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dann2
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Hello,
From one of the patents:
________________________________________
Ceramic particles are preferably incorporated in the electrolyte solution because these particles, when suspended in the electrolyte as by constant
agitation, prevent oxygen bubbles from clinging to the substrate anode during the electrolysis and consequently eliminate the formation of holes in
the lead dioxide deposit. Typical ceramic particles are minus 325 mesh ceramic beads and, when employed, are used in a typical concentration range of
1 to 10 grams per liter.
______________________________________________
It is a while since I read the patents.
Ceramic particles it says. Glass beads I thought it said.
Minus 325 mesh. 325 mesh corrosponds to particles about 44 micro meter in diameter. (I don't know what the minus means, 44 micron and smaller??)
Since the Lead Nitrate solution is dense the beads/particles will stirr up and stay suspended with stirring.
I wonder would course sand do instead. You would need to heat the sand to a high temperature to get rid of all organic's (if they where there to start
with).
Never used ceramic particles myself.
I presume the action of the particles is harse enough to remove bubbles (easy to do) and gentle enough not to damage deposited LD.
Dann2
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dann2
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Stannic Chloride (Hens teeth)
Hello,
A bit off topic but.....
Some Stannic Chloride on ebay.
USA sales only, will not post to Europe.
Is there any good soul (in the USA) willing to purchase and post to Europe.
TIA.
Not much time left.
Forgot url.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&...
Dann2
[Edited on 20-10-2007 by dann2]
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Intergalactic_Captain
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Not sure if this has been posted yet, but the attached file has a bit of info the use of tantalum as a substrate...Still a bit expensive, but no more
so than Ti/Pt. They acheived very thick (.5cm+) deposits with a high rigidity - "the wire was removed with a sharp pull from pliers." 3 baths are
discussed, one an improved Pb(NO3)2 as well as a tartrate and perchlorate bath.
The process seems simple enough, basically very long plating times at <.02A/cm2...Thick, strong deposits. What I wonder is if this might be
possible as a GSLD.
One other thing - Ti/Pt is expensive, but I've got access to Ti scrap in small amounts...Would palladium work, or would the oxide be non-conductive?
It's only about 5x cheaper than platinum on the current markets, but still over $300/oz.
Attachment: pbo2 anodes - very good.pdf (434kB) This file has been downloaded 1525 times
If you see me running, try to keep up.
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Xenoid
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Quote: | Originally posted by Intergalactic_Captain
One other thing - Ti/Pt is expensive, but........ |
Well the initial cost might be fairly expensive, but given what various people in this forum are spending on time, effort and chemicals trying to make
alternatives it's starting to look cheap!
I bought a small Ti/Pt electrode from Palloys (Australian company) the cost was about A$50 (~US$45) and post was next to nothing because it was so
thin and light!
http://www.palloys.com.au/category7_1.htm
Hey..... and it works! I've made a couple of Kgs of KClO4 so far. I'm now looking at MMO anodes for chlorate production.
Regards, Xenoid
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dann2
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Hello,
Someone spending large amounts of time and cash on chemicals and equipment.... wonder who that is ?
Moving swiftly along...........
Did you obtain any details of thickness of Pt coating on Ti?
What sort of conditions are you using it under and is your Chlorate (I am presuming you are starting with Chlorate or are you starting with Chloride
and going all the way to Perchlorate) totally free from Chloride.
Are you using an additive like Dichromate?
Of course if you get bored making all that Perchlorate you can always use it as a substrate for a ..........
Cheers,
Dann2
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dann2
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Hello,
Do you mean to use Palladium Oxide as an undercoat between the Lead Dioxide and the Ti substrate?
Palladium is not 'Noble' enough to use in a Chlorate/Perchlorate cell to the best of my knowledge. Only Pt and Iridium will do. Not too sure about
pure Iridium but it is use alloyed with Pt.
Don't know about oxides of Palladium being suitable as an undercoat between Lead Dioxide and Ti.
I am tempted to purchase the anode Xenoid has shown as a substrate for an Anode but it would be much too easy and straighforward. Why do that when
there is another more time consuming method with no guaranteed successful outcome.
There is virtue in hardship
On a more serious note if one were to purchase the Pt'ized Ti anode as a substrate it could be used again and again as the Lead Dioxide fell off. (so
long as it stayed on for a sensible time). If it turned out that you simply could not make a success of Lead Dioxide plating you would still have a
perfectly good anode to use for Perchlorate.
I have read reports of people using Platinized Ti anode in the past for (Per)Chlorate making and they complained that the anode failed. Perhaps they
were abusing it.
