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Rosco Bodine
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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?
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I think what tentacles is getting at is supposing the lithium perchlorate forms more easily , but is more soluble than potassium perchlorate , so it
would double decompose as fast as it forms and have a catalytic effect ,
regenerating the lithium chlorate as the process proceeds .
It is a reasonable idea and could be a good one if the solubilities favor the reaction .
[Edited on 18-11-2007 by Rosco Bodine]
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MadHatter
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Suggestion
I'm sure he meant double "displace". Tentacles, your idea about using a copper cathode
is interesting. As for LiClO4, the CRC, 85th edition, lists 58.7 gr/100 ml solubility at 25 C.
I'm more curious about 0 C, but I won't be able to check my older CRCs until I get home
tonight. If LiClO4 is easier to produce and the solubility is higher than KClO4, this may
be worth investigating. Again, I won't have the complete data until I get home.
Good potential suggestions in both cases however.
[Edited on 2007/11/18 by MadHatter]
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Rosco Bodine
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I rarely met a thesis I didn't like 
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hashashan
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how does KClO4 got here?
you wont get any KClO4 at all because of the low solubility of KClO3.
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dann2
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Hello,
The Li may allow you to make Perchlorate using Graphite without too much erosion as Li Perchlorate 'forms easily and in great abundance'.
Dann2
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12AX7
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Uh, yeah- hence the metathesis.
Copper must be in solution so lead goes to the anode and copper to the cathode. Copper metal on the cathode is completely out of the reaction and
does nothing further.
Why copper metal at the cathode is preferred to just losing more lead from solution, I haven't a clue. It's just what people have been doing.
Incidentially, does anyone know of a leveller for plating lead? Thiourea does nothing.
Tim
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Rosco Bodine
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The solubilities are wrong for the sodium compounds so it wouldn't work that way . Lithium perchlorate will form from sodium perchlorate plus lithium
chloride .
The potassium compounds are possibly a different matter.
Maybe hexamine or possibly betaine could help with the lead plating . I vaguely remember something to that effect ....but I'm not sure where I saw it
or even if that's right .
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MadHatter
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LiClO4
CRC, 62nd edition, gives a range of solubility(grams per 100 ml water) for LiClO4 as:
60.0 grams @ 25 C to 150 grams at 89 C.
So the metathesis with KCl should precipitate out the KClO4 very quickly as long as
a good amount of LiClO4 is in solution.
The starting materials(Li2CO3, HCl, KCl) are readily available in my locale.
As for using a copper cathode during the PbO2 plating process, I can see it won't make
a difference. Not a big deal. Copper nitrate, is easily made from calcium nitrate and
copper sulphate. Lead nitrate is only one more step. Again, the starting materials are
readily available.
[Edited on 2007/11/20 by MadHatter]
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Rosco Bodine
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Lithium Perhlorate Related Processes
Here is one patent that provides some further information .
US3020124 (attached )
Evidently lithium perchlorate is indeed useful as an intermediate in commercial production of other perchlorates via metathesis , using the carbonates
of the desired perchlorate , and recovering the Lithium Carbonate byproduct. This is recycled in the process by chlorinating to the hypochlorite and
electrolysing back to the perchlorate for subsequent batch metathesis reactions .
It still seems possible that the lithium perchlorate may act as a continuously regenerable catalyst in a potassium perchlorate cell . And if not ,
then the batch process as described in the patent could be used .
Attachment: US3020124 Lithium Perchlorate Processes.pdf (314kB)
This file has been downloaded 803 times
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dann2
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Doped Tin Oxide on Ti
Hello,
Got back to doing some 'DTO ing'.
This time I have SnCl4:5H2O (reagent), not using SnCl2 + H202 for to get SnCl4 in solution.
Not having much luck. Most of attempts I have made have resulted in a coat that is not black at all.
The colour ranges from brownish, whitish, yellowish. It appears powdery. I did not bother to try the
coating in a Chlorate cell as I reckoned it would be a waste of time.
The closest I got to a black coating is shown below.
http://i168.photobucket.com/albums/u200/anodes_2007/sncl4.jp...
