# Platinum Refining slide show



## lazersteve

All,

Since I was off for Veterans Day today, I decided to take advantage of the free time and make a Platinum Slide show for the Forum...


Platinum Refining

Let me know what you think.

Here's a photo of the resulting 18.1 gram Platinum Bar:







The photo does the bar no justice. It's glaring to look at it is so shiny. I had to turn off the flash due to the glare.

Needless to say, I had a wonderful day today. 8)

Steve


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## OMG

Looks great. And fun too!


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## Shecker

Awesome Steve.

Randy in Gunnison


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## watlarry

Thats one pretty piece of metal.


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## Platdigger

Nice slide show Steve!

So, your starting material was roughly 94 percent pure?
Randy


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## lazersteve

Randy,

I think it was closer to 95% as I had a small fraction of material undissolved (0.4 g) and a even smaller amount stuck to the filter paper as orange powder.

Steve


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## butcher

fantastic  can't wait to get caught up on few bills, to get one of your video's, thanks


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## BigDallas

Hello everyone,

I am new to this, I thought the video by lazersteve was excellent. I had one question about the solution used. Does it have to be aqua regia for ammonium chloride to work or can you simply use a hydrochloric acid solution and then precipitate it with ammonium chloride. 

Thanks.

Dallas


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## g_axelsson

You need the aqua regia (AR) to dissolve the platinum. Pure hydrochloric will not affect the platinum.


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## BigDallas

Oh ok thanks, g_axelsson.

That is what I thought, but my main problem is that I have been encountering some difficulties finding some nitric acid here in the Czech Republic. I am trying to make some calls to some chemical and laboratory stores here. 

Thanks again. Dallas


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## g_axelsson

If you don't find a source you could search the forum for "poor mans AR" or read any of the topics on how to make your own nitric from sulphuric acid and nitrate.


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## aflacglobal

g_axelsson said:


> If you don't find a source you could search the forum for "poor mans AR" or read any of the topics on how to make your own nitric from sulphuric acid and nitrate.



Concentrate Nitric Acid ?
Chris,
Nothing appears wrong with yours a first glance, except in mine I’m not leaving any Hydrogen
behind as follows:
H2SO4 + 2 NaNO3 --> Na2SO4 + 2HNO3
The big difference in my recipie is the solubility of the sodium sulfate salt (as opposed to
sodium hydrogen sulfate you produce) and the fact that my equation yields twice the nitric
acid at a higher temperature ( no dry ice, just salted ice ).
I’ve run the numbers like you did and ended up with about 160 mL of 50% nitric (give or take
a few percent) for a single mole of 96% sulfuric and using 100mL H2O to dissolve the nitre.
I won’t bore everyone with the math, but here’s my summary (PM me to see all the factors I
used to derive this reaction):

Reaction:

-Bring 100 mL of Distilled Water in a 500 mL pyrex beaker to 100 C
-Add the Nitre of your choice (202 gm K / 170 gm Na) K= Potassium NA= Sodium
Stir until Nitre is completely dissolved, let cool below boiling-
SLOWLY add 56 mL conc (96%+) Sulfuric Acid to Hot Nitre solution while stirring, DON’T
allow the solution to boil!
-Allow solution to cool to room temp (DO NOT SKIP - VESSEL WILL SHATTER IF PUT ON ICE
WHILE HOT!!!)
-When vessel reaches room temp (25 °C) put the vessel in the freezer or on a salt water ice
bath
-Let stand until temperature of mixture reaches -5 °C
-Let stand at -5 °C until all percipitate settles
-Pour the COLD solution off into glass container with tightly sealed lid DO NOT POUR OFF ANY
OF THE SALT IN THE BOTTOM!!!
-Makes ~160 mL ~50% HNO3

This acid in turn can be used to make true AR with the standard 4:1 recipie (HCl:HNO3).
Steve:


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## qst42know

As a safety issue please highlight this portion of your procedure:

*-Stir until Nitre is completely dissolved, let cool below boiling *

The solution reacts violently if you don't let it cool a bit before adding the sulfuric. I had quite a time cleaning nitrate pudding off of my hot plate and work surface.  

A big, down right volcanic mess and no fun at all. Let it cool below boiling is a vital step you don't want to skip.


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## Strider

Hello...I was wondering...how much would a bar like that cost in jewlery stores? More than the same amount of gold?