Dann2
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chloric1
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Quote: | Originally posted by Xenoid
Quote: | Originally posted by Intergalactic_Captain
One other thing - Ti/Pt is expensive, but........ |
Well the initial cost might be fairly expensive, but given what various people in this forum are spending on time, effort and chemicals trying to make
alternatives it's starting to look cheap!
I bought a small Ti/Pt electrode from Palloys (Australian company) the cost was about A$50 (~US$45) and post was next to nothing because it was so
thin and light!
http://www.palloys.com.au/category7_1.htm
Hey..... and it works! I've made a couple of Kgs of KClO4 so far. I'm now looking at MMO anodes for chlorate production.
Regards, Xenoid |
IMHO I was under the belief that the platinum coating was to thin and frail for perchlorate use. You made a couple kilos of Potassium perchlorate?
May I assume you started with sodium chlorate and generated the perchlorate and performed metasynthesis. Details details! PLEASE!
Fellow molecular manipulator
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Xenoid
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Quote: | Originally posted by chloric1
IMHO I was under the belief that the platinum coating was to thin and frail for perchlorate use. You made a couple kilos of Potassium perchlorate?
May I assume you started with sodium chlorate and generated the perchlorate and performed metasynthesis. Details details! PLEASE! |
Well as far as I know, platinised anodes are designed for perchlorate cells. I've just had a good look at my Palloys anode and it seems OK, perhaps a
little corrosion starting on the edges. I will be very annoyed if I can't make at least another couple of Kgs with it. If I can make 5 Kgs in total I
will be quite happy, that will work out at about $10/ Kg. Actually, I'm not sure what I'm going to do with the 2Kg I have already. I got into
(per)chlorate making because I thought I would not be able to obtain cheap KNO3 for rocketry anymore, with NZ tightening it's legislation on the sale
of "hazardous substances". So I thought I'd have a go at APC. In the meantime I've located a new source of KNO3, so now I'm not so interested in
(per)chlorates.
My perchlorate procedure was essentially as outlined on Dann2's pages. I used a 1.5 litre pickle jar and the starting solution was near saturated,
pure (twice recrystallised) sodium chlorate, the cell had about 760g NaClO3 in it. The electrode assembly is shown in the top image, I used two 9.5mm
Ti rods for the cathode. Running a perchlorate cell is a dream, clear solution, no chlorine, no smell, no corrosion, etc. I ran it for about 4-5 days
at about 15A. I can't remember the details as it was a few months back and I stupidly didn't take notes (as usual). KClO4 was precipitated with
saturated KCl solution, I just kept dribbling it in until no more precipitate formed. The description on Dann2's and Alan Yates site about it looking
like yoghurt is exactly right. I then cooled the solution and filtered it in a pressure filter. The moist KClO4 was scooped out of the pressure filter
and put in plastic containers. I did two identical runs, each produced about 1.2Kg of moist KClO4, which theoretically should be about 1Kg each of
dried material. The moist KClO4 is shown in the lower image, I still haven't got around to drying it. It's been in the fridge since I made it, it
looks like ice cream now!
I called into the local swimming pool - spa centre today, they had two used MMO chlorinator assemblies sitting on a shelf. i spoke to the assistant
(the boss never seems to be there) who said they replace quite a few over summer. They looked OK to me so I'm hoping to get several to try out in
chlorate cells. I've had enough of the filthy gouging rods. The assistant wouldn't commit on a price though!
Edit: Changed reference to yoghurt from Dann2 to Alan Yates!
http://www.vk2zay.net/article.php/79
Edit: Changed reference to yoghurt from Alan Yates to Dann2 and Alan Yates! Christ I'll get this right eventually!
http://www.geocities.com/CapeCanaveral/Campus/5361/chlorate/...
Regards, Xenoid
[Edited on 31-10-2007 by Xenoid]
[Edited on 1-11-2007 by Xenoid]
[Edited on 3-11-2007 by Xenoid]
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12AX7
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Ya know, I'm looking at platinizing Ti with a PtCl6 solution, which so far has been stupid easy getting a clean plating. Pt can handle serious
current densities, like, 300mA/cm^2 or more, which implies a sheet of titanium, about 4" (10cm) wide by 18" tall (45cm, maybe 15" (38cm) in use) could
handle 228+ amperes, fitting into my cell. That's a substantial current, especially for something as resistive as titanium! So, it occurred to me, I
wonder if they make a titanium-clad copper product? ...And it turns out they do, and not only that but they also make such a product that's platinum
plated in various micron thicknesses!
