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The Bucket Cell - Start to Finish


Swede

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i am not sure what the problem was. i cut the mmo with a disk grinder. or the ti tube I used was not as pure as I thought

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i think i figured out my black water problem. I got rid of the titanium tube I used to mount the mmo and I used the second half and gave it a try. also used the uncut end of the mmo in solution. I have 12 hours run time, no black water. hope I have it figured out.

memo

 

Hi Memo,

 

I'm wondering, what grade of titanium is the tubing you used? I ask because alloyed titanium can have metals included which are incompatible with the environment of the cell.

 

Also, what material is the cell container constructed from? One of my first experiments (over ten years ago) used an HDPE container for a cell which started to deteriorate and leave black flakes floating in the cell, as the chlorination progressed.

 

The more details you can share, the more likely we can discover what caused the issue...

 

WSM B)

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i am not sure what the problem was. i cut the mmo with a disk grinder. or the ti tube I used was not as pure as I thought

I usually cut my MMO mesh with a hacksaw or some other thin blade metal cutting device. The bare titanium edges don't cause any problems in the running cell because of the nature of CP titanium.

 

I search carefully for CP grade titanium tubing for use as leads for my electrodes. The thicker walled tubing seems to form very well when heated repeatedly while forging.

 

WSM B)

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I have a 93 hours on this run, I tested it with some methaline blue and I did get a violet color. going to run for a couple of more days. first time to get a positive test for perchorate

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  • 2 weeks later...

I have a 93 hours on this run, I tested it with some methaline blue and I did get a violet color. going to run for a couple of more days. first time to get a positive test for perchorate

 

That's interesting.

 

Is this is a sodium chlorate cell, running with MMO and titanium electrodes? I thought perchlorate production wouldn't happen with MMO due to its lower oxygen potential (as opposed to platinum or lead dioxide).

 

Please tell us more details when you can. Thanks.

 

WSM B)

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  • 3 months later...

I noticed laserred is selling MMO mesh anode material on eBay; 3" x 10" (~75mm x ~250mm) for 20 USD. The price is reasonable considering what other sellers are charging (check the listings on ebay).

 

It could be used whole for a large (high current demand) cell or cut into smaller pieces for smaller cells. Paired with CP titanium sheets for cathodes, these anodes can produce huge amounts of chlorate over their lifetime, if proper care is taken to provide optimal conditions for its survival.

 

WSM B)

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(1) Well, my workshop/man cave is coming together nicely. I've got a friend who's a contractor that offered to hook me up with solar panels and equipment at cost. I plan to use battery backup with a controller and inverter as well. I'm seriously considering it to use as supplemental power for my projects.

 

(2) My current plans are to run a 240 Vac line from the house to a subpanel I mounted inside, which will feed 120 Vac power to the lights and power outlets plus a 240 V outlet for higher power equipment.

 

(3) If I do the solar option, it'll be a separate wiring setup, with an option to feed extension cords to the house for temporary emergency power for the refrigerator and some lights. We don't loose power often, but it's nice to be prepared if it does happen.

 

(4) I'm also considering adding a heat pump to the workshop, for heating/cooling and year round comfort when I'm working out there. It's good to learn that there are affordable options in this venture. It's especially nice to have a separate structure to house my projects,

 

(5) and my Wife is happy to see the back yard get decluttered of all my experimental bits and pieces.

 

(6) I'm planning to move my covered workbench to just outside the workshop and have a covered outlet already in place. I may build an enclosure for the electrochemical experiments as sort of a lean-to on the workshop, with proper venting, lights and accessories in place. We'll see how this develops...

WSM B)

 

UPDATE: It's been almost a year since the quoted post, so let me bring everyone up to date.

 

(1) I've finally committed to going ahead with the solar project, scheduled for after next weekend. My contractor friend is arranging for all the pieces and I'll send funds to cover the expenses when we get a hard quote. The expectation is that it'll provide enough power to be the main electrical source, plus have surplus power to feed back to the house in case of a power outage, using extension cords (not a fixed, permanent setup).

