Osmium Tetraoxide

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fishaholic5

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Osmium.... Since it can form the volatile Tetraoxide by heating or reaction with acids, is there any way to minimise the amount of the Tetraoxide formed during processing or leaching ores and concentrates containing significant amounts of Osmium?

Cheers Wal
 
In medicinal use, osmium tetroxide is easily transformed to harmless osmium dioxide by glutaraldehyde. Probably formaldehyde also will do
 
Some experiments I've been doing over the last 12 months using bacteria have shown that they can selectively remove Osmium from concentrates and solutions at a particle size large enough to be gravity separated from the rest of the concentrate.

I'm not sure of the practicality of using this on a larger scale yet but it has allowed me to separate the bulk of the Osmium from an Ore I've been working on while retaining the bacteria to selectively remove Gold and Rhodium from the concentrate under a different set of conditions.

Cheers Wal
 
This group of experiments originally started to explore the role of bacteria in dropping metals from solution in enrichment zones.
I now believe that most if not all secondary enrichment zones are bacterially assisted other than alluvial deposits.
The same applies to primary deposition in hydrothermal deposits.

If the deposition zone is still active, the organisms can make recovery of metals quite difficult, with recovery rates being a fraction of what is available unless they are removed. Some have the ability to create alloys within an Ore or concentrate that is resistant to attack by that chemical method within a very short space of time
IMG_20210306_181038_4.jpg
Here I'm in the process of setting up a new culture tank for my earlier experiments on bacterial recovery from transport zones


Cheers Wal
 
Bacterias act by looking for food, or oxygen and in the dark. Can you express their expected role in your situation?
 
The organisms involved in my experiments can utilise any Carbon source, air, Nitrogen source and Sulfur source as food. They operate both aerobically and anaerobically.
Their activity relating to metals appears to be a protective mechanism where they can deposit the metals or use them to shield themselves or remove metals or compounds that are toxic to them.
In the case of Osmium the metal is removed from solution and turned into a blue crystal.
I'm now trying to grow the crystals to much larger sizes (>5mm) using a culture.
The previous experiments have yeilded Osmium grains to 2mm

In the Pod culture experiments the expectation was that they would remove the metals from solution.

Cheers Wal
 
Most of the experiments have been simply to see what the response is to different conditions.
This one is growing ore nodules from solution as a response to the addition of salt to the groundwater transport solution.
The pH is 7, salt concentration is 3.5g/L and the solution has been changed 4 times at one month intervals.
IMG_20210705_133141_1~2.jpg

What I am hoping to do is learn how to use them in both recovery and some refining stages and explore their role in precious metal deposition. I'm in a position where I have the freedom to just look at it all for interests sake without being hamstrung by any expectations.

Cheers Wal
 
If so, they possibly consume oxygen from OsO4 and most of all sulfur from pyrites which associate precious metals
 
This one may end up beeing interesting in the long run.

I understand you will keep most close to hearth,
at least for now.
But can you disclose the family of bacteria?
E coli, bacillus or so?
Have you mostly been working in neutral solutions?
I guess the ore will need to be finely divided like in all other recoveries.
So the important thing is if you can find conditions
that need no or less chemicals and have a reasonable recoverytime.
 
Lino1406 said:
If so, they possibly consume oxygen from OsO4 and most of all sulfur from pyrites which associate precious metals
Click to expand...

I think that's the case, the current experiment is to see how they react to a solution containing little but Osmic acid and no other added food source.
All of the deposition zones I have taken cultures from for this are from enrichment zones adjacent to the original Sulfide deposits and a few from the transport solutions themselves.

Cheers Wal
 
Yggdrasil said:
This one may end up beeing interesting in the long run.

I understand you will keep most close to hearth,
at least for now.
But can you disclose the family of bacteria?
E coli, bacillus or so?
Have you mostly been working in neutral solutions?
I guess the ore will need to be finely divided like in all other recoveries.
So the important thing is if you can find conditions
that need no or less chemicals and have a reasonable recoverytime.
Click to expand...

I've run experiments at everything between pH 1 and 14, in Chloride leaches, AR, Nitric, Sulfuric, Sodium Hydroxide and in salt solutions of varying strengths.
Temperatures have been between 20°C and 100°C
Particle size of the Ore has been 80% <200mesh.

I have no idea what the family of bacteria is or the genus or species but due to the range of conditions they can handle I'm thinking they are Archeans.
It is quite probable that there are a combination of organisms involved.
Recovery times range from days to weeks to recover metals from solution in 1000L pods. Separation of Osmium from a concentrate can be achieved in hours on a small scale, I haven't tried this in a Pod

Cheers Wal
 
How do you know if there are any microorganisms
in there at all?
The various extremophiles usually have only
one superpower.
Extreme:
Acid tolerance
Caustic tolerance
High temp or low temp
Toxins and so on.

But the more we learn the more we get surprised.
You should get a sample and send to some University
for genus typing.
Maybe there are colonies with different properties
in there.
How did you stumble upon these?
Regards Per-Ove
 
I am sure there are microorganisms involved through the responses and the visible formation of bacterial gels in response to food sources..
At this stage the identification of genus and species is less important to me than learning how to find them, culture them and use them.
2020071009543800 (2)~2.jpg
20200710095705474 (2)~2.jpg

This is what they do in an alkaline solution containing Gold, the bacterial gel is visible on parts of the mass they are creating.
Under these conditions it appears that they do not need to use the gold as a protective shell as they would in an acidic medium.

I stumbled upon them while researching enrichment zones. After realising that they interfered with the extraction of the metals from the ores I was working with and learning how to identify the bacterial gels in certain ores (combined with a lot of observation and experimentation. This has taken me over 6 years :lol: ) I decided to study them on a larger scale.

Cheers Wal
 

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