Parts of the Ti are black and some parts are not.
I don't know why. It was all subjected to the same treatment.
I am using old (coated before) Ti. Perhaps I should strart with new.
Ti is eteched in hot HCl and scrubbed clean with a tooth bruch and washed in Isopropyl alcohol (surgical spirit)
then coated immediatly. Oven is at 440C.
Will try a mixture of Sn(I) and Sn(II) next.
Also tried SnCl4:5H20 in IsoP alcohol, no dopant, no HCl,..............no good.
Diluion rate does not seem to matter either.
Looking back on my notes (bearly decipherable scribbles) I noticed that the only coating that
were black in my previous attempts were made using SnCl2:2H2O (+ dopant & HCl & solvent).
Dann2
running out of excuses
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Eclectic
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Try going straight from etch to a dip coating.
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Rosco Bodine
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maybe etch Ti with oxalic acid instead of HCl
In this thread earlier I mentioned a patent that was posted over in the Hanovia bright platinum thread where on
8-9-2007 I wrote:
| Quote: |
@dann2
Oxalic acid is reportedly good for etching the titanium according to US3650861 , in preparation for a platinum plating applied by baking or
electroplating .
The DTO coatings on titanium should and would very likely go better if you tried some of the alternatives which were suggested . The volatility and
corrosiveness of your mixed chlorides is simply incompatable with what you are trying to do . The patents you were following simply did not tell the
whole story in any one example as a verbatim "how to" , and almost certainly left out details which were
"mission critical" in the abbreviated descriptions which were given .
Attachment: US3650861 Etching_TITANIUM_by_Oxalic_Acid.pdf (134.39 KiB)
attachment link:
http://www.sciencemadness.org/talk/viewthread.php?action=att... |
How come you are still trying to work with the chlorides with the identified problems intact and unaddressed by any of the possible workarounds which
have been suggested , instead of trying the searched for and reported possible solutions ?
The physical chemistry and problems involved with the straight chlorides is not going to change in three months or three thousand years . How come
you haven't tried the "oxychlorides" mixed valency polymer , or the ammonium stannate , or the cold soak first deposition layer as a prebake , when
these are more promising ideas ?
BTW , has anybody heard from jpsmith123 on the electrodeposited cobalt suboxide over titanium substrate
experiment which he last reported was about to commence ?
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chloric1
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| Quote: | Originally posted by Rosco Bodine
Here is one patent that provides some further information .
US3020124 (attached )
Evidently lithium perchlorate is indeed useful as an intermediate in commercial production of other perchlorates via metathesis , using the carbonates
of the desired perchlorate , and recovering the Lithium Carbonate byproduct. This is recycled in the process by chlorinating to the hypochlorite and
electrolysing back to the perchlorate for subsequent batch metathesis reactions .
It still seems possible that the lithium perchlorate may act as a continuously regenerable catalyst in a potassium perchlorate cell . And if not ,
then the batch process as described in the patent could be used . |
Keep in mind that when you perform this electrolysis and do the metasynthesis that the lithium carbonate is actually less soluble in hot than cold
water! Use a heated funnel and filter HOT!
Fellow molecular manipulator
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dann2
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Hello,
@Rosco
I am using chemicals that I have/can get. Don't have any Oxychlorides, etc. at this moment in time. Purchasing is not a simply matter either. Could
try etching with Oxalic as I can get Oxalic but I have a feeling that it is not an etching problem. The part of the Ti that I filed did not coat well.
It was surly 'etched' clean.
The problem with dipped coatings is that a large amount of solution comes out on the Ti strip. When you start to dry this it forms puddles where large
amounts of salts gather and are present in amounts (especially at edges of evaporating puddles) which are too large for to form a coating.
Coated some more Ti strips with various Sn concocksions. I have not had time to test them in a cell
to see how they would stant up. Most of them don't look too good.
I took a piece of glass (microscope slide) and coated with a solution of Sn(II) and Sn(IV) and baked.
The coating was black except one area which was translucant and it was also conductive.