Get your hands on a chunk of that stock and you'll be sitting pretty good. I don't know how they handle the ends though. Obviously, it's not
possible to cut the active end to length, or else the copper core disappears in a few hours. It should be sealed conformally. Curiously, the stock
is listed as easily weldable, which I suppose assumes TIG at the very least, and probably an argon glove box. Maybe the copper is a good enough
heatsink not to melt or diffuse into the titanium, I don't know.
Now that I've worked you all up, I don't happen to have a source for this stuff. It's probably horribly expensive. It would be well worthwhile
though. Get ten grams of H2PtCl6, put in solution with some HCl and plate out a gram each time the current gets kinda low. The 100s-micron plated
stock could last for years, maybe even decades, producing prodigious piles of perchlorate product for the private person (ooh, a spontaneous
alliteration).
Tim
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chloric1
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@Xenoid-That is pretty nice I have a few hundred grams of sodium chlorate that
I made as you know from this past August/September. Sunday, I recystallized from distilled water and when I have time, I am going to dry and package
it. It would be prudent though for me to test for chloride and barium ions. I know there are places here in the US that sell the same anodes. I will
have a look.
Fellow molecular manipulator
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Fleaker
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I have some small titanium anodes that I can make available to you all. 12AX7 has a few of them, they're approx. 8cm by 1 cm wide by 2.2mm thick of
pure Ti. To my knowledge, they worked well for 12AX7 who plated some Pt onto it.
He and I are now collaborating on electrode design. He has a ready cell and power supply for it, I have the Pt (and shortly the larger Ti plate) for
him to use. Soon, very soon.
Neither flask nor beaker.
"Kid, you don't even know just what you don't know. "
--The Dark Lord Sauron
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12AX7
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Those small bits of Ti are almost useless -- spray and ozone and other unsavory things inevitably corrode anything you have clamped to them.
Rememer Fleaker, 4 x 18" plate...
Tim
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Eclectic
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There is some 5x12" CP grade 4 Ti plate, .060 thick, on Ebay at a reasonable price on a regular basis from this guy:
http://search.ebay.com/_W0QQsassZthe_liquid_steel
They have gone for under $10 each in the past. I'm thinking Ti tubing could be TIG welded to plate and filled with cast aluminum to bring out the
electrical connection. You could cast in or thread in a copper insert at the end. Molten aluminum should wet CP titanium. (AFAIK. You might need a
fluoride flux.)
[Edited on 11-2-2007 by Eclectic]
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Fleaker
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Quote: | Originally posted by 12AX7
Those small bits of Ti are almost useless -- spray and ozone and other unsavory things inevitably corrode anything you have clamped to them.
Rememer Fleaker, 4 x 18" plate...
Tim |
I suppose on the bigger things. For small stuff and currents like plating out gold in a little cell, I've used them and they work absolutely fine. I
actually meant that Pt plated out on them well.
Neither flask nor beaker.
"Kid, you don't even know just what you don't know. "
--The Dark Lord Sauron
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dann2
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Hello,
The Doc. attached is 'Controlled Valency Semiconductors' from
Philips Research Reports, 1950.
It was referenced in one of the patents using Doped Tin Oxide as a coat between Ti and Lead Dioxide.
Thought it might contain some useful info.,,,,, it does not IMHO.
Dann2
Attachment: val.pdf (1.6MB) This file has been downloaded 603 times
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hashashan
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Well guys I think I have an update.
Recently I was working on a massive anode.
The anode was grown from a piece of Ti through a thick (about 4mm) piece of plastic fiber cloth(aka scotchbright). The setup had controlled
temperature of 50-58(sometimes it went higher.... I wasn't around to babysit it, corrected it as soon as I could) at the begining it even had PH
controll (some PbO that I dumped inside and a magnetic stirrer) but later I ran out of PbO so added NaOH solution from time to time to keep the acid
down. Also I added some ceramic dust and shreads as dann2 wrote, It seems like it helped, almost no bubble pitting at all.
I ran about 1 amp(30-40 ma/cm) current for 3 days and today my setup caught flame, probably because of the heating system that was just a thermosensor
and a heating element in a plastic bath with water(I guess the it ran out of water and inflaminated). So I had to take the anode out, however the
anode was already nearly complete, it is about 5mm thick in the center and really overgrown on the sides(I tried to prevent it by building a hot melt
glue farame for it to grow inside but it overgrew it on the first day, so on the sides its about 1cm thick.
It peeled quite easily from the Ti strip.