 

(2) My plans to run a line from the house are on hold. I originally planned to trench between the house and the workshop and run underground power between outdoor rated boxes mounted to each structure.

 

I'm currently feeding power to the workshop through an extension cord and back feeding an exterior outlet to an interior mounted sub panel for lights and outlets. The sub panel has 6 positions, two 15 Amp circuits for lights (all of which are LEDs to conserve power), two 20 Amp circuits for power outlets set up for running tools and other equipment, and one 240 Volt AC breaker for higher power-demand tools.

 

(3) I've decided to do solar as the primary source of power for the workshop, rather than as a supplemental source, keeping it off-grid. I'll use the existing wiring and only have to rearrange the feed to the sub panel when the solar system and its components are installed. The solar system (including battery backup) is designed to provide all the power needed and duration for all my planned operations (and more) plus have surplus electricity to support essential services for the house, in case of a power outage.

 

(4) The heat pump (air conditioner plus area heater) is still in the future, but it'll become essential if the weather gets more extreme as it appears to be trending. The heat pump is a two part system with a small output vent plus controls indoors, and the bulk of the equipment outdoors. They're getting to be highly efficient and using less power than older units required.

 

It's very nice to have a separate structure to house my projects. A problem is that it tends to get a bit crowded (with stuff) and I need to rearrange things from time to time, to keep it workable and not just a storage space :(!

 

(5) To be honest, she's not as happy as I had hoped because ALL my bits and pieces don't fit in there and still afford room to work :huh:. She doesn't mind me HAVING stuff; she just doesn't want to SEE it :o!!! A clear yard with grass and flowers (and not any visible junk) are more to her liking. I can't say I blame her (I often wish I lived where we had more space, rather than in the suburbs of a large city)!

 

(6) This hasn't happened yet. One thing at a time. Getting that set up is a priority, but after more critical parts are completed. When it's moved and set up, I plan to get back to my research in earnest (Yay! :D).

 

WSM B)

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A Water System!

 

Along with other projects, I've decided to build a water storage system for emergency preparedness. I live in "earthquake country", and storing emergency supplies and equipment is recommended and prudent in my area.

 

Since the quality of our tap water is wretched, we use an RO purifier for any water we drink or cook with (and the ice maker in the fridge, too). I thought storing tap water wouldn't be as practical as making and storing purified water. To that end I've collected several components for making and storing purified water in some large water storage barrels, for emergency use.

 

My thoughts are that it's better to store water that's ready to use instead of something that needs work before it can be consumed. Using a separate RO system with hefty prefilters is what I planned for, with a catch barrel for the purification system runoff, to be used for watering the garden and yard (rather than let it drain to the sewer and waste it).

 

For safety and quality, the system will be housed in a shed for the purpose, which will afford protection from the elements.

 

With a stored water system in place, it seems a simple matter to add a supplementary system to make and store either distilled water and/or deionized water to use for the electrochemical cells or batteries (which are also electrochemical cells, of course) and any other purpose such water is used for.

 

These ideas have developed in the course of my research into electrochemistry as well as emergency preparedness, which has been part of my thoughts for a MUCH longer time.

 

WSM B)

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A few years ago I came across a great find at a yard sale my neighbor was having. I found and bought (for a pittance), a small kitchen counter, water distillation apparatus. This device is enclosed in a stainless steel housing and appeared to be missing a few parts. The space it takes is roughly one cubic foot.

 

With a little work I managed to clean it up and set it up for a trial run. It has a mechanical timer and limited capacity, but when I ran it using some water from my kitchen RO system (~5-50 ppm of dissolved solids, as opposed to ~300-500 ppm tap water), the water dispensed from the device was reading zero ppm dissolved solids!

 

The distiller isn't super efficient, running off an electric heating coil, but when I calculated the actual cost of operation including my electricity rates, I can make distilled water for half of what buying it from the grocery store would cost, and even less if I set it up and run it on my soon-to-be-installed off-grid solar power system.