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## Harold_V

Strider said:


> Hello...I was wondering...how much would a bar like that cost in jewlery stores? More than the same amount of gold?



Blink!

Blink! :?: 

Can you be somewhat more specific? Which "bar" is it you speak of? If it's a Milky Way, I've not seen many of them in jewelry stores. 

Harold


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## lazersteve

I think he's talking about the 18.1 gram platinum bar in the opening post.

It's worth about:

18.1 /31.1 * $1207 =~ $702.47 

at today's spot.


Steve


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## Harold_V

Thanks, Steve. I didn't go back far enough for the post to make sense. That's a great example of reasons why folks should try to either quote, or make references when a statement can be vague.

Very nice piece of platinum, Steve. I have the fondest of memories of working with platinum and palladium. I found both of them to be fascinating. 

Harold


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## Strider

lazersteve said:


> I think he's talking about the 18.1 gram platinum bar in the opening post.
> 
> It's worth about:
> 
> 18.1 /31.1 * $1207 =~ $702.47
> 
> at today's spot.
> 
> 
> Steve


DAMN! THIS WILL BE MY FUTURE LIVING :mrgreen:


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## siconic

g_axelsson said:


> You need the aqua regia (AR) to dissolve the platinum. Pure hydrochloric will not affect the platinum.



Actually, 10HCL:1H2O2 (37%HCL and 35%H2O2) will dissolve platinum at room temperature far better than Aqua regia. However, heated, aqua regia will outperform, and optimal temperature is about 70 C. For the HCL:H2O2 Mixture, optimal is 80 C, and very close to the best dissolution rates for aqua regia. This would also eliminate the need for nitric acid, and the need to Denoxx the mixture... Just my two cents.


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## samuel-a

in most cases, 35/ h2o2 cost more then 70/ nitrc acid per liter


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## suhailkhan8547

Hi everyone, I have platinum ash which I have got from catalytic convertor after hard-working. Now anybody can tell me what will be done to convert it into pure platinum. Which type of chemical agent mix to melt it on furnace (Any solution, method, idea to make it a pure platinum coin). Appreciable If you have some videos or file to share.
Please...............  

Thanks


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## jimdoc

suhailkhan8547 said:


> Hi everyone, I have platinum ash which I have got from catalytic convertor after hard-working. Now anybody can tell me what will be done to convert it into pure platinum. Which type of chemical agent mix to melt it on furnace (Any solution, method, idea to make it a pure platinum coin). Appreciable If you have some videos or file to share.
> Please...............
> 
> Thanks



What exactly is "platinum ash"? 
And what exactly did you do to get it?

Jim


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## suhailkhan8547

Hi Jim, I exactly got it from catalytic convertor. First of all, I collected some catalytic convertor and drop them in a chemical approximate 8-10 days. After that I got platinum in very-2 small situation with many impurities. Then I dropped this in AR solution and heat it some minutes. Everything had mixed. After some time, I mixed sodium sulfade in it and It started to convert into platinum ash. It is 240 grams. Now I don't know what to do to continue with this process......I want to make it pure platinum coin. If you have any video or pdf please share to me. I want to do this...........

Thanks to all


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## jimdoc

Lazersteve's platinum DVD is worth buying, as are all of his videos.
There is a lot of information on the forum also, if you search.
You said "drop them in a chemical approximate 8-10 days"
What chemical? How many converters? What type of converters?
You should state all possible info to get a proper answer.
Jim


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## jjohio

awesome show Steve


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## nmcs87

lazersteve said:


> All,
> 
> Since I was off for Veterans Day today, I decided to take advantage of the free time and make a Platinum Slide show for the Forum...
> 
> 
> Platinum Refining
> 
> Let me know what you think.
> 
> Here's a photo of the resulting 18.1 gram Platinum Bar:
> 
> 
> 
> 
> 
> 
> 
> The photo does the bar no justice. It's glaring to look at it is so shiny. I had to turn off the flash due to the glare.
> 
> Needless to say, I had a wonderful day today. 8)
> 
> Steve



I have a question, in the video you got to an orange powder, how did you get from powder to metal?

Another, in this process if you had platinum and rhodium, when dissolving, will both be dissolved? if so, who do you separate?


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## lazersteve

There are several routes from the orange/yellow powder to Pt sponge.

