I am making aqua regia using a 3.5 to one HCL to Nitric. The nitric I am using is Lasersteves method without distillation, roughly 50 %. Upon cooking down to remove excess nitric I am finding a salt substance that is falling out of the AR. I do have positive stannous chloride tests for palladium, dark green from ore I mine. Can I prevent this salt from forming by investing in distillation equipment for nitric acid? I am also going to have to completely cook down until I get no more salt dropout from the AR. I did do a small test using sodium chlorate about 0.10 grams and did get some red powder to drop but it did take about 20 minuets to precipitate.
AR Help
- Thread starter mikes1066
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With home made nitric acid (nitrate salt and sulfuric acid), you get a sulfate salt as a byproduct.
We can chill the solution to remove a good portion of the sulfate salts, by lowering their solubility with temperature of the solution, but we cannot remove all of the sulfate salts by this method, too get a cleaner nitric acid distilling is the way to go.
In some processes a little of the sulfate salts do not make much difference. like when dissolving copper and base metals in a recovery process, or with a homemade aqua regia for getting the gold to dissolve from CPU's.
In other processes we need a cleaner sulfate free nitric acid, like when working with silver, so we do not form silver sulfate in the process, or where we may be working with PGM's where we need to form highly concentrated solutions, or where the concentrated sulfate could give problems...
Looks like your best option would be to study distilling and the safety aspects involved, and learn to distill your nitric acid, or purchase your nitric acid.
With working with ore you can also have many different chemical complexes going on with the acids and the ore, you may have other reactions going on from the chemistry of the ore and the acids...
Red powder could just be iron hydroxide, with ore using aqua regia, and not having a clue to what your working with or how, I would be reluctant to think this red powder is a PGM without further proof.
We can chill the solution to remove a good portion of the sulfate salts, by lowering their solubility with temperature of the solution, but we cannot remove all of the sulfate salts by this method, too get a cleaner nitric acid distilling is the way to go.
In some processes a little of the sulfate salts do not make much difference. like when dissolving copper and base metals in a recovery process, or with a homemade aqua regia for getting the gold to dissolve from CPU's.
In other processes we need a cleaner sulfate free nitric acid, like when working with silver, so we do not form silver sulfate in the process, or where we may be working with PGM's where we need to form highly concentrated solutions, or where the concentrated sulfate could give problems...
Looks like your best option would be to study distilling and the safety aspects involved, and learn to distill your nitric acid, or purchase your nitric acid.
With working with ore you can also have many different chemical complexes going on with the acids and the ore, you may have other reactions going on from the chemistry of the ore and the acids...
Red powder could just be iron hydroxide, with ore using aqua regia, and not having a clue to what your working with or how, I would be reluctant to think this red powder is a PGM without further proof.
Thank you for the advise on distilled nitric acid. I will begin looking into purchasing some equipment. I have melted some of the red powder in a quick kiln and got a white metal that is very hard to melt and non magnetic. I also had to change the gas from propane to map gas . The melt took about 25 minuets.
I have also added aqueous oxalic acid to my AR and heated to near boiling. The percipitant is a light blue whitish sticky substance that when rinsed and filtered turns yellow in the sun shine after about 3 days. I get the same substance upon using solid copper in my AR, cement process. Upon using ammonium chloride I do get solid magnetic metal ( iron sulfate ? ) and some redish orange powder.
I first boil my ore in water and test with litmus paper. Tests show a ph of 2 or better. I continue replacing the water with fresh until I cannot detect any more acid. Then boiling one more time. I usually start with about 150 grams of ore and about 600 ml of water. I have to boil the ore 4 or 5 times.
The reason I think I have some PGM metals is that I have to heat my AR to about 75 degrees C for anything to dissolve. I use a water bath at near boiling and use a thermometer to check the temp of the AR. Leaving my ore in AR at room temp covered for 2 or 3 days yields very little color change and ph tests 2 or better. After heating for about 7 hours the ph drops to between a 4 and 5. So upon heating I have a good chance of dissolving something desirable.
Another reason I think I am on to something. I did borax heat process about 2 grams of ore with a map torch. I did find 4 small pickers I took to a gold show. One of the gold dealers there had a hand held xrf scanner. he tested the pickers and found 94% gold, 3% copper, and 3% iron. The total weight was 0.15 grams. Between 5 and 10 bucks in gold. So I know I am on to something, exactly what I do not know yet. This is the main reason I will continue trying and not give up. Finding and then fixing errors and contaminates is my main purpose for now. Getting good yield and pure metals will come after fixing errors and problems.
Could you recommend some distillation equipment. I was considering 2 erlimer flasks and a condensing tube with pre holed stopper and bracing stand. I have a portable screws on top of a propane bottle camp stove about 10,000 btu for a heat source. I am working outside.
Again, Thank You for your help and advise. Any further help is most welcome.
