That stuff will dissolve the finger and arm joints! - Many a Semiconductor type has rough or scratchy joints. A bit painful. Glad I heard and read the docs long before the hasmat stuff became popular or mandatory.
It is used to dissolve glass or silicon.. And other uses.
Martin
On Sat, 5 Mar 2005 15:04:41 -0700, "Don D." vaguely proposed a theory ......and in reply I say!:
remove ns from my header address to reply via email
You are fate muriatic acid. BUT check out "electrolytic derusting".
or start here
I don't know much about alodine/yne, but HCl is only going to etch Al, quite vigorously, releasing hydrogen gas. A 1/4 dilution will slow it but not too much AFAIK.
Tim
-- "California is the breakfast state: fruits, nuts and flakes." Website:
Fun stuff, eh? :-o Interesting tidbit: although fluorine is the most active cation, hydrofluoric acid is not the strongest acid, because though the gas is quite soluble in water, it doesn't fully ionize (contrast to HCl or HBr). That prize goes to a flurosulfuric acid, I think?
While we're on the morbid topic of poisons, what do you know of the dangers of nickel carbonyl?
Which reminds me, what's the most dangerous, in terms of LD50 quantity, non-biological (i.e., not a virus or something) chemical? Anyone? I know Ni(CO)5 is up there, with HgCl(2) too. Anything else?
Tim
Not a problem with HCl, the solution isn't particularly active with water. Sulfuric, however, is quite a water magnet and should always be added as mentioned.
Tim
-- "California is the breakfast state: fruits, nuts and flakes." Website:
On Sun, 06 Mar 2005 04:53:38 GMT, the inscrutable "Joe" spake:
Hydrofluoric acid is supposed to be the hollow-point slug of acids. The little drip goes on the skin in a small area and comes out inches larger on the other side. That got my attention when I heard it eons ago.
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Don, That stuff is shipped in a concentrated form because it is less reactive. Mix that stuff with water and that stuff is very agressive. It will dissolve aluminum instantly as well as glass and concrete. The fumes are super corrosive. You must do this outside. It will eat holes instantly through your clothes and then your skin. You must wear full protective clothing and not all types of rubber gloves provide protection. I use the stuff in motorcycle fuel tanks. You apply the acid in the tank for periods measured in seconds not minutes. You must always rinse with water several times and then use bicarbonate of soda to nuetralize. Steve
Back when I was in school, I once pulled the stopper on a retort of boiling nitric acid. I "invented" nitro-thumbnail. It didn't do any permanent damage, but my fingers stayed yellow for a week. The teacher congratulated me on having "discovered" the test for protein...
Jerry
???
Me and a buddy of mine used extensive amounts of nitric in recovering silver from photographic film - Mainly old X-rays and printer's films.
The operation was pretty simple: Umpty-odd gallons of nitric acid (from flasks labeled "90 degree baum") in rubbermaid garbage cans. Soak filmstock in it until the gelatin became liquid enough to scrape off the backing material, scrape it off, and discard the backing. Lather/rinse/repeat until the sludge in the bottom of the garbage cans got good and deep, let settle for a few days, rack off most of the acid above the sludge to another can for re-use, then process the sludge.
As part of this operation, both of us routinely goggled up and went into the garbage cans with bare skin almost armpit deep to pull the old films and scrape what could be scraped. Worst effect noted: yellowing of the skin and fingernails anywhere the acid had made contact. Kinda like that "suntan in a can" stuff, but more yellowish than tan in color. Granted, after a "fishing expedition" (and often during it), we hosed off quite thoroughly, so we were rarely "leaving it sit to work" for very long.
About the only time either of us encountered any kind of discomfort was if we caught a whiff of the fumes, and that was more on the lines of "Yeesh! this stuff will 'bout rip your sinuses out, won't it?" than any sort of real "hazard".
That was the thing we were both most careful of - We'd go almost armpit deep into the cans with bare hide, but neither one of us wanted to be in the same room with the stuff, let alone actually spalshing around in it, without goggles.
I soaked about 10 horseshoes last night to see what it does and it did remove the rust but they still need light wire wheeling to remove the light residue and the horse s$%#, but it will save a lot of time on the wheel. and the occasional flying horse shoes when the wheel gets the best of me... I am using it about 25/75 and would like to know how do I neutralize the acid when I am done using it before disposal (baking soda?) and or what is the shelf life if in this stage if I do not dispose of it.