The traditional method is slow incineration of the colored powder to drive off the ammonium chloride. My DVD Fundamentals of Platinum and Palladium demonstrates this method.

Since making the DVD I typically employ either Zn/HCl or NH4OH/Hydrazine, I prefer the Zn route as it is relatively quick and makes an easy to handle product. 

After making the sponge by one of the methods above (or others) simply melt the sponge in a high temperature dish with Hydrogen/Oxygen. Acetylene/Oxygen will work, but there are risk of losses and the final product is not as clean.

Search the forum for information on the methods I mention above.

Steve


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## nmcs87

lazersteve said:


> There are several routes from the orange/yellow powder to Pt sponge.
> 
> The traditional method is slow incineration of the colored powder to drive off the ammonium chloride. My DVD Fundamentals of Platinum and Palladium demonstrates this method.
> 
> Since making the DVD I typically employ either Zn/HCl or NH4OH/Hydrazine, I prefer the Zn route as it is relatively quick and makes an easy to handle product.
> 
> After making the sponge by one of the methods above (or others) simply melt the sponge in a high temperature dish with Hydrogen/Oxygen. Acetylene/Oxygen will work, but there are risk of losses and the final product is not as clean.
> 
> Search the forum for information on the methods I mention above.
> 
> Steve



Do you mean you get the sponge after slow incineration? and then melt in a high temperature dish with Hyrogen/Oxygen or Acetylene/Oxygen.
Did I understand this correctly?

How much for the DVD? how could we do?, I live in Costa Rica.


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## lazersteve

Yes.

Check my web store for DVDs and supplies:

http://goldrecovery.us/pricing.asp

The DVD is $25 plus shipping.

Steve


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## shan1khan

hello friend im new in this topic plz tell me wheres is find platinum powder from copmuter scrap and how can i pic this plz im waiting


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## lazersteve

Computers scrap is not the place to be looking for realistic quantities of Platinum.

I would suggest you find some catalytic converters, dental scrap, or medical scrap if you want to have a reasonable amount of Pt to work with.

Steve


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## Jef

There is a Turkish paper on the web with regards to platinum from catalytic converters that uses hydrogen peroxide instead of nitric.


BigDallas said:


> Oh ok thanks, g_axelsson.
> 
> That is what I thought, but my main problem is that I have been encountering some difficulties finding some nitric acid here in the Czech Republic. I am trying to make some calls to some chemical and laboratory stores here.
> 
> Thanks again. Dallas


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## Jef

There are many suppliers of H2O2, and I think hydrogen peroxide can be acquired in barrel lots.
rebekahs is where I order my hydrogen peroxide from but the problem with 
small batch orders of 35% is that it requires a hazmat cert to ship which last time I looked 
adds $35 to the cost, so it is impractical to buy less than several gallons at a time. It does 
produce less toxic fumes in AR use. 

What I really appreciate in this forum is that I have been trying to get the formulas to recover 
platinum from my concentrate and it looks like this is the place.



samuel-a said:


> in most cases, 35/ h2o2 cost more then 70/ nitrc acid per liter


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## etack

find a farmer 35% H2O2 is common for livestock. I think it is sold at tractor supply I know it is at the feed store.

@ $28.00 a gallon

Eric


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## Jef

etack said:


> find a farmer 35% H2O2 is common for livestock. I think it is sold at tractor supply I know it is at the feed store.
> 
> @ $28.00 a gallon
> 
> Eric



Thanks, the stuff I get is food grade which I use in my detox practice for patients, but food grade is not required for this.


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## Jef

etack said:


> find a farmer 35% H2O2 is common for livestock. I think it is sold at tractor supply I know it is at the feed store.
> 
> @ $28.00 a gallon
> 
> Eric



Thanks Eric, the type of hydrogen peroxide I use is food grade which I use for my patients in detox. Food grade is not required 
for this application, though I do wonder if the % recovery and recovery time might be improved with food grade vs industrial.


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## kirk34100

If you have your Platinum/palladium in solution, why not just hook up a battery and a couple resistant (titanium or platinum group) electrodes and plate the metals out on the cathode?


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## lazersteve

If you have known pure solutions this could be a viable idea, but rarely are Pt solutions from scrap pure, in fact they are usually very dirty.

