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Author: Subject: When Chemistry Goes Wrong
tsathoggua1
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[*] posted on 30-3-2017 at 08:39


Use of plastic keck clips during a synthesis of ICl. Even the traces making it through the vacuum grease applied round the outside of the condenser joints are pretty damn virulent, enough so that after a few hours, there are breaks right through any such clip on the side closest to the joint mating surfaces, and after a day, multiple breaks. After several days, the plastic clips were way beyond saving, having been reduced to crumbly, keck-clip shaped pieces of what used to be plastic, but now has the consistency of crumbly cheshire cheese and never mind pulling the clips off the joint, they just fell off in little pieces.

Its brutal to the dow-corning high-vac grease used as a temporary measure to reduce trace emissions still further, it turns black and plasticizes into something stiff but crumbly and brittle.

Definitely not a reagent that one would wish to breathe in. Mask filters get changed before every synthetic run, and if needs be, during the run, away from the actual process itself. About to change into a brand new set of filters even though the ones in that mask currently are not spent. Its not something that would be a good idea to rely on detecting smell, after seeing what it does to organics, and the fact it hydrolyzes rapidly on contact with water (a couple of drops from a pipette into H2O resulted in a little green puff of Cl2 and some I2 as it instantly hydrolyzed) into Cl2 and I2, I'm not risking even one whiff of the stuff.
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[*] posted on 30-3-2017 at 09:55


So I read about the reaction of Titanium metal with Hydrofluoric Acid in a book. Woelen hat demonstrated pretty well how hard it is to get Titanium into solution, especially with HCl. So I tried the same thing with 40% HF in a wax-coated test tube at cold temperatures (because you have to boil it in HCl). It immediatly reacted with the Ti wire I added and so I placed the whole thing into an old plastic container I found with a transparent lid so I could film into the tube. It turned purple then it suddenly started to turn all crazy from just a small piece of Ti fumes of HF came out the test tube rose to the lid and in seconds ate through some layers of the plastic. The video will be uploaded soon to youtube but it was really crazy. I didn't expect HF to be that corrosive. It's still just a rather weak acid similar to HCl, it eats through oxides because of an interesting mechanism which increases electron density on bridging O-Atoms but for the rest of chemistry its still a regular acid. Really weird and I was lucky (wearing 3 pairs of gloves) and behind a blast shield that the stuff reacted in the box. Still just opening the lid and walking away caused my lips, so pretty much any wet part the HF could reach to become all rough for 2 days...



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[*] posted on 30-3-2017 at 19:16


Well, considering that none of my neighbors noticed any nasty fumes last night, I guess not much chlorine was produced.

I think possibly the fumes weren't actually chlorine but were instead chlorine dioxide from dissolved carbon dioxide reacting with the calcium hypochlorite. There shouldn't have been much carbon dioxide in solution, but I can see how there might have been enough to cause noticeable quantities of irritating fumes indoors.

Oh and I did destroy a couple of plastic Keck clips with bromine fumes a while back. I have stainless ones now, but I use them infrequently.

[Edited on 31-3-2017 by JJay]




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[*] posted on 30-3-2017 at 23:32


While boiling down a solution of pentanoic acid in dichloromethane it boiled over, onto the hotter parts of the hot plate. This was hot enough to boil the acid and form clouds of pentanoic acid vapour, and these were awful, like burning feet.

So in summary I lost lots of acid and got to experience the horror of gaseous pentanoic acid




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[*] posted on 30-3-2017 at 23:38


Butanoic acid is like last meal revisited. What does its penty cousin smell like? At high concentraion and hot, I can imagine it was not pleasant.
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[*] posted on 30-3-2017 at 23:43


Quote: Originally posted by NitratedKittens  
While boiling down a solution of pentanoic acid in dichloromethane it boiled over, onto the hotter parts of the hot plate. This was hot enough to boil the acid and form clouds of pentanoic acid vapour, and these were awful, like burning feet.



just curious as to how you recognise the smell of burning feet :o




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[*] posted on 30-3-2017 at 23:55


Quote: Originally posted by Sulaiman  
just curious as to how you recognise the smell of burning feet :o

Being possessed of a healthy, active imagination, I'd warrant. :P

[Edited on 31-3-2017 by G-Coupled]
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[*] posted on 31-3-2017 at 11:34


