Reducing agents for PGMs

[Yggdrasil]

I am reading and studying research papers every day in my work. If I could decide, I always pick the old paper or letter first - reason being, it is less likely some kind of bs.
Lots of science published today is rubbish, just to make points to climb professional ladder. Irreplicable syntheses, manually corrected spectra, inflated yields, completely made-up results etc. As organic chemist I can relate to this very very much. Science has changed a lot.
Also, the experiment description is very thorough in old papers. Observations are pointed out, suggestions given, colours noted etc... Today, procedure is like - dissolve, stir, filter, wash, column chromatography...

There are exceptions. But trend is clear

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Designs of some old apparatus were very clever. Old folks were much more "practically skilled" in my opinion, realizing the problems and adapting their solutions with materials they had in hand. One of the most practical, and very old inventions, is aspirator vacuum pump. I use it pretty much all the time, as it allow one to suck corrosive vapors in without damaging the pump itself (glass ones are the best). They are subsequently neutralized in solution, dispersed and easily contained. I like it a lot.

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Lots of people do not realize how toxic barium is. Most commonly, people in refining will encounter barium as part of ceramic used for MLCCs manufacture - barium titanate. However, this is relatively safe as compound, unless you attemp to leach it with acid. Leachin MLCCs with HCL results in liqification of Ba as soluble BaCl2 - many folks avoiding pyrometallurgy will just dump the MLCCs straight to the acid and start boiling. This liberate quite a bit of barium, which then should be scavenged with sulfate afterwards. BaSO4 is practically harmless, altough I don´t know if it is still categorized as "hazardous waste".

Just last week I read a meta study where they had checked research since long time back (1900s or so, can't quite remember)
and the conclusion was quite clear, modern research added little to nothing to the knowledge, techniques and patents today.
The amount of recent papers and research was unprecedented, but added next to nothing in theoretical or practical results.

 

[lazersteve]

He probably tested the mother liquors with zinc or possibly KI for Pd and KCl for Pt followed by evaporation. That in conjunction with stannous testing will get you down to a few parts per million with concentrated solutions I would think. His methods I'm quite sure are inferior with respect to accuracy we can get today, but like you stated, they did very well considering what they had to work with including prior knowledge.

The guys back in those days were the pioneers of our fundamental understanding of PGMs. They were very meticulous and methodical...recording everything from temperatures to start and finish product weights of even wastes.

Like I said, I surprised they don't get more recognition from all of us today. We are all standing on the shoulders of giants.

Steve

 

[Yggdrasil]

He probably tested the mother liquors with zinc or possibly KI for Pd and KCl for Pt followed by evaporation. That in conjunction with stannous testing will get you down to a few parts per million with concentrated solutions I would think. His methods I'm quite sure are inferior with respect to accuracy we can get today, but like you stated, they did very well considering what they had to work with including prior knowledge.

The guys back in those days were the pioneers of our fundamental understanding of PGMs. They were very meticulous and methodical...recording everything from temperatures to start and finish product weights of even wastes.

Like I said, I surprised they don't get more recognition from all of us today. We are all standing on the shoulders of giants.

Steve

Hear, hear!
Sadly probably some forgotten as well.

 

[orvi]

Just last week I read a meta study where they had checked research since long time back (1900s or so, can't quite remember)
and the conclusion was quite clear, modern research added little to nothing to the knowledge, techniques and patents today.
The amount of recent papers and research was unprecedented, but added next to nothing in theoretical or practical results.

This is true, but not completely. It vary widely from field to field. In organic chemistry, we are now in completely different galaxy of knowledge then like 100 or even 20 years ago. Ammount of progress there is immense.
On the other hand, you are completely right about throughput of the research - lots of meaningless articles appear nowdays. It happen because most of the times, your quality (and in turn salary and extras) are measured by ammount of publications+citations. This does not necessarily mean your research is innovative and useful. It correlates OK, but not everywhere.

Another thing to consider is - in 1900s, in most scientific fields, there was like "empty desert", and very little was known at date. As mainly analytical methods and instruments capabilities exploded later after WW2, and then even more with arrival of first usable computers... Science in most of the fields experienced the fastest development ever seen in history. Then from like 2000s and ongoing, most low-hanging fruits were collected.

There are groundbreaking discoveries waiting to be uncovered, that is for sure - but statistically, scientists nowdays have lower chance of suceeding due to that very reason quite a bit was indeed discovered before.

And as frustration build up, your research is going south, sucess rate of validating your ambitious theories is as expected lower than say in the 60s... Generally, after year or two without sucessful publication, you are cut from funding quite drastically as young independent scientist - and that encourage "dirty" behaviour, falsifying data, making meaningless articles just to get that "tick" you published etc etc
Style of writing now vastly overrun the actual content quality. And unless you aren´t very reputable and respected scientist, acceptance of ambitious hypothesis and theories is very low - mainly if they deviate from the well known "mainstream" science.

My professor said it very clearly: "If Einstein was about to publish his general relativity theory today, he will have very hard time to even strike impact 2-3 with his article, not speaking about number of rejections which he will needed to go through. It is possible that in low impact journal, his groundbreaking work would be passed unnoticed".