 

I have the distiller stored on a shelf at the moment, but when I get going on my electrochemical research in earnest, it may play a part in keeping me well stocked with lower cost distilled water.

 

WSM B)

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  • 3 weeks later...

building a new cell my old one was a gallon the new onw is 2 1/2 gallon. what is the biggest cathode and anode can run. mmo and titainium and using a computer power supply at 5 v

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Probably depends more on your ability to make an interleaved electrode assembly and have it fit into the cell easily.

 

What current rating is your PSU 5v rail? Aim for 90% of that rating. Maybe use a length of iron (gas) welding wire as a current limiting resistor, or a big array of ceramic or alloy body resistors. At 5v I'd expect to need some current limit I've seen 4.2V at 10A Most of the voltage raise needed is to overcome the resistance of the entire circuit, nuts, bolts, washers, good copper wire.

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  • 3 weeks later...

Probably depends more on your ability to make an interleaved electrode assembly and have it fit into the cell easily.

What current rating is your PSU 5v rail? Aim for 90% of that rating. Maybe use a length of iron (gas) welding wire as a current limiting resistor, or a big array of ceramic or alloy body resistors. At 5v I'd expect to need some current limit I've seen 4.2V at 10A Most of the voltage raise needed is to overcome the resistance of the entire circuit, nuts, bolts, washers, good copper wire.

 

Current electrical best practices call for running loads at 80% of a supply's capacity (Amperage, not Voltage). This is conservative and probably based on the inrush current of motor loads, and other such demands, but it pays to not overload your supply (plus leave room for unexpected "surprises").

 

Sorry, I do electrical work for a living, and electrical theory is behind a lot of my thinking.

 

WSM B)

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building a new cell my old one was a gallon the new onw is 2 1/2 gallon. what is the biggest cathode and anode can run. mmo and titainium and using a computer power supply at 5 v

 

The size (area in cm2) of your electrodes has more to do with the current (Amperage) you can supply, while not exceeding 0.3 A per cm2 of surface area (less is okay, more is ill advised).

 

The Voltage is "electrical pressure", and the Amperage represents the "volume of electrons" flowing. You only need enough Voltage to drive the reaction. Amperage (current) demand is based on the "real estate" (or area) of your anode with matched cathode(s).

 

The answer is based on the average current output of your power supply, then sizing the electrodes to demand about 80% of that amount, to keep things running without overheating the power supply unit (PSU).

 

WSM B)

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  • 5 months later...

The longer I think about Swede's description of a bucket cell, the more practical it appears to be.

 

To be honest, my first (failed) attempt at a chlorate cell was set up in a 5 gallon HDPE bucket with a lid. I tried to use a graphite anode with a stainless steel mesh cathode. What a mess!

 

Needless to say, I've moved on and achieved considerable success since then.

 

Now, as for the bucket cell, I readily admit that the bucket wasn't the problem with my first attempt. Everything else was!!! Swede's major breakthrough was using a thick PVC plate for his BCA, or bucket cell adapter.

 

I know PVC is a compatible material in the chlor-alkali cells we build, but realistically, little if any of the electrolyte ever contacts the lid of the cell, so other polymers may do an adequate job as a BCA.

 

I suggest that the best design of a chlorate cell is one where a gap of about 100mm to 150mm (4" to 6") exists above the cell liquor for ample space to allow the hydrogen bubbles to pop and reduce the tendency to promote salt creep, which causes problems for electrical connections and other incompatible materials outside the cell.

 

I'm considering whether I should try a BCA made of clear acrylic plastic of about 3/4" (~19mm) thickness?! If it works (and it just may), it would represent a great savings over thick walled PVC plate, PLUS be MUCH easier to source.

 

Any thoughts?

 

 

WSM B)

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One problem I had was that a nylon cable tie I wanted to use lasted just less than ten minutes when in electrolyte spray.

 

Polypropylene ( PP) was OK as a cell material, and available as nice size lidded jugs from Asda(Walmart) cheaply (£2 -5) intended for keeping juice in the fridge. Always used inside a safety bucket.