>ITT: When Chemistry Goes Wrong
>40% HF
:o:o:o



Quote: Originally posted by Sulaiman  


just curious as to how you recognise the smell of burning feet :o


The only thing worse than recognizing the smell of burning feet.... is not recognizing the smell of burning feet. :o:o:o


Quote:

In another case, a young American airman was injured in a mock duel with another serviceman, when a miniature fencing foil was plunged into his right nostril, puncturing a small part of his limbic system immediately above. This resulted in a severe impairment of memory... a wide range o of perceptual and intellectual abilities was unaffected. His memory impairment was particularly noticeable with verbal material. In addition, the accident seems to have rendered him both impotent and unresponsive to pain. He once walked barefoot on the sun-heated metal deck of a cruise ship, without realizing that his feet were being badly burned until his fellow passengers complained of the uncomfortable odor of charring flesh. On his own, he was aware of neither the pain nor the smell.

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[*] posted on 1-4-2017 at 04:12


I got a new box of conical flasks from school on friday (last day of term), the often sell off things cheap this time of year. And we can buy glassware at any time at cost price :D.

So opened box of flasks and grabbed one, set on work bench and poured roughly 100ml HCl (36%) into it. Pick the flask up by the neck to carry over to my temp fume hood (yes should have poured the acid in the hood), and around 3/4 of the flask just separated! I was left holding the neck and some of the sides.

They use Duran or Pyrex and being a school no Chinese rubbish. but having to clear up 100ml of HCl all over the floor with glass shards, and just a simple mask..... Not fun at all. I dumped my bag of sodium carbonate on it first.

On reviewing it all later, I still cant get over the number of noob mistakes I made! I should be well past some of them by now :(.


1) new glassware, not washed first and not filled and checked for cracks etc.

2) Pouring 36% HCl away from the fume hood, just stupid and lazy.

3) Not having anything to neutralize at hand (I had to go to next room to get my carbonate), again really stupid.

4) Not having an adequate mask.........One reason I built the temp fume cupboard, so why dont I use it more!


Checked the other flasks and all have cracks in, I will get the money back, but more disappointed that I still do the really stupid and simple errors.

Like making my temp cupboard with sink in!! Then not connecting the waste of the sink up!! Lucky I discovered that while washing out a flask of acetic acid (10%).
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[*] posted on 1-4-2017 at 04:59


I'm great full for the simpler mistakes, it reminds us to never be complacent.

I thermal cycle all my new glass wear as well, after a good washing I flame dry it till it is hot to the point you feel it radiating, then once cooled to room temp in the freezer it goes.

Better to break it when it isn't full of 300c H2SO4 or other nasty compounds!
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[*] posted on 1-4-2017 at 05:48


Quote: Originally posted by XeonTheMGPony  
I'm great full for the simpler mistakes, it reminds us to never be complacent.

I thermal cycle all my new glass wear as well, after a good washing I flame dry it till it is hot to the point you feel it radiating, then once cooled to room temp in the freezer it goes.

Better to break it when it isn't full of 300c H2SO4 or other nasty compounds!


Silly question.....Isnt there a chance that it would break more easily on a second cycle? Like when you first use for real? Obviously that would only happen if you were boiling sulphuric acid or such! :D

Sounds like a good idea though, Being lazy and having a hatred of washing up dosnt help me. I am waiting for my mum to buy a new dishwasher.......... Happy day's when I bag the old one :D.
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[*] posted on 1-4-2017 at 05:54


This morning I was arrested for trying to steal a keg of methylamine for producing industrial quantities of MDMA for sale on the black market :o





Ok, actually that never happened. April Fool's!




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[*] posted on 1-4-2017 at 06:04


Quote: Originally posted by NEMO-Chemistry  

Silly question.....Isn't there a chance that it would break more easily on a second cycle? Like when you first use for real? Obviously that would only happen if you were boiling sulphuric acid or such! :D

Sounds like a good idea though, Being lazy and having a hatred of washing up dosnt help me. I am waiting for my mum to buy a new dishwasher.......... Happy day's when I bag the old one :D.


That's the idea, if it doesn't fail during the thermal cycling it isn't going to!

