IRIDIUM processing ?
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Metallic iridium flakes from crashed ore or concentrated from sands can be quantitatively dissolved only in molten salts. And this is very long process always includes platinum. Almost impossible outside of specialized lab to divide clear 99,99%Ir and clear Pt 99,99%. And usually there is no practical need for this. Commonly used nature alloy of 90% of Pt and 10% of Ir (approximately)
Just what it sounds like - a salt that has been heated up until it melts. Most salts have fairly high melting points, but often within range of an air-fueled furnace. For instance, sodium chloride will melt at 801 C:
Sounds like a recipe for blindness. Usually alluvial iridium (not from ore, but from placer deposits) is always associated with osmium.
Be warned!
Be warned!
kurtak
Well-known member
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What kind of lab test report?
I will just explain what Lou correctly pointed out with his post.
Iridium is commonly associated with osmium in the ores, and even ruthenium can be there, altough less likely.
When osmium is oxidized in strong oxidizing conditions - it converts to octavalent state - osmium tetroxide - OsO4 - which has very low boiling point and EVAPORATES from the melt or leach. Osmium tetroxide is extremely toxic compound, even in well setup industry, all manufacturers avoid its use (as catalyst for organic synthesis). It has very nasty feature - being very violent oxidant - to be reduced upon contact with tissue to lower valence osmium compounds - which are black and does not degrade in body on any circumstances. So vapors of OsO4 hit your retina in the eye, deposit there and turn black. Irreversibly. Making you blind forever. No cure.
Same story with ruthenium - which is actually used to visualize the fingerprints - vapors of RuO4 will contact grease from fingerprints and reduce themselves - turning black.
Very true
Although I’d believe it to be true and agree, all this is true in theory and no evidence is present in practical cases except for one as this article claims, where a lady aged 32 spilled 9ml of osmiium over her self, skin & eyes, and after some symptoms she managed to recover.
https://onlinelibrary.wiley.com/doi/full/10.1111/bcpt.13450
https://onlinelibrary.wiley.com/doi/full/10.1111/bcpt.13450
Osmium poisoning is in fact very rare, but the most important reason for that is that the Osmium itself is very rare.
The number of persons in contact with Osmium yearly is exceedingly small.
Additionally most of these are educated enough to treat it with respect.
Most of the cases of actual Osmium poisoning will probably come from the early days,
when there was no or little safety protocols and little information to have.
And then there is the odd refiner that don't have the full oversight or information due to lack of tests.
One of the risks with OsO4 is that it is accumulative so if you get a bit now and then,
you might not even notice and your doctor would probably not know what is causing your eyesight or liver to fail gradually.
Ending up with a completely wrong diagnose.
In the end it comes down to knowing your feed stock/ore and the limitations of your skills and lab.
Even biggest guys in the organic chemistry industry refuse to allocate the facilities who work with osmium in synthesis to third world countries. They stopped to use it domestically completely (and trust me, replacing OsO4 as catalyst is sometimes impossible, and whole synthesis need to be completely re-established from scratch = immense money cost) and even refuse to use it abroad.
We used OsO4, or more specifically K2OsO4 precursor on many occasions throughout our syntheses in research. We stored the Os waste in classic 1L amber glassed bottles with standard plastic screw caps, which were PE from inside. After several weeks, OsO4 MANAGED TO STAIN POLYETHYLENE BLACK. One of the most unreactive substances.
This is not about one time events. I wish Lou had more time to talk about "osmium and ruthenium issue" in greater detail, as he certainly has immense first-hand experience with it, as professional PGM refiner.
If you will be ever processing Os containing material in oxidizing conditions, you will contaminate your workplace with Os inevitably - if you does not plan everything and scrub everything. Any leakage, low-grade fume extraction and fumehoods, exhaust re-suction to the lab... Will eventually expose you and your workers to very dangerous heavy metal. Slowly and steadily it find it´s way into your body and never leave.
Very similarly to platinosis and related PGM toxicity. Many people here laugh at it saying they work with PGMs and they are strong and healthy, while washing beakers after use with bare hands. But truth is, chemistry is unforgiving and it always does what it is supposed to - no matter what your believes are. Some are more susceptible to the effects - like I am.
I am well aware of the fact I am highly sensitive to PGM compounds. After year or two, despite wearing all PPE gear, and working diligently in fumehood - I encounter mild skin rash and itchyness after working larger batches of PGMs. From barely noticeable events, steadily and slowly to redness on the rim of my gloves, mild sore throat feeling and headache. All of these events can be very effectively tracked down to PGMs - with gold or silver, that never happened once.
One event happened several months ago - fumehood I was working in (with multiple ozt batch of formate reduction of PGM feed - effervescence of CO2 create aerosols) apparently re-sucked some air back into the laboratory. Two other ones were switched off, and pressure relieved by back-sucking the exhaust air to minor extent also by recupering the fumes (as the vents were in few meters distance one from another) - from evolution of aerosols of the chloride PGM solution in 5L beaker. After an hour or so of work, I start to notice subtle sore throat effects and itchyness on my face. Luckily, I recognized quickly where the issue lies - by opening the bottle of borane-dimethylsulfide in the hood I was working in. Awful smelling chemical. This in matter of minute came back by the other two hoods and clearly stenched from them. I quickly powered them up and instructed my colleague how to properly shut down the operation, as I immediately needed to go out. Tjis was clear warning sign for me, and from then ongoing, I take great care of what and how I do next. Mitigating PGM refining to bare minimum and sticking to pyrometallurgical ways of cleaning as much as possible, obviating the creation of PGM salts. And even in the cases where I need to actually disslove and work with PGM compounds, I prefer reactions where no aerosols or dried powders are produced. Solutions are practically perfectly containable and manageable, but evaporation, formate reductions, zinc cementations... These are concerning now for me.
For now, I managed to find ways how to mitigate the now practically unmeasurable exposure to these unforgiving compounds. And as I really do like and enjoy refining, I am maybe closer than I want to be to quitting all PGM refining, due to altough subtle, but clearly rising concerns about my health - which is my top priority.
PGMAN, please listen to the warnings people are giving you. This is not a joke. We have lost members of the forum because they worked with platinum group metals. When I say we lost them, I mean they died! As in DEAD! One of them, freechemist, dealt with these metals as his profession, and it still KILLED HIM. He knew the dangers. He took precautions. And he's still gone. I miss Hans.
But you do you. If you feel that the results of your internet search are more valid than what our members have told you, we can't stop you from following your beliefs. I only ask one thing. Please protect everyone around you - those in you house, your neighbors, their pets and any other animals around you, and the folks who will be exposed when they have to clean up the mess you leave behind.
Dave
But you do you. If you feel that the results of your internet search are more valid than what our members have told you, we can't stop you from following your beliefs. I only ask one thing. Please protect everyone around you - those in you house, your neighbors, their pets and any other animals around you, and the folks who will be exposed when they have to clean up the mess you leave behind.
Dave
- Joined
- Jan 14, 2021
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It will be much more easier and cheaper to give it to a refinery that refine it. Most of them can buy it back from you or give you pack the metal.
I can PM you the report if you require and maybe you can guide me there on