 

The down side of PC power supplies is that with changing mobos the need for 5v decreases and the need for 12v increases, so a big psu that would have a 25a 5v rail has evolved into a 10A 5v rail and a 12vrail at 30+ amps. China sends the world single rail PSUs and I've seen 5v 100a on ebay Once you talk of even 50a the wire you use becomes critical, fat wire of good copper works but CCA wire suddenly shows it's limitations, and most domestic 50a wire is rigid unless you pay lots for welding wire.

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Nylon is totally incompatible with the cell liquor. I'm not certain how well acrylic polymers will hold up, but since we're discussing a thick piece in the lid above the liquor, it may work out.

 

As for power supplies, I've never used a PC power supply to make oxidizers. My best power supplies have been variable, and some with CV and CC capability. I HAVE used some without the CC mode available; and the powerful, rack-mountable types seem to work well for chlorate cells, IF I tailor the electrode size to the output of the power supply.

 

I moved up to using welding cable years ago, for leads on my higher powered supplies. I prefer them for hooking power to my electrodes which are mounted through the lid of the cell, using PVDF compression fittings (as described in Swede's blogs).

 

WSM B)

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I found a 60a 5v psu as a Chinese internal fitting unit with lots of vents in the case and a little adjustment. It works fine, the leads are fat speaker wire.

 

Initially the leads were quite long and they were cut down to increase the current! I can now set the current about 25a with ease and it stays cool over a week of operation.

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I found a 60a 5v psu as a Chinese internal fitting unit with lots of vents in the case and a little adjustment. It works fine, the leads are fat speaker wire.

Initially the leads were quite long and they were cut down to increase the current! I can now set the current about 25a with ease and it stays cool over a week of operation.

Very nice. It sounds like a workable option for a decent sized chlorate cell.

 

WSM B)

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  • 4 months later...

My work on making pure oxidizers has just taken a big step forward. I just ordered a DI filter which, when added to an RO system will make deionized water.

 

With pure water and purified starting chemicals, my products should be equal to (or better than) commercial oxidizers.

 

WSM B)

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  • 2 weeks later...
Wow topics getting juicy. Can't wait till my work slows down. I wan to jump in on the band wagon and get my system dialed in to contribute to the thread. Sucks being your own boss. Hard hours and a a- hole of a boss to contind with😋.
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Wow topics getting juicy. Can't wait till my work slows down. I wan to jump in on the band wagon and get my system dialed in to contribute to the thread. Sucks being your own boss. Hard hours and a a- hole of a boss to contind with😋.

 

Yeah, I want to get going on my system, too!

 

Years ago I was self employed, also. The worst part was, I had a jerk for a boss!!! );

 

WSM B)

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  • 1 month later...

I just got a new computer (reasonably powerful with loads of memory). It's astounding how handicapped I've been without one for over half a year now. Tapping on a keyboard is so preferable to poking at my cellphone.

 

Part of the reason my research on homegrown oxidizers has stalled is due to the lack of proper tools (that, and making the time to continue my research), and this new computer is liberating. Now if i can recover the data stored in the old one, I'm off and running :D!

 

WSM B)

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  • 2 weeks later...

In my high temperature sodium chlorate cell experiment, I bought a piece of 3/4" (~19 mm) grey PVC plate to use for a cell lid. Since I've subsequently acquired some PVDF plate to use instead, I plan to use some of the thick PVC plate to make a prototype BCA (bucket cell adapter; see Swede's Blog and the first few posts to this thread).

 

If the BCA were made by carefully machining it for uniformity, this would potentially be a great model for a commercially available product. Imagine if a router guide were included with it for ease in fabricating a matching hole in the bucket lid?!! How many more amateur electrochemists would make bucket cells their norm if such an item could be purchased online?

 

What do you think?

 

(Heck, I'd buy a couple, if the price were right!)

 

We'll see what the future holds.

 

WSM B)

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