You can't control if it will suddenly fail but you can chose when apx! Weak glass will not handle a full thermal cycle with out cracking or some thing but well don glass doesn't even notice it.

I rather any thing breaks while it is clean of toxic or hazardous substances on it. I am a distilaholic, I distill all my solvents as I like clean pure materials to work with, saved me allot of head aches over the years.

So a small crack when distilling acetone = burny death, and well that kind of sods up the rest of your week!

Clean glass wear is critical if you want shit to go the way you want it too, due to bad water I have to do the first wash (Soap and water) then rinse with distilled water with a bit of HCL in it to remove the carbonates from the tap water, then a final distilled water rinse!

If I need a fast turn around I rinse it with methanol that gets dumped into the wet methanol jug to be later dried for reuse, then oven dry the glass wear.
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[*] posted on 1-4-2017 at 10:03


Quote: Originally posted by JJay  
This morning I was arrested for trying to steal a keg of methylamine for producing industrial quantities of MDMA for sale on the black market :o





Ok, actually that never happened. April Fool's!


So you did steal the keg? but you didnt get arrested for it? :D.


@ Xeon

I need to get some of the lazy arse out of me! TBH if I am going to get anywhere I need to up my game, my lab is a mess and my lab book a joke :(. I tell myself I dont have time, truth is I cant be arsed most the time to clean up. That is likely to bite me hard one day......

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[*] posted on 1-4-2017 at 11:47


cleanliness prevents burny fireness! Lab book? Whats that? lol I was all ways terrible at paper work or keeping it.

But ya keeping things clean keeps you from getting poisoned or fires starting
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[*] posted on 1-4-2017 at 12:06


Why steal methylamine anyway, nitromethane isn't exactly difficult to come by, and dissolving metal reductions (acidic type rather than Birch-like) of nitromethane can reduce the nitro group to the amine. There are an awful lot of such aliphatic nitro reduction procedures around
considering both the usefulness of lower primary alkylamines, and the great utility of the Knoevanagel condensation in producing nitroalkenes from aldehydes, this kind of nitroaldol is pretty popular with the Shulgin-fanclub type chemist crowd and invariably that nitro group is going to end up reduced to the primary amine or possibly hydroxylamine.

As for cleanliness preventing burneyness..

It does usually...not always. Had a random patch of burning lawn the other day and I really don't have a clue what could have caused it.

I'm going to invest in a new set of stainless keck clips and electroplate them in something extremely resistant, such as Ir, for this kind of chemistry. Even wrapping all joints with teflon tape and greasing the clips, the only one that actually survived more than a few hours was the one near the similarly treated flask generating the Cl2. Cl2 is corrosive enough, but iodine monochloride is just plain vicious. I think some perfluorocarbon grease is called for too. The dow-corning high vac grease suffices as a temporary measure, but it gets turned to something like cement after somewhere up to 12 hours or so (I wasn't there observing so I'm not sure how long)

Interestingly enough it didn't ignite fine magnesium dust, or 30 micron Al dust. Have yet to try nickel or copper. Doesn't ignite sulfur in the solid state, haven't yet tried it on powdered sulfur. One drop on (red) phosphorus ignited the moment the two contacted, and had more ICl been dripped on to the phosphorus sample I haven't any doubt it would have been extremely violent (these tests were all done on the scale of 100s of mg or so, a few spatulas full of each test reagent when examining the oxidizing power of ICl)

The Mg was actually difficult to ignite with an external flame, but the aluminium allowed itself (again, on this microscale, I wouldn't try it with large quantities for obvious reasons) to soak in the ICl, and on applying a flame, immediately flared white hot leading behind a white glowing 'coal', that was almost certainly anhydrous AlCl3 or AlI3. (does aluminium form poly(tri)halides of the nature AlHn1/2-Hn1/2 where H=two or more different halogen atoms?)


Still not quite sure what, or how it came to happen, but the night after the oxidizing powers of the ICl were tested, some 12 hours later, in an area situated a LARGE distance from the site of the tests, which involved at most a few drops at a time of the iodine monochloride, and any residue put to the flame of a blowtorch, there was an odd, smoking liquefied hole in what used to be the dirt of what used to be the lawn. ICl hydrolyzes very quickly on contact with H2O and isn't air-stable either, and is apparently somewhat unstable towards light. On adding 1 drop to a container of water, a puff of Cl2 is instantly apparent plus the iodine content being released, more or less on contact.