The anode is big, about 3.5cm*10cm and it weighs 175gr.
Ill post some pictures today when Ill get back home from work.
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Xenoid
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Quote: | I ran it for about 4-5 days at about 15A. I can't remember the details as it was a few months back and I stupidly didn't take notes (as usual).
|
Hmmmm... No this isn't correct. I found a note I'd made on a calendar. The first run was started at 1.00pm on Sat 28th July and ended on Wed 1st Aug.
I recall going down to check the cell early in the morning and noticed much increased oxygen production from the anode, so I assumed it had finished
making perchlorate. So that's about 3 days and 20 hours. The current was noted as only 6 amps although I may have increased it to 8 amps later. This
makes more sense when you look at the run times on Dann2's pages. The 15 amps was what I was running my last chlorate cells at. When you get older
don't start relying on your memory - take copious notes!!!
Regards, Xenoid
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chloric1
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I am ony 35 and having problems with memory already. I sometimes find unlabled containers of some salt I made and I cannot remember what it is Yeh I can
test it but what a f%^%$ pain when my time to experiment is so short anyways. To add to my frustration, I am almost out of soap and it can be time
consuming to make, not to mention curing times. Heated soap is usefull immediately but dissolves immedately and is soft for a week or two. So I may
need to buy 2 weeks worth of soap Sorry about my ranting I am hungry and tired and my 2 year old wants to play.
Fellow molecular manipulator
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Xenoid
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Quote: | Originally posted by chloric1
I sometimes find unlabled containers of some salt I made and I cannot remember what it is |
Yeah! I had 4 or 5 beakers half filled with "stuff" (actually I think they were mainly KOH solutions with various contaminants) left on my bench. I
had to throw them out. All that was required was to make a quick note with marker pen on the side. I don't label because I think I'll be doing
something with it the next day, but when that drags on to days, weeks and even months there is no hope of remembering. Always make notes, no matter
how trivial it may seem!
Regards, Xenoid
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dann2
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Surfactant, ctab
Hello,
There is an artical here about the use of CTAB in plaitng baths.
Dann2
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tentacles
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I spent some time looking for Igepal CO-880 and CTAB, and I did find CTAB, it was quite expensive and from a chemical supplier that probably won't
sell to a private citizen. It was like $35/25g. Plus whatever they want to charge for shipping.
edit: changed to CO-880, rather than CO-800
[Edited on 17-11-2007 by tentacles]
regarding the ceramic particles in solution that are mentioned above as a substitute for surfactants, I wonder if diatomaceous earth would be a
suitable replacement, or if the particle size is too small? I will also get some "silica flint" (SiO2, 325 mesh) from my local ceramics shop and try
that.
Also, for future reference: if you use copper cathodes for plating PbO2, you don't need to add any copper nitrate; why plate copper onto copper and
add more HNO3 to the solution? The reason for adding Cu(NO3)2 is to plate copper onto the (non-copper) cathode preferentially to the lead ion.
[Edited on 18-11-2007 by tentacles]
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tentacles
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I didn't want to double post, but I'd like for some of the smart types here to consider this: what if you put a small amount - say 1%, of lithium
chloride in each batch of sodium chloride (or even potassium chloride) when starting a perchlorate cell? Would the lithium (which reportedly forms
perchlorate quite easily) form chlorate/perchlorate, and double decompose with the Na/K ions, or is this just a wild/crazy idea?
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hashashan
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why would it double decompose?
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Xenoid
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Quote: | Originally posted by tentacles
I didn't want to double post, but I'd like for some of the smart types here to consider this: what if you put a small amount - say 1%, of lithium
chloride in each batch of sodium chloride (or even potassium chloride) when starting a perchlorate cell? Would the lithium (which reportedly forms
perchlorate quite easily) form chlorate/perchlorate, and double decompose with the Na/K ions, or is this just a wild/crazy idea?
|
I don't entirely understand the point of this, you can run a (per)chlorate cell using just about any chloride. If you want lithium
chlorate/perchlorate start with 100% LiCl. NaCl is the usual starting material because it is cheap and readily available, and the highly soluble Na
chlorate/perchlorate can be converted (using double dissolution) to other chlorate/perchlorates at some later stage. What is the point of adding 1%
lithium chloride, it's just going to behave like a contaminant!
Regards, Xenoid
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hashashan
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Lithium chloride is converted to perchlorate easier then the sodium salt. He was saying that the 1% will form the perchlorate and immediately react
with the sodium chloride to form sodium perchlorate and lithium chloride and so on ...
I don't think that there is a reason for that
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