I think I will concentrate on Glass for a while to see how I get on.
Most of the patent (relating to glass) use borosilicate glass. I have no small flat pieces of Borosilicate.
Would ordinary Soda glass do instead so long as it does not crack in the oven?
I would be inclined to presume that the glass takes no part in the actual formating of SnO2 what so ever but
the thermal expansion may have consequences, not least breaking in the oven.
I could always break a test tube and use that.... Or my 3 liter round bottom flask if all my pills run out .
Regarding colour of SnO2 films, I took this from US 0025647 Columb 7 line 10: (conductive films on glass patent)
_____________________________________________________________________
With low Sb content, 1% Sb2O3 or less. such films are substantially transparant and are practically colorless
by transmitted light. However, as the Sb content is increased, the film acquires a blue colour which becomes
darker with increasing Sb content and with about 15% Sb2O3 the film transmits a deep midnight blue color and
has generally low visible transmission.
______________________________________________________________________
My Sb content is up at the (approx.) 18% mark.
Would it be possible that Iso Proply alcohol is not compatible with my Sn compounds? Perhpas I should distill it. I am using surgical spirit which I
am presuming is pure IPA.
Later,
Dann2
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Rosco Bodine
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The things suggested are only different ways of using the materials you already have .
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jpsmith123
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My Cobalt Oxide Anode Experiments
As I'm typing this I'm attempting to coat a piece of 0.090" diameter wire with Cobalt Oxide by way of electrolysis of CoSO4 solution.
I was delayed doing this by several months because I moved into a rented house with big plans (it had a great spot for a lab) but I had to move out
shortly after moving in, because the place had water problems I didn't know about, and the landlord didn't want to fix it.
Then I moved into another, temporary place, where I couldn't do much of anything, and finally into yet another place, where I can now at least do some
small scale things, although doing anything here is a PITA.
Also, until literally just a few days ago, I had a really lousy DSL connection that was down more than up...that problem is now finally fixed.
Anyway, rather than try to coat some plates, I opted to try some short lengths of stiff CP Ti wire, first, as it would be more manageable (and it
would make more sense to do small scale until the process is proven out).
To prepare the wire, I first sanded it with 220 and then 400 grit SiC paper, then I washed it in a detergent solution and rinsed it with distilled
H2O.
Then, I anodized it for 15 minutes in 10% oxalic acid solution, to create a semiconducting barrier layer of TiO2 (with good electronic but poor ionic
conduction), which will hopefully protect the substrate, and, being an oxide, provide a good surface for the Cobalt Oxide to bond to.
The electrolysis is running at a low current density (as per the patent), and I'll probably let it run all night.
I'll report back on what it looks like tomorrow.
Update: The electrolysis seems to be going ok so far. The current is slowly decreasing, and a black cobalt oxide layer is building up on the wire.
I don't know if building up a controlled-thickness semiconducting layer of TiO2 unter the cobalt oxide was the right thing to do or not, so I will
also coat another piece of Ti wire subject to the same treatment except for the anodization in oxalic acid.
[Edited on by jpsmith123]
[Edited on by jpsmith123]
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Eclectic
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When you dip coat, keep the Ti in a vertical orientation until it drains and drys, or just SHAKE it dry.
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dann2
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Hello,
Will try the dipp, shake (or drain) and bake!
As I said in the last post I would try to get a conductive coat on a test tube just to see how easy it was for me to do.
Not very easy. I used a water + HCl +Sn(IV) + Sb paint as per a conductive coating on glass pat.
I painted the tube and dried with heat gun. The 'paint' wetted the glass surprisingly well. I would have thought
it would not. Got a good even coat of Salts when water
evaporated.
The tube when put into oven did not form a conductive coat.
I tried heating tube with heat gun (at 600C setting) and dabbing on the 'paint' using fiber glass brush. The paint would instantly dry. I was hopeing
that the tube would be at 500C somewhat like the patent....no conductive coat formed.
I resorted to using a small Propant torch and the fiber glass dabbing.