So I'm actually quite puzzled by what reduced that section of lawn and soil and stones to a puddle of something black, oozing and gooey-slimy looking, giving off (suddenly, during the day, it just started up giving off smoke according to my old man and hadn't been there all day doing it)

ICl would have been the first suspect, but for the fact that so little was ever taken from the bottle, a few drops, and none of it was within maybe 6-8 meters give or take, of where this black smoking hole appeared. And the fact that any ICl would have decomposed and vaporized, dissipating into the air over a timespan of 12 hours or so.

The only other thing possible would be either PI3, which again probably wouldn't hang around a dewy morning for hours, and in any case, the RP igniting would have vaporized it completely. Sulfur halides after testing on a small (thumbnail-sized) piece of solid sulfur...again, the remains of that were cleaned up with a blowtorch and were many meters away from the site of testing. The actual synthesis of the ICl itself is contained in a closed system, with the only exit being into a suckback trap exiting into a vessel containing saturated sodium carbonate solution. And its at completely the other end of the house. Cl2 wouldn't settle like that, and it would have bleached the surrounding area, if there had theoretically been a large scale release of chlorine gas, going from accounts dating back from WWII of the gas warfare in the trenches, vegetation bleaching in the gas clouds, rather than forming a bubbling, smoking black slime, and I can't see I2 liquefying dirt and gravel, leaving a smoking crater behind.

There were other burns nearby, from phosphorus, after an alembic cracked and decided to vent WP over the lawn, but again, that isn't capable of lying dormant for a month or two or three and suddenly reigniting.

Not even sure its something I DID, given the circumstances.


[Edited on 1-4-2017 by tsathoggua1]
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[*] posted on 3-4-2017 at 03:46


nitromethane is extremely hard to get in the UK. You are allowed upto 30% if its in radio controlled model fuels. But that is very expensive to buy.
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[*] posted on 3-4-2017 at 04:21


Seriously, though, I would be rather disturbed if my lawn spontaneously caught fire for no reason. Then again, I would probably also be disturbed if a black goo of unknown composition were seeping out of it in a puddle.





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[*] posted on 3-4-2017 at 04:39


If you live in Europe very well could be a WW1 era chemical weapon IE a mustard agent that has been decomposed.

I'd be very cautious around it and alert hazmat.
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[*] posted on 3-4-2017 at 06:34


Quote: Originally posted by j_sum1  
Butanoic acid is like last meal revisited. What does its penty cousin smell like? At high concentraion and hot, I can imagine it was not pleasant.

Its not pleasant at high temps, at normal temperatures it literally smells like essence of stinky feet.




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[*] posted on 3-4-2017 at 13:00


I VERY much doubt that a couple of inches of lawn would spontaneously start oozing WWII leftover sulfur mustard.

The lawn didn't actually catch FIRE, it just sat there, liquefying into black, virulent looking and behaving black slime, same consistency and color of that which comes from the deliquescence of shaggy ink-cap mushrooms (Coprinus comatus), only whatever it was, caused the lawn to hiss and give off some awful smelling, acrid, choking smoke.

I am pretty sure it CAN'T have been the iodine monochloride I'd been buggering about with, since that was done 10-12 hours previously, and all remains were dealt with by means of, whilst wearing gas mask, blast shield, goggles, elbow-length gloves etc, not only confining samples to a piece of glass or stone, but once reacted, or in the case of Mg, to encourage rxn, holding a blowtorch on full blast centimeters away from the sample, and in all cases a few DROPS of ICl were employed with spatula fulls of all tested chemicals save sulfur, of which a small nugget was chipped off one of my rolls of sulfur and ICl dripped onto it from a pipette. A blowtorch was again employed by way of cleanup.

The ICl synth setup was in the garden, but again a considerable distance from the suddenly smoking, liquefied section of the dirt below the lawn. And its a closed system, under pressure of chlorine gas, enough pressure to make a loud 'whoosh' sound if the system is opened at the Cl2 generator end. Its holding its pressure for days, and under additional pressure of argon to drive the Cl2 through the columb of iodine.