Steve


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## Mgnaing

Does yellow color of precipitate indicate pure of platinum and orange color precipitate indicate dirty present?


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## Lou

Color and fluffiness of the precipitate do indicate purity.

Very pure will be yellow and of low density. Highly compact chloroplatinate salts are often of lower purity.


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## JamesNReed

Hi All,

I did some testing trying to get the platinum and palladium out of catalytic converter material. Here's how I went about it. I started with a handfull of honey comb from a 
converter. Put a stainless steel piece for the anode and used a carbon welding rod for the cathode. Hooked up the battery charger using 10 amp/ 2 volts. Then I put it in 
a solution of water, urea, and added table salt till an orange liquid started forming near the cathode. Not sure if this is platinum. Then after it ran for a little bit and
the orange powder formed near the cathode I added some food grade hydrogen peroxide to see what would happen. I then got an orange/brown liquid forming near the anode.
Waiting to hear back from a source to see if this is platinum and palladium. Anyone have any insights? Any thoughts are greatly appreciated.

Thanks,

James


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## butcher

I am a bit amused and confused by this:
Just some thoughts.

How are you expecting to put the metals into solution with this process, without having the metals in contact with the anode to oxidize them?

just doing some thinking on the electrolysis of this mix.
salt makes a good electrolyte, urea will not, but urea can be split, as well as the water, I see several gases easily being evolved from this, water forming hydrogen at cathode, and oxygen at anode or a hydroxide at anode area, urea forming nitrogen gas at the anode, and hydrogen at the cathode, CO2 gas at anode and possibly ammonia at anode (maybe pH dependent?), NaCl salt splitting to form chlorine gas at anode and sodium at cathode, now hydrogen peroxide decomposing to water and oxygen acting like water in the cell supplying hydrogen gas at cathode and oxygen at anode.

I am confused by what all reactions you think you will get, I would be more concerned with the gases produced. like the hydrogen and oxygen. Be careful around a source of ignition like sparks from a bad connection to the power supply and do not let these gases build up in a confined area.

I am interested in what you find in the powders, this could have a lot of components being formed at the anode area some may have an affect on the platinum group, like possibly ammonium chlorides, or nitrogen compounds, I really do not know, but overall I would not expect the combination or cell to work as a recovery method for the platinum group from powdered catalyst materials, but I would expect it to form a lot of gases at the electrodes, several of which may be hard to detect they are being evolved as they may not smell.


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## Mgnaing

In my country , refining platinum group metals scraps , first removing base metals with nitric acid and wash well . Then digest the PGM scraps with aqua regia , and denox . Then add anhydrous sodium sulfite to precipitate if gold present and also iridium will precipitate if present . Then add hydrogen peroxide to the main solution containing platinum and palladium. After that precipitate platinum out with ammonium chloride and wash well and reduce with hydrazine hydrate. Then precipitate palladium out with DMG . And then reduce the final solution with zinc . In this process , I don't understand why using hydrogen peroxide and what is the action of H2O2 ?Can anyone explain me the action of H2O2 in this process ?

With thanks , Mg Naing .


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## Mgnaing

Lou said:


> Color and fluffiness of the precipitate do indicate purity.
> 
> Very pure will be yellow and of low density. Highly compact chloroplatinate salts are often of lower purity.


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## GotTheBug

For the ones looking for hydrogen peroxide at a decent cost. Pool supply. A product called softswim C is 35% and last time ran me $15.


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## Lou

Good rinse is 2 M NH4Cl and 0.25 M HCl.


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## Mgnaing

Lou said:


> Good rinse is 2 M NH4Cl and 0.25 M HCl.


 Thanks lou .


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## Dellrugby

That is awesome. I have 44 grams of dental PM so far, I have pulverized the pile to get rid of the dental debris. I am wanting to learn how to refine it now. Hope I will have a Platinum little ingot like that soon! I tested it, there is platinum, Palladium, Silver and Gold in most of the pieces I have collected.


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## Joeyboots

I have come across some material that contains platinum. It comes from some ore that was heated in a furnace with some lead added to catch the platinum. How would I go about leeching the platinum from this slag material? I looked into CDE leeching and have seen some Aqua Regia examples. But I am very new to this and would like to refire the metal myself because it will be the only way to turn a profit I believe.