I managet to create a small area of blue, irredencent SnO2 coat over where the edge of the flame was playing on the tube. It is quite conductive. 30
ohms when probes are about 4 mm apart. Cannot get a picture as I have a sh1t camera.
The coating on the latest Ti pieces looked better today than yesterday. The coating always seem to do this, don't know if it an ageing process or my
imagination (or the pills and whiskey). One of the strips lasted about half an hour in a NaCl solution. Perhaps the coatings I am getting are good
enough to go ahead with and use as an interface between LD and Ti.
Perhaps I need a convectiong oven?
Or if I dribbled some O2 in would that help. An oxidizing atm. is needed but I was inclined to think that an unsealed oven was OK.
Dann2
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Rosco Bodine
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Forget the HCl after you have your soluble chlorides it isn't required and actually gets in the way .
Part of the advantage of that mixed valency polymer composition which I posted the patent for a few pages back , was that it wets anything with an
adherent film that sticks and leaves a persistent residue which won't wash off .....even on teflon , and that is the effect achieved even before baking . Baking simply hardens
and sets the polymer further and then converts it to a
vitreous conductive coating . But because the film forms in the cold , it blankets the substrate from oxidation during the first heating cycle , as
it transitions from the polymer coating to the vitreous coating . That keeps the titanium oxide interface layer thin and conductive .
You mentioned using test tubes as test substrates and that's fine just leave 'em whole and torch the outside
like you are doing . And don't think that an opaque black coating is what you want ...it isn't . What you should see is an irridescent bluish or
purplish but transparent coating , something like the reflective optical coatings they put on some sunglasses . You probably know that now from what
your ohm meter told you .
I'm still betting that cold coating a solid Ti rod , and chucking it in a rotisserie over a rectangular form burner and spray coating it hot , making
several passes , could end up being the best method . The only concern I have here is that on cooling , contraction fractures might appear in the
coating on a larger diameter rod , but something like 3/4" diameter or 5/8" diameter would probably be okay . Some of the Ti alloys have 2% Sn
in the alloy and this would probably improve results ,
and some have Zr as well as Sn and these alloys are probably good too . These indigenous metals would tend to contribute to the doping of the Ti
oxide interface layer
as it is forming , that contribution to the doping arising from the substrate itself .
[Edited on 25-11-2007 by Rosco Bodine]
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jpsmith123
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Well it's coated...
The wire now has a fairly nice looking, i.e., uniformly dark, adherent, cobalt oxide coating; i.e., I cannot just wipe it off, even when exerting
significant force, using a rag. Attached is a picture.
Tomorrow I'll test it in brine electrolysis and see what happens.
I also tried to coat a piece of Ti wire without the oxalic acid anodize pretreatment, and it didn't work at all. It immediately passivated in the
CoSO4 solution.
For the sake of comparison, tomorrow I will also try to apply a coating to a piece of platinum wire, and also to a graphite rod. I may also try to put
a cobalt oxide overcoat onto a pool chlorinator MMO anode.
[Edited on by jpsmith123]
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Xenoid
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@ jpsmith - Good to see you back!
That coating looks really good, I will be very interested in seeing how it performs!
BTW how did you get on with your MMO pool chlorinator anode, I'm looking to get some "used" ones over the next few months.
Regards, Xenoid
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jpsmith123
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Hello Xenoid,
I made a little KClO3 with one chlorinator cell (the sal-chlor). I also have another, heavy duty (25 amp) autochlor cell that I haven't done anything
with yet. (The completed assembly looks too good to do anything with  ...with a 4L
PET bottle, titanium hardware throughout, & viton o-rings, I can't bring myself to use it...
Actually I'm waiting to see what happens with these cobalt oxide coatings. My gut feeling is that they'll work nicely over Pt, Pt-on-Ti or MMO-on-Ti,
and perhaps over graphite as well.
Who knows, the most practical solution to the perchlorate problem may be to buy a relatively inexpensive sal-chlor cell, take it out of the box, rinse
it off, dip it into a CoSO4 solution, electrolyze for a few hours, and thereby end up with a rugged perchlorate maker.