Question-I've heard reference to IBr5. Does iodine form a pentachloride? if a pentabromide and higher fluorides are extant, I see no reason why ICl5 should not exist. Does it exist and if so what are its properties? I imagine it would be a most potent oxidizer if it does exist, ICl is prety snappy when it comes to burning things.

The only other thing I can think of would be the phosphorus or sulfur tests. The red P ignited instantly upon contact with ICl (a single drop caused a large and bright flare the instant it touched the phosphorus) or the sulfur test, no flames, actually very difficult to ignite that piece of sulfur, although I did eventually get it to burn, slowly and calmly after taking to it my blowlamp on its maximum gas flow rate. Again these tests were done in sequence, less than minutes between them, and this whatever the hell it was quite literally turned not just the grass, but the soil and stones below it to black, smoking ooze, and it did so relatively suddenly, hours after any fucking with a few drops of ICl. The main bottle of iodine monochloride is intact and resists it just fine, it is standing in a closed, lightless cupboard that is dedicated mainly for storage of strong acids.

And I didn't think that iodine monochloride would be a strong enough oxidizer to liquefy stone and turn it to smoking goo.


As for butyric acid, its not stinky feet. That is valeric and isovaleric acids. Butyric acid smells like refined, distilled eau de barf. Believe you me, I know. I've worked with its anhydride a fair bit (n-butyric anhydride) and even my old man, no chemist, now recognizes that stench. Propionic acid smells a bit rancid, for some reason I think 'goat-ey' when I smell propionic acid. Butyric acid smells like the result of a sexual advance from Theresa May towards any sane individual possessed of the sense of sight.

Valeric (pentanoic) and isovaleric acids are the ones that reek of cheesy feet. Butyric acid isn't pleasant at any temperature, it just smells like puke threw up, ate its own vomit and washed it down with a cup of cold sick. The anhydride doesn't smell so noxious as the acid, but of course it hydrolyzes easily and if one can detect its smell (the anhydride smells flatter, thinner, slightly vomit-like but not nearly so strongly, and it smells of a quite different shape, hard to describe. Smells a lot thicker than propionyl chloride.None of the three feel like they have any color to their respective stinks though.

Again..hard to describe...synaesthetic senses probably don't translate well at all.
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[*] posted on 3-4-2017 at 13:02


As for nitromethane, I've never encountered the racing fuel, looked for it but never found anywhere that sold it. But I've never found NM or nitroethane difficult to buy in the untainted form. Although I haven't actually currently GOT any NM, I do have a liter of nitroethane sitting on the lab shelves :)

And as for the corrosive slime pool, it wasn't of vast size, a few inches in diameter, it smoked for a few hours and then kind of died off, leaving behind a puddle of soil and stones in black, oily looking, extremely acrid stinking bubbling glorp form. I really haven't the foggiest what it could have been. I haven't buried anything in the garden, and even less have I ever buried anything that might burst open and release something capable of liquefying stone.

Thats the kind of behavior I'd expect from the likes of chlorine trifluoride, ClF5 etc. but not the iodine interhalogens, save maybe the fluorides. And I've never MADE any iodine fluorides. Only the chlorides. The bromides of iodine, and chlorides of bromine are next on my list, as well as more chromyl chloride, for an etard rxn. (the CrO2Cl2. Fun to make too) the interhalogens will see their being put to good use, although my primary motivation for synthesizing them is out of pure scientific interest.

The 'because I can' kind of reason:) ICl3 is going to be next, will dissolve the leftovers from my ICl synth in pentane, or liquefied butane kept on a cryo bath, then bubble in chlorine in excess and finally evap off the alkane solvent to hopefully leave behind ICl3.

I really do want to know though if ICl5 or higher chlorides exist. AFAIK iodine goes up to a heptavalent oxidation state with fluorine, but the ionic radius of fluorine is rather small. So it might well differ for the other halogens being much bulkier in the case especially of E.g bromine. So steric effects could come into play. But chlorine? can chlorine form iodine tetra-, penta-, hexa- or heptachloride interhalogens?