 

[orvi]

He probably tested the mother liquors with zinc or possibly KI for Pd and KCl for Pt followed by evaporation. That in conjunction with stannous testing will get you down to a few parts per million with concentrated solutions I would think. His methods I'm quite sure are inferior with respect to accuracy we can get today, but like you stated, they did very well considering what they had to work with including prior knowledge.

The guys back in those days were the pioneers of our fundamental understanding of PGMs. They were very meticulous and methodical...recording everything from temperatures to start and finish product weights of even wastes.

Like I said, I surprised they don't get more recognition from all of us today. We are all standing on the shoulders of giants.

Steve

Basic analytics in his era were probably less specific, but for work - I think sufficient. Concentration of the solutions can get pretty accurate SnCl2 tests, and also PdI2 from evaporated and treated solutions can give you good gravimetric results. For what it´s worth.

To the meticulous and methodical approach - very true. I, as scientist, experience general refusal of the rich descriptions and thorough analytical approaches by today journals. Typically high impact journals. Which should provide "Rolls Royce" edge articles about current developments, lack detailed information about how it was all done. Too much questions, which arise while reproducing the work, remain unanswered.

I developed several new synthetic protocols, for which it is important to follow procedures thoroughly and pay attention to some "preparational" details. Such as for example dispersion of the melts into water and thorough mixing is necessary, or pH adjustment need to be very precise in order to get high precipitation yield of some ligands etc... I write the manuscript with rich and very practical procedure (after following which, you 120% get what I got, in specified yield and purity). Submit the manuscript - and THIS IS THE FIRST THING WHICH IS ISSUED BY EDITOR!! "Your discussion about procedures is too complex and unnecessarily exhaustive"... Rage level 999... I, who did this first time ever in the world, with obviously maximum knowledge of that particular transformation, am too exhaustive and unnecessarily complex... Yeah.

So you calm down, politely answer that these details are utterely necessary to achieve these transformations. Then they somewhat move on to other "issues", mainly with "English language structure", lacking novelty, not that novel methods... And after all, they reject you. So you downgrade to some lower impact journal, rewrite the whole article, submit and repeat this till you succeed somewhere. This consume unhealthy ammount of time, your energy and motivation to proceed further. All in all, your research, capable of immediately help the community to proceed with difficult transformations - gets burried in some impact 2 journal, you get minor citations and you are done

 

[butcher]

From what I understand, Robert Wilhelm Eberhard Bunsen lost an eye in a chemistry experiment where he had an explosion.
His fellow scientist which also worked on the spectroscope was wheelchair-bound (not sure why).

these scientists learned or improved upon the ideas, knowledge, and inventions of those with the same interest as those before them, they were very educated some with good schools, but mostly from their own interests study, and experimentation.

Not much has changed since the beginning of man, we have some improvements, upon those who have gone before us from which we can gain some knowledge, and then through our own study and trials we may be we will be able to improve upon it and grow in our knowledge and then share what we learn.
just like our forum learning and sharing with others interested in the subject.

I feel much of our old knowledge is forgotten (because it at the time was no longer needed we had "new better ways" or no need to make or do it that way "we have modern products mass made" or better tools or machines, so we lose much of that knowledge, hardly anyone made their own soap from frying their morning breakfast and cleaning out the wood stove, they could just buy a box or bar the daughter was no longer interested in the lye soap making process...


I enjoyed the study of the paper, the fusion is interesting although a bit complicated much is similar with respect to the methods we use with aqua regia (except in fusion processes) precipitations also were chemicals similar to what we use, and the generation of hydrogen gas in a Kipp apparatus like flask for gas generator or using a Dobereiners lamp ( the day's cigarette lighter or fire starter with it platinum screen to generate hydrogen gas and a flame) for his experiments was interesting but what got me was the amount of effort and time spent, the documentation was excellent, the idea of known at his time and his improvements to the processes of those who went before him, yes these men of old were giants in their field because they worked and studied hard for their education.


Thank You, Laser Steve
you gave me something to get me interested in again, or at least added to all the other interests I currently have now, thank you for sharing, I also thank you for being one of those giants of old, as long as you are still kicking keep at it .

 

[Platz]

I completley agree with all your points above, recent research articles are generally rehashing old work under the guise of some innovation which grants more funding. Anything that is trully an innovation and discovered during sponsored research is likely to be kept hidden for as long as possible.

 

[Ssofm]

Search for papers written around 1868 by Bunsen on the topic of separation of PGMs. He details the use of molten zinc as a recovery/collection method from raw ores followed by hydrogen gas reduction.
This is the same Bunsen that the famous "Bunsen Burner" is named from. Frankly I'm surprised I haven't seen his work mentioned more on the forum.

Steve

Hi my friend
AR is good for dissolve Pt-Pd-Au and remains(Ir-Os-Rh-Ru) didn’t dissolve. What is your method for dissolve and separate (Ir-Os-Rh-Ru)?

 

[Yggdrasil]

Hi my friend
AR is good for dissolve Pt-Pd-Au and remains(Ir-Os-Rh-Ru) didn’t dissolve. What is your method for dissolve and separate (Ir-Os-Rh-Ru)?

These are notoriously hard to dissolve.

To get you started.
Read the book Steve recommended or this one from Ghilchrist.
METHODS FOR THE SEPARATION OF PLATINUM, PALLADIUM,
RHODIUM, AND IRIDIUM FROM ONE ANOTHER
AND FOR THEIR GRAVIMETRIC DETERMINATION