Anyway, right now as I'm typing this, I'm coating a piece of Pt wire. Unlike the Ti wire I just coated, the current is constant in this case, and the
voltage is much lower...which makes me think the coated Ti wire has problems. Perhaps I anodized it at the wrong voltage or for too long or
something...I'll see tomorrow what happens.
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Rosco Bodine
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That "blued" band of color above the darker heavier oxide is a good sign 
As an alternative to anodization in the oxalic acid , something you might try is a mild cathodization in the hot oxalic acid solution , which should
increase the etch rate and bare the Ti even more rapidly .
After awhile at the low etching potential , increasing the negative potential will actually convert the bare Ti to an active hydride , as Ti has an
enormous adsorption appetite and capacity for hydrogen .
Whatever you apply next if you act quickly is going to have a virtually bare Ti metal interface to whatever layer is applied next . It would probably
deposit a silver metal mirror as a flash coating , if for example you dipped the hydrided Ti into silver nitrate solution . Dittos for the cobalt or
mixed tin and antimony compounds , the metals
would probably flash plate electroless and instantly onto the bared Ti .
Another possibility if you are finding a semiconductive
anodization is giving good results , is the "blue titania suboxide" produced by anodization in 50% KOH , which was described in a rectifier patent .
That particular inventor had tried many different mixtures and conditions for producing a conductive suboxide under electrolytic , non-pyrolytic
conditions , and reported that the 50% KOH
was the only one found to produce a stable conductive Ti suboxide at ordinary temperatures .
Another thing you might test is the "per-cobaltous acid"
as a chemical anodization "first strike" on the hydrided
or freshly etched titanium . This might possibly produce a cobalt doped titanium suboxide interface layer by chemical
action alone . This is pure experimental , as there is nothing in the literature concerning this , simply a curiosity
of my own that arose after reading some of the other experiments that have been described .
Also , the cold soak deposition method is applicable to the cobalt oxides .
Anyway, keep us posted on whatever results you get .
[Edited on 26-11-2007 by Rosco Bodine]
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jpsmith123
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Rosco do you happen to know the number of the rectifier patent you mentioned?
BTW I'm attaching Beer's TiO2 patent.
Attachment: 3234110.pdf (529kB)
This file has been downloaded 722 times
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Rosco Bodine
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| Quote: | Originally posted by jpsmith123
Rosco do you happen to know the number of the rectifier patent you mentioned?
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Yeah , that's the Ruben patent for an early Shottky Diode ,
US2711496
Here's the attachment link from page 15 where it was first posted
http://www.sciencemadness.org/talk/viewthread.php?action=att...
I'm still looking for the other reference on the "cobaltous peracid" I mentioned . IIRC it was simple to make using H2O2 added to cobaltous
hydroxide . I was thinking that perhaps this might have an effect similar to chromating ,
which can produce a semiconductive and corrosion resistant
very adherent interface , thinking it just might result in a
Titanium Cobaltate "bluing" effect , which would also likely have good adhesion for the cobaltous suboxide applied by electrolysis as the next step .
dann2 is betting on the black stuff being the conductive interface , but I am still putting my money on the blue
Basically this whole semiconductive boundary layer scheme
is indeed the construction of a planar Schottky Diode which
will be operated reverse biased as a Zener , the goal being
the minimization of the reverse breakdown voltage . So
the boundary layer is being doped to optimize its conductivity
in order to minimize the natural rectifying tendency which is exactly opposite the direction of current flow when the cell
is making perchlorate . In this scheme the alloy of titanium
chosen for the substrate definitely will have bearing on the conductivity of the "sandwich" of layers , and so will the additives in the PbO2 or other
layers , everything involved
has its own contribution in doping the junctions in the diode structure .
One other possibility I have wondered about is bismuth compounds with cobalt ,
such as bismuth cobaltate , or
cobalt bismuthate ...are these possible and what usefulness
might they have in regards to perchlorate anodes ?
[Edited on 26-11-2007 by Rosco Bodine]
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