[Edited on 3-4-2017 by tsathoggua1]

[Edited on 3-4-2017 by tsathoggua1]
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[*] posted on 3-4-2017 at 16:56


I tried to make nitric acid with a very bad setup. I used ammonium nitrate (by the way I hate ammonia because of this and the smell) and I heated it up too quickly, leading it to break down and fill my garage with laughing gas. It even made my voice slightly deeper.
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[*] posted on 9-4-2017 at 07:40


Quote: Originally posted by tsathoggua1  
As for nitromethane, I've never encountered the racing fuel, looked for it but never found anywhere that sold it. But I've never found NM or nitroethane difficult to buy in the untainted form.


In Poland, only a few years ago it was possible to buy straight nitromethane in RC model shops - intended for making your own RC fuel mixes. Roughly $100 for 5L, IIRC.

Now, because of increasingly B.S. EU regulations, it's still available - but NOT to individuals (regulated as an explosive precursor).
The only viable source now is in premixed RC model fuels, up to 30% nitromethane content, roughly $40 per 5L of such mix.
The remainder is mostly methanol, some lubricating oil, and small amounts of (unknown, proprietary) combustion improvers.

EDIT: Damn it all! On top of all this, methanol is now in the same legal category as eg. HCl or conc. H2SO4: still available to individuals in reasonable quantities, but requires filling out a bunch of stupid PAPERWORK.
Guess how I found that out... serves me right for not reading the blasted fine print!

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As for my screwups - I can recount a very simple, and stupid (but fortunately harmless) one right off the bat:
During my first stainless steel electropolishing tests, a few months ago, the recipe called for conc. phosphoric acid, ethylene glycol, and water, in roughly equal proportions.
I had the acid, but not the glycol (in pure form).

Then, a "bright" idea: I have a few L of car radiator antifreeze in my shed - and that's usually roughly 50% glycol in water, with a small amount of corrosion inhibitors.
And since this was some cheap crap, it's likely to have very little of the inhibitors (none at all, even?).

So, in goes the acid, and the antifreeze, in 1:2 proportions.
A good few hours were wasted in fiddling with various values of current density, to try and get a good result.
To make a long story short - this was totally, utterly useless for any sort of electropolishing.
It did, however, make the metal surface look a bit like a very scaled down surface of the Moon, complete with deep craters, "sandy" appearance, and all that. Not the desired effect in this case, though.

Fast forward a few months - I bought some real reagent-grade ethylene glycol, and tried this again with an otherwise identical setup - and to absolutely nobody's surprise, it worked OK. (later I refined the recipe a bit, but that's another story)

So, either that antifreeze contained no glycol (something else instead to depress the freezing point?), or the corrosion inhibitors which it (should have) contained somehow "poisoned" the electropolishing process.

Moral of the story: never assume that an OTC product contains a particular ingredient, or a specific mixture of ingredients - especially if it's not stated on the label.
Especially in recent times, what with things such as acetone-free acetone, and the like.

[Edited on 10-4-2017 by The Mad Plater]




Current chemistry WIP:
1. Mn phosphating of carbon steels:
- the phosphating step by itself works perfectly fine;
- currently working on surface prep & activation.
2. Zn phosphating of carbon steels:
- on backburner ATM;
- current status: brand new bath concentrate is ready for first phosphating tests!
3. Electroless nickel plating (>10% phosphorus content):
- on double backburner ATM;
- initial results (on carbon steel) VERY promising;
- plating on aluminium needs a lot more R&D (surface prep - zincating).
4. Electropolishing of stainless steels:
- IT WORKS! At least "well enough" for now;
- the process parameters could use a bit more refinement.
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tsathoggua1
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[*] posted on 11-4-2017 at 12:23


Lets just say, I am thankful for the full-face shield I wear now over my goggles, after an ampoule of white phosphorus broke whilst being heat-sealed, and the WP jetted out of the neck as the amp shattered. Made quite a mess of a wooden cupboard though and filllled a room with copious P2O5 smoke and a gout of intense fire.

No harm done though thankfully, other than a bit of crisped up and shrivelled burnt hair, with the accompanying stench of seared proteins, because my hair is longer than the longest available face shields on sale I could find. Only cosmetic damage, and that, some hair singeing aside, was to a cupboard not to me.

And some damage to a small carbon crucible, when it was being used as an anode during electrolysis of a melt of caustic potash and NaOH. They fare well enough against NaOH alone, or when used as cathode, but when they are used to form the anode of an electrolytic circuit they are badly attacked by the molten caustic, especially when having to initiate melting by means of striking a pilot arc.
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