I have also added aqueous oxalic acid to my AR and heated to near boiling. The percipitant is a light blue whitish sticky substance that when rinsed and filtered turns yellow in the sun shine after about 3 days. I get the same substance upon using solid copper in my AR, cement process. Upon using ammonium chloride I do get solid magnetic metal ( iron sulfate ? ) and some redish orange powder.
I first boil my ore in water and test with litmus paper. Tests show a ph of 2 or better. I continue replacing the water with fresh until I cannot detect any more acid. Then boiling one more time. I usually start with about 150 grams of ore and about 600 ml of water. I have to boil the ore 4 or 5 times.
The reason I think I have some PGM metals is that I have to heat my AR to about 75 degrees C for anything to dissolve. I use a water bath at near boiling and use a thermometer to check the temp of the AR. Leaving my ore in AR at room temp covered for 2 or 3 days yields very little color change and ph tests 2 or better. After heating for about 7 hours the ph drops to between a 4 and 5. So upon heating I have a good chance of dissolving something desirable.
Another reason I think I am on to something. I did borax heat process about 2 grams of ore with a map torch. I did find 4 small pickers I took to a gold show. One of the gold dealers there had a hand held xrf scanner. he tested the pickers and found 94% gold, 3% copper, and 3% iron. The total weight was 0.15 grams. Between 5 and 10 bucks in gold. So I know I am on to something, exactly what I do not know yet. This is the main reason I will continue trying and not give up. Finding and then fixing errors and contaminates is my main purpose for now. Getting good yield and pure metals will come after fixing errors and problems.
Could you recommend some distillation equipment. I was considering 2 erlimer flasks and a condensing tube with pre holed stopper and bracing stand. I have a portable screws on top of a propane bottle camp stove about 10,000 btu for a heat source. I am working outside.
Again, Thank You for your help and advise. Any further help is most welcome.
There are several variations of lab glass distilling rigs that can be used, here is a basic setup, you can usually find them from les than $100 and up depending on your needs.
Be sure to study how to do the distilling and the safety aspects, example in the heated flask if the heat is shut off, or the heat lowered, (without first breaking the seal) with some types of rigs will form a vacuum, sucking back cold liquids into the hot glassware full of hot acid, bursting the hot glass and hot acids all over you or your lab.
You cannot use rubber corks or seals, nitric makes it a gooey mess, all glass joints or Teflon, or some material compatible with the nitric and the heat generated.
I have made my own distilling rigs out of some common glassware (Erlenmeyer flask style Pyrex coffee pot from second hand store with Teflon cork and tubing) or even a (gallon pickle canning jar in a sand bath with Teflon lid and tubing) doing a search for killing two birds with one stone with butcher as author can give some details on the homemade lab ware I used and the distilling process.
Be sure to study how to do the distilling and the safety aspects, example in the heated flask if the heat is shut off, or the heat lowered, (without first breaking the seal) with some types of rigs will form a vacuum, sucking back cold liquids into the hot glassware full of hot acid, bursting the hot glass and hot acids all over you or your lab.
You cannot use rubber corks or seals, nitric makes it a gooey mess, all glass joints or Teflon, or some material compatible with the nitric and the heat generated.
I have made my own distilling rigs out of some common glassware (Erlenmeyer flask style Pyrex coffee pot from second hand store with Teflon cork and tubing) or even a (gallon pickle canning jar in a sand bath with Teflon lid and tubing) doing a search for killing two birds with one stone with butcher as author can give some details on the homemade lab ware I used and the distilling process.
Attachments
Thank you for the help. I will do more reading on distillation and find something usable on ebay.
I did do some cooking down and added 300 ml HCl and detected no red ( nitric fumes ) gas. The run is now about 700 ml from 4 batches 100 ml nitric and between 300 and 400 ml HCl and 200 ml water. I did get a small amount of salt out. I will cook down some more after filtering and will use another 300 ml HCl for degas.
I will look for a good recipe for distilling nitric, checking the forum first, and safety .
Thank you again.
I did do some cooking down and added 300 ml HCl and detected no red ( nitric fumes ) gas. The run is now about 700 ml from 4 batches 100 ml nitric and between 300 and 400 ml HCl and 200 ml water. I did get a small amount of salt out. I will cook down some more after filtering and will use another 300 ml HCl for degas.
I will look for a good recipe for distilling nitric, checking the forum first, and safety .
Thank you again.
The first try at nitric acid was a nice success. I made my AR for 1 part nitric 50ml to 4 parts HCl 200ml and 2 parts water 100ml. Made 350 ml of aqua regia. My ore did nothing in 4 hours at room temperature. Upon heating in a water bath for 10 hours everything turned a nice blood red color. When cooled to room temp the color changed to a orange red color. I did weigh my 350 ml of AR and have a weight of 404 grams. I started the with 153 grams or ore. A considerable amount of ore has dissolved. Stanous chloride test is so dark a color of green, purple , or black the best I can get. When the weather warms up a bit I will cook down and degas. I will being doing my percipitation tests in test tubes individually. What is remaining of the ore looks a nice white silvery gray color. I know the ore is more than likely highly mixed but at least its no longer magnetic.