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## solar_plasma

JamesNReed said:


> Hi All,
> 
> I did some testing trying to get the platinum and palladium out of catalytic converter material. Here's how I went about it. I started with a handfull of honey comb from a
> converter. Put a stainless steel piece for the anode and used a carbon welding rod for the cathode. Hooked up the battery charger using 10 amp/ 2 volts. Then I put it in
> a solution of water, urea, and added table salt till an orange liquid started forming near the cathode. Not sure if this is platinum. Then after it ran for a little bit and
> the orange powder formed near the cathode I added some food grade hydrogen peroxide to see what would happen. I then got an orange/brown liquid forming near the anode.
> Waiting to hear back from a source to see if this is platinum and palladium. Anyone have any insights? Any thoughts are greatly appreciated.
> 
> Thanks,
> 
> James



Though this whole thing sounds like a big mess and not like a method, it has some interesting angles. As we know NaCl/H2O-electrolysis forms (very simplified) NaOH and Cl2 as pgm-active components. If chlorine would dissolve pgms to cations (a problem occurs if they form complex anions), they would be attracted by the cathode, where they will meet NaOH and high pH, which would end in a hydroxide precipitation and/or sodium pgm-metallates. Urea makes this whole thing unpredictable to my low-medium grade chemistry knowledge, but as butcher already said, NH3 may play a role.

Just a possible and not complete explanation, what might have happened. I am pretty sure, this is not very handy, if it works at all.

Where do you have this idea from, can you show us some links?


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## solar_plasma

Something that wonders me right now is, platinum electrodes are normally referred to as being inert in a NaCl-electrolysis and I never saw any corrosion of the electrodes, though chlorine of course at least to a minor degree dissolves platinum. Obviously this effect is negligible when the platinum is not finely devided.


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## butcher

I am not positive about this, and can be wrong here.

My thinking is that the metal which may be inert, in some instances the metal being inert does not mean that the metal cannot be attacked, but that it is so easily oxidized on its outer layer that it builds a protective coating, and it is this coating which make it inert to further attack.

Something like silver where its outer layer is attacked by HCl, this silver outer silver layer is oxidized, the removal of electrons which combine with the reduced acids chlorides to form a passivated layer or coating, the outer surface is converted to silver chloride, building a protective coating insoluble in the acid, this layer of silver salt which protects the unexposed metal under this layer of silver chloride from being attacked any further by the surrounding acid, the oxidized layer of silver does not dissolve in solution, or is not easily broken away from the remaining metal, pretty much makes the silver inert from further acid attack.

Some metals are so easily attacked by a substance that they build a coating that can help to protect them from further attack, iron, lead, and aluminum come to mind here also.

Iron is so easily attacked by water and air, or moisture and the oxygen in the air the rust or oxidized iron can form a protective layer of iron oxides that can help to slow the attack of the iron below.

Lead is easily attacked or oxidized by our environment, that it quickly builds an oxide coating, this protective coating can keep a chunk of led from dissolving further or breaking down, in our environment or being introduced easily into our water supply , our rivers or our underground water supply’s we drink from, you can find lead bullets hundreds of years old with this oxide coating that are almost the same shape as they were the day they shot from the gun.

Aluminum is also so easily attacked it also build a protective coating.

I am not sure if this is the case with Platinum when used as an inert anode in this case, or not, but I suspect it to be the case. That the Pt is initially easily attacked in this enviroment, but quickly builds a protective coating, or a passivated layer or coating that protects the underlying metal from further attack or oxidation.


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## butcher

Joeyboots,
Double posting the same question will not help, if you do not get a response from a post there is most likely reasons, double posting just wastes forum space and members time, and frowned on because of the problems it causes.

Your question you did not give much detail in the question, to go by, to get an answer, several things may help to get some answers, like How do you know this original ore had PGM's, what did the assays show, you say you have a material with a possible platinum content, where it sounds like lead was used as collector in what sounds like smelting was used as recovery method, how much of this lead do you have, or are you trying to deal with?. How do you know it actually contains value? You also asked how do you recover the platinum from the slag, if the smelting operation was originally done properly, you should not have any considerable valuable metals let in the slag, to recover, especially by some type of acid process.

It does not sound like you have spent much effort studying, from your questions, and you have little clue, if this material actually contains value, or knowledge of the smelting operation of ore, or the recovery method used to recover the valuable metals from the lead that was used to collect these metals from the ore in the smelting operation.