Thank you all for your input, This is going to save me a lot of time Don D.
Dump in baking soda, crushed drywall, or gypsum chips/powder until it stops "fizzing". You end up with what amounts to a container of saltwater. (And might actually end up with some salt precipitating out of the solution if you use baking soda - "Snow melter" (Calcium chloride) will be the result if you use drywall/gypsum chips).
Shelf life is going to be short unless you can seal the container airtight. On the order of days, I'd estimate.
Ni(CO)4 itym.
Starting with sodium cyanide, at a LD-50 of 150 mg/kg:
At 37 mg/kg mercuric chloride is not far off.
Carbon monoxide would be in here somewhere, maybe 10 mg/kg.
Then comes hydrogen cyanide, surprisingly toxic at about 1 mg/kg.
Nickel carbonyl and sodium fluoroacetate fit in next, at about 0.5 mg/kg.
The nerve agents are next, at about 0.1 mg/kg, and one of them, possibly VX, might be considered the non-biological champ.
However Saxitoxin, originally a toxin from algae, has been made synthetically, and is probably the non-protein champion killer, at 0.01 mg/kg.
Doesn't compare with Clostridium Botulinum neurotoxin though, which at 200 pg/kg (that's _pico_grams per kilo) is about 50,000 times more deadly.
These are all chemicals btw, and in no sense are they alive. The lethal "dose" of some bacteria or viruses or prions may be lower.
Note that all these LD-50 figures (the amount needed to kill 50% of the recipients) are really gross approximations, many aren't know that accurately. Note also they are for acute toxicity and a quick kill only - some of these toxins will have long-lasting effects, eg they may be carcinogenic, or do other damage which can kill later, and some will not.
I have also massaged them a bit in an attempt to compare like with like, but that's a bit difficult when eg some are absorbed through the skin and some are harmless on skin, some will only kill at that level if injected, some are gasses, and some are solids!
--Be safe; chuck 'em in a vibratory tumbler and come back in an hour.
Yep! Unless you enjoy excitement.
Harold
I guarantee you, there's now way in hell you'd have had your hands in the solution if it was full strength. Just like the fumes were tough on your lungs and eyes, so it would have been on your skin. When I was in the learning phase of refining precious metals, I did a lot of testing of metals to identify them, using a dropping bottle of nitric. I lost a fair amount of skin, although not much at any one time, thanks to the small amount of acid in question. I didn't enjoy the yellow, peeling skin. Didn't take long until I learned to wear gloves-----always.
Harold
Is a major component of wood bleach and rust stain remover.
Both (diluting sulfuric and hydrochloric) are exothermic. Both should be done acid -> water. Granted the sulfuric is much more so.
Jim
That's the under statement of the year!! I completely emptied an evaporating dish once simply by adding sulfuric acid too rapidly. Sulfuric acid is used in gold refining to eliminate lead, which is death on the qualities of gold. The evolution of steam was instantaneous the moment I stirred the solution. Luckily, it was in a fume hood and I was wearing gloves.
I used HCL for years and never worried about adding it to water. Even using reagent grade, the heat evolved was so minimal that it was barely enough to raise the temperature of the solution enough to be noticeable. You can add water to reagent grade HCL with no consequences.
Still, in order to prevent accidents, it's a great idea to try to always pour acid into water, not the other way around. It builds good and safe habits.
Harold
I have been checking up on each batch in the 5 gal.about bucket about half full for about 2 - 4 hrs and pull out the ones that have been cleaned and most are done by 6 hrs. I am on my second batch now and as they get pulled out I put them in a water bath and soak for a short then put them in a milk crate and hose them off for the last cleaning. When they dry off, I will wire wheel them off and shine them up at that point.
Listening to all of you talking about all the other acids already tells me not to mess with any of them.
OT: What was the acid that Jeffery Dommer used to dissolve his victims. I would think it could have been one of the ones mentioned in this posting from what I been reading.
Don D.
Er, sulfate (gypsum is calcium sulfate) is more stable than chloride; hydrogen chloride is distilled off when concentrated sulfuric acid is added to salt, no? Calcium sulfate is mostly insoluble, also.
Limestone works well though, if slowly. Soda is good and quick, especially if you make a solution.
Tim
-- "California is the breakfast state: fruits, nuts and flakes." Website:
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