Thank you again for any suggestions in advance.
Thank you again for any suggestions in advance.
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It's not clear to me what your objective is, but it is well understood that extracting values from ores using acid isn't generally successful. Even if it is, consumption of acid can easily overcome the value gained, to say nothing of the huge volume of wastes generated. You may wish to rethink what you're trying to do.
Harold
Harold
necromancer
Well-known member
mikes1066 said:
did you take photos of this ore before adding it to the AR ?
we all like photos
kurtak
Well-known member
Harold_V said:
What Harold said :!:
Kurt
I guess that I should state that I melted 2 grams of this ore using borax and a MAP gas torch. True I used most of a bottle of MAP gas but did achieve 5 small nuggets of gold with a total weight of 0.15 grams. Hay I struck gold. XRF scanner results at a gold show indicated 94% gold, 2% copper, 4% iron. Not bad. The reason for attempting the aqua regia is simple. What else am I going to find. To attempt and fail is one thing but to have never tried is another. At least I am using my 2 engineering degrees for something that might benefit me. I have had stanus chloride detection success for platinum and palladium. I also was fortunate to send samples out to a processor and the test results are mixed platinum, palladium, rhodium, gold ,small amounts of silver , and trace amounts of mercury. I have yet to find a heat only process that deals with all of these metals, but I will keep looking anyway.
Thank you in advance for any and all assistance.
Thank you in advance for any and all assistance.
mikes1066 said:
You found mercury after melting.... That sounds really ominous, I hope you have decent extraction and scrubbers that will extract any metals or oxides before realising into the atmosphere or you have a potential hazard on your hands, not sure where you are from but if it's a country with regulations your going to get fried!
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????mikes1066 said:
That has to be one hell of an ore.
I've personally processed high grade gold ore. One that ran over 300 ounces/ton (about 1% gold content), in fact, but yours makes it look like common dirt.
Assuming your numbers are correct, you have an ore that contains about 7½% gold. Very good, even for a concentrate.
Am I missing something?
Aside from the mercury, I see no issue in collecting the values by furnace. Mercury is a deal killer, however.
Assuming you really have an ore that assays 7½% gold, yeah, you could process with AR, although you'd not recover any of the silver, and probably none of the rhodium, but I'm having more than a little trouble believing you really have an ore that good. A sample? Yeah, very possible. A source for more? Highly unlikely.
Harold
jason_recliner
Well-known member
WAWA! :mrgreen:Harold_V said:
Those are really high numbers. When something appears too good to be true, it probably is. If this is something you dug up yourself, then great - I wish I were in your position. But if you're being offered 2 gram samples, please seriously consider the possibility you're being scammed.
kurtak
Well-known member
mikes1066
you keep making a reference to ore - are you talking about "the" ore in & of its self - or are you talking about the concentrates from the ore
in other words ore that you have crushed & then concentrated by panning or other concentrating method (table, blue bowl etc.)
I ask because your numbers sound "unbelievably" high to be the ore its self & sound more realistic to that of concentrates from ore
Kurt
you keep making a reference to ore - are you talking about "the" ore in & of its self - or are you talking about the concentrates from the ore
in other words ore that you have crushed & then concentrated by panning or other concentrating method (table, blue bowl etc.)
I ask because your numbers sound "unbelievably" high to be the ore its self & sound more realistic to that of concentrates from ore
Kurt
necromancer
Well-known member
that's why i asked for photos, 350 ml of AR with 153 grams of ore turning "red" is a little off the chart.
I will look for my camera and send pictures. On the ore issue, these are concentrates I dug myself and ran through a sluce box and then panned down. I did send a sample of roughly 2 pounds of crushed rock to a processor and they came back with 6 grams of metal. Of that metal 50% rhodium 50% palladium unfortunately the processor only deals with recycled material and is not allowed to deal with mined material. I know, every time I give some form of results I get the nay sayers and environmental people. Please I am trying to find the answer to a problem and try to make some money.
necromancer
Well-known member
mikes1066 said:
nay sayers ?? 2 pounds of rock = 6 grams of metal, 50% rhodium 50% palladium, did you get a assay or just the 6 grams ?
i am a bit confused by your posts.
mikes1066 said:
you brought your mined material to someone that is not allowed to deal with mined material, they smelted your 2 pounds of mined material & got 6 grams of PGM's ??
i am more then a bit confused.......
necromancer
Well-known member
mikes1066 said:
looks like maple syrup :lol: very nice !