Study will be the best help for your problem at this point, study how platinum and other metals are collected in a smelting operation, study how assays are done, how lead is separated from the other metals with cupelling in the assay methods.
Basically you need know what you have for sure, and how to deal with it, to part the lead from the values, which normally need to be done before putting these metals in aqua regia…

So my answer to help you with your problem is, for you to get busy studying, so that you have a better understanding of the basics and basic principles of recovery and refining.
I deleted your other post of this same question.

Welcome to the forum, studying here will help you with your questions, and help you in learning the basics, so you can get better at finding the answers you seek, and having a better understanding of how to ask questions or help from other members when you cannot find the answers through your studying or need a few details to fill the gaps.

Begin with Hoke's book and reading the forum, most of the answers you seek can be found with some work, but first you need to understand the basic principles.

Do not double post questions, if you post it will be read by the mmbers, and if someone thinks they can help you with an answer they will, if they do not get an answer it may be a sighn that you need to spend more time learning.


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## Toddntucson7

Would a cheap way for nitric for AR just to buy a test kit for 14 dollars and combine the 10k, 14k, 18k, and 22k on eBay? I don't know but that's how I have been using AR on small things I'm doing. Reduce the acid to make stronger.


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## Toddntucson7

I don't know I have never had any problems getting chemicals from the local chemicals supply either, maybe it's different from state to state but I was getting acids in California in 1992 no problem. Just picked up some powders for tanerrite impact targets not too long ago in AZ. They said a lot of miners are using that combo instead of dynomite now for small claims charges due to cost and regs. I know I wouldn't want to step in a hole after someone did that. I just was given 4 cats from a diesel I have to pick up and going to try. I heard they were the good ones. He tried crushing the comb on one and torching it and panning it didn't know what he was doing. So one is coming in a big bag of powders. Might just send them off to one of you and split the money so I don't waste the other 3 learning.


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## Topher_osAUrus

Some diesel cats dont have pms. But, some do, according to-http://www.preciousmetals.umicore.com/recyclables/SAC/catalyticconverter/

Also, (I know you didn't do it, but,..) dont crush the innards to powder. 

It makes recovery difficult for many reasons.
-you need constant agitation
-powders sitting on the bottom of glass can create hot spots and fracture the vessel
-Pt, and her sisters, are pretty resilient to acids (Pd can be leeched with HCl before AR/HCl+Bleach)
-some pgms, will never be leeched out...they are too stubborn, and the wash coat is damn near impossible to get to cooperate
-more i can't remember at this second, but are 

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=51&t=20573

That's is an excellent thread by Kurt on cats. Like your other post, probably not what you were looking for exactly..but.. There it is.. Have you had a chance to poke around the library yet? Or read Hoke's book?...she is wonderful...and in her book she teaches how to refine PMs and test for them.. Its a great book written for laymen, that is invaluable to anyone who wants to pursue this field. -theres a reason why everyone here endorses it- (maybe there's a secret somewhere in there that nobody is allowed to post on the forum because its that all illusive magic-bullet to get the PMs with the slightest of.ease!...) no, thats a lie.. But it will put you well on your way to understanding the intricacies of refining.


Best of luck in your new endeavour!

-topher, the talker-upper


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## sugianto

The video would be great if it shows the melting process....
Anyway, it is awesome. :shock:


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## Sinnaduray

Hi all, I precipitated a light green powder from aqua regia using ammonium chloride, nitric acid free after evaporating down. Source material is catalytic converter. I heated the green powder and it turned bright yellow and further heating turned into a grey black powder. It will not dissolve in nitric, sulfuric and hydrochloric acid. Is it platinum? Need help.


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## Lou

It is likely platinum contaminated with rhodium.


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## Mgnaing

By the help of Lou , I have made 9998 of Platinum ,Thanks a lot to Lou ,my teacher.


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## Gigidag

Dear Lou,

We have a question concerning dropping down Platinum from aqua regia solution.

Unfortunately when we drop down with ammoniumchloride we still have around half of the amount of the platinum in the solution. What can we do?

Your help is highly appreciated.

kind regards


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## Aunderwood458

Does any one know the initial metal that was used?


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## g_axelsson

Aunderwood458 said:


> Does any one know the initial metal that was used?



See my other response in the thread you just started.

Göran


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