cell environment). The BCA has a flat Viton gasket (black in color) sandwiched between the PVC and the HDPE bucket lid to seal everything where the two materials meet. I still need to peel the protective plastic sheet off the PVC plate and populate the BCA with fittings for the electrodes, a vent, an acid injector, etc.

 

I've begun to build the electrodes. The anode is spot welded to the tubular lead but I still need to tap the end and fill it with solder. The cathodes (two) will "box" the anode, but I need to fabricate the pillars to fix the spacing plus weld the tubular lead to it (everything made of CP titanium, of course). I'll post more as I progress the job...

 

WSM B)

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I've made progress with the BCA for my friend.

As can be seen, I'm bolting the BCA to the lid with stainless steel screws that don't go through the clear PVC plate (so the hardware isn't exposed to the cell environment). The BCA has a flat Viton gasket (black in color) sandwiched between the PVC and the HDPE bucket lid to seal everything where the two materials meet. I still need to peel the protective plastic sheet off the PVC plate and populate the BCA with fittings for the electrodes, a vent, an acid injector, etc.

I've begun to build the electrodes. The anode is spot welded to the tubular lead but I still need to tap the end and fill it with solder. The cathodes (two) will "box" the anode, but I need to fabricate the pillars to fix the spacing plus weld the tubular lead to it (everything made of CP titanium, of course). I'll post more as I progress the job...

WSM B)

 

I didn't mention the size of the hardware or any techniques I used. I'm using 10-32 x 3/8" pan-head machine screws (Phillips) and a stainless steel alloy (304 because the hardware store doesn't have 316). I lined up everything on a hard surface and drilled into the three materials using a #21 drill with a drill stop clamped on. I drilled the HDPE bucket lid holes out with a #12 drill for clearance. I used a rotary leather punch to open the holes in the Viton Gasket. I tapped the blind holes in the PVC BCA with a bottom tap after starting the threads with a through tap. I tapped the holes without any lubricant and by hand to avoid making a mess.

 

I used twelve screws, hoping they're enough, but I can add more later if neccessary. I'm thinking about adding stainless steel or PTFE washers under the heads of the screws to preserve the HDPE lid. I also thought I might caulk the seams/mating surfaces with silicone bathroom caulk if getting a good seal proves difficult. We'll see about that...

 

I'm still debating whether to use the IV drip system for pH control, as Swede describes, or use a PTFE 12Vdc valve with a needle valve and an accurate timer like Swede describes in his blogs. I may have to ask my friend how deep he wants to wade into this pond?!! ;)

 

WSM B)

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Lucky fellow ;) :P

 

Hey sounds like he's ready for more than a pond. Maybe a lake...... :P

NIce pic's!!! Looks very promising !!!! Im sure every 2" should be enough. Washers are not a bad idea either. Acid delivery is a very nice addition to a cell. Nothing worst than missing a addition and or being out of town (using the hand delivery method).

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Great work so far Swede, looking forward to some updates.
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I didn't mention the size of the hardware or any techniques I used. I'm using 10-32 x 3/8" pan-head machine screws (Phillips) and a stainless steel alloy (304 because the hardware store doesn't have 316). I lined up everything on a hard surface and drilled into the three materials using a #21 drill with a drill stop clamped on. I drilled the HDPE bucket lid holes out with a #12 drill for clearance. I used a rotary leather punch to open the holes in the Viton Gasket. I tapped the blind holes in the PVC BCA with a bottom tap after starting the threads with a through tap. I tapped the holes without any lubricant and by hand to avoid making a mess.

I used twelve screws, hoping they're enough, but I can add more later if neccessary. I'm thinking about adding stainless steel or PTFE washers under the heads of the screws to preserve the HDPE lid. I also thought I might caulk the seams/mating surfaces with silicone bathroom caulk if getting a good seal proves difficult. We'll see about that...

I'm still debating whether to use the IV drip system for pH control, as Swede describes, or use a PTFE 12Vdc valve with a needle valve and an accurate timer like Swede describes in his blogs. I may have to ask my friend how deep he wants to wade into this pond?!! ;)

WSM B)

 

I suppose we'll go for the gusto and use the type of setup Swede uses;

 

an acid reservoir plus

an accurate digital timer and

a 12Vdc Teflon valve and

a Kynar needle valve to feed acid into

an acid dispersal tube in the bucket

(Wow, what a mouthful!).

 

It should make an excellent pH control system.

 

WSM B)

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The timer works... That Auber Instruments timer was a great find, and not too expensive. I initially thought I'd be able to use a cheap household lamp timer, but the precision is non-existent. The Auber timer allows sequential events down to the second, and having it open a PTFE or Kynar solenoid valve would make dosing easy. But the spirit of this attempt, at least, is no electricity beyond the electrodes.

 

I've fallen behind a bit in this - I'll try to get it going soon. The drip concept may have a fatal flaw... if a cell has gobs of current, it is also going to have a significant loss in electrolyte level, easily made up with a moderate drip. For a light or small system, like 10 amps on a benchtop 4 liter cell, the acid drop rate is going to be too slow, I'm thinking, like 1 drop every 20 seconds. Even a high quality chemical needle valve simply can't do this.

 

I'll do the math and figure it out one way or another.

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