# Questions about lazersteve's cold nitric acid recipe



## KU4TP

Hello all, 

First, the usual thanks to all that have worked to answer questions here. As a noob to this, you all have been most helpful. 

I have been trying to make nitric acid using lazersteve's cold recipe and the one hurtle I am having trouble overcoming is the dissolving of the 170g of sodium nitrate into the 100ml of water. I've found other posts that mention this so I know I'm not alone but no discussion of what might be wrong. If the post is there and I simply have not searched long enough, I apologize.

Per the instructions I am using 100ml (on some attempts a few ml more) to dissolve 170g - (2M) of sodium nitrate (or slightly less). I have checked temperature each time to verify 100 degrees C except the last time. In that case I used a microwave to heat the distiled water and had violent boiling before pouring off 100ml to use. I am stirring for up to an hour with only short pauses to switch hands or shift my position - no pause was over a minute. in each case (5 now) I have had about the same amount of sodium nitrate left undissolved in the bottom of the container. I am using Nitrate of soda - 16-0-0.
As an experiment on one batch I continued the procedure despite the left over material. Other than the sediment I started out with everything went as described. The resulting sediment I am assuming to be undissolved sodium nitrate with a covering of sodium sulphate. I tested the pour-off in a test tube with a scrap of copper pipe and got the expected green tint and could see a few bubbles from the reaction at first. I also noted a slight dark vapor rising from the tube - also what I would expect. Leaving it standing for a few days I saw only a bit of copper left but had a while sediment in the bottom of the tube. At the end of 5 days the sediment was thicker and the copper was either gone or buried in the sediment and the color was more of a light blue than green.
From what I have observed I am guessing: 1 - I got some form of nitric acid from my test. 2. It is either weaker than the 50% lazersteve describes or is contaminated with other stuff or both.

So the questions are 1. - is there something I am missing when it comes to dissolving the sodium nitrate? 2. - if one were to double the water could one reasonably expect to get something near a 25% solution out of it. From what I have read here that would be sufficient for the first acid steps described on this forum and in Hoke even if one had to wait a bit longer for the reaction to eliminate the base metals you need eliminated. (is that last statement correct?) 3. Any thoughts as to the composition of the sediment in the test tube? 

Other questions / thoughts - The only reason I am concerned about getting nitric is the reclaiming of pins and crushed CPUs (at least for now). I saw a post where lazersteve used his AP for the pins at least but the time was a bit prohibitive. Time for me is not a big issue, so should I give up on the nitric in any case? Time is not such a big deal for me at this point, but the conversation seemed to stop shortly after so I never did get a good feeling for how effective it might be. (as an aside - lazersteve -- you rock! Can't thank you enough for the help and materials you make available.) And IF I could find a source of nitric that did not cost an arm, leg, and other body parts I am fond of I would certainly not bother making it.

Thanks again to everyone that makes this forum and their knowledge available.

Virgil


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## gold4mike

Virgil,

Welcome to the forum! It's good to see that you have searched for an answer before posting your question. My experience making nitric by Lazer Steve's method is limited - I've done it twice. I bought a combination hotplate/stirrer off eBay that was non working, repaired it (broken wire) and used it to dissolve the nitre. I had no problem getting it to dissolve either time. I removed the stir bar before adding the acid so it wouldn't get buried in the white cake. 

My best guess is that you simply need more stirring. I know you said that you only took a short break from stirring, but a stirrer will really get the job done with much less effort on your part. 

It does sound as though you have successfully made nitric acid, and I agree with your assumption that it may be a bit weaker than intended, but still capable of doing what you need it to do.

You didn't mention the length of time you cooled the mixture before pouring off the nitric, or how cold you got it. I use an ice & rock salt mixture to bring it below 0* Celsius (in a cooler) and let it chill for 5 hours or so to make sure all the precipitant has come down before pouring off the nitric. 

With that method I haven't had any problem with it continuing to drop the white material while in use.


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## KU4TP

Thanks for the reply. 

In answer to your question - I used the ice and rock salt as well for about 2-1/5 hours. Temp never got above -5 C the whole time. I think I'll try putting the mix in a jar with a lid and spend time agitating it that way. And leaving it in the cold bath longer. I'm still curious as to the effect of adding more water. 

I have only done one small batch of fingers using AP - 63g to start with which yielded - at least enough gold to see *S*. The point was to learn how everything reacts and in that aspect I consider it a complete success. Not that I did not make mistakes, mind you but the answers were all here! So now I'm in a harvesting mode and want to do some pins next. Hopefully enough to get a small button out.


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## glorycloud

Yeah, it takes about 500 grams (1 pound) of fingers to get a 2gram or so gold button.
I say "or so" because some of the older fingers yield more because they were plated
more thickly than the newer fingers. Some of the old mil spec fingers are nice!!!!


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## lazersteve

KU4TP said:


> I'm still curious as to the effect of adding more water.



A little extra water won't hurt. 

Here's a few more tip's on a new improved cold nitric acid method:

1. You can substitute dry powdered swimming pool pH decreaser for the sulfuric acid. It's sold in all types of stores (Walmart, Lowes, Home Depot, etc) and on eBay for around $2 per pound. It's about 95-98% NaHSO4 depending on the brand. Bonide sells a slightly brown Nitrate of Soda that works great in this recipe. 

 Use 1.4 parts NaHSO4 to 1 part sodium nitrate (ie: 140 grams of NaHSO4 + 100 grams of NaNO3). 

 Dissolve the ph decreaser in 167 mL of 95-100C distilled water for every 120 grams of NaHSO4. 

 When all of the ph down has dissolved, add in the dry sodium nitrate while heating until it also *all dissolves*. Boiling is not required. 

 Filter the hot liquid to remove any debris from the solution.

 Cool to -5C for 2-5 hours. You will see some long, clear, ice like crystals form quickly once the solution reaches the correct temperature. Continue cooling for at least 1 hour after you see these crystals form. If a gel or slush like substance forms follow the directions given here:

Cold Nitric Fix


 Pour off the liquid from the crystals. Expect a volume of liquid slightly greater than the amount of water used. The density of the liquid should be around 1.3 - 1.4 and be 25-30% nitric acid.

The cold method acid is further purified by stirring in 0.1 grams of clean powdered refined silver for every 100 mL of liquid produced. The silver will dissolve and form silver sulfate with any sulfate and chlorides* remaining in the solution. Silver nitrate can also be used. After the silver sulfate/chloride* forms let it settle then pour off the acid again. 

I've been working on more improvements to the method and will post more as I confirm them experimentally.

* Edits

Steve


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## stihl88

Am i missing something, wheres the Sulfuric Acid? This is great news for me because Sulfuric Acid is hard to get here in Australia.

Steve, can i substitute Sodium Nitrate for Potassium Nitrate instead?

And can i pickle my silver in the Sodium Bisulfate also?


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## lazersteve

stihl88 said:


> Am i missing something, wheres the Sulfuric Acid? This is great news for me because Sulfuric Acid is hard to get here in Australia.
> 
> Steve, can i substitute Sodium Nitrate for Potassium Nitrate instead?
> 
> And can i pickle my silver in the Sodium Bisulfate also?



The sodium bisulfate is used in place of sulfuric acid. 

Bisulfate in water can be used as a substitute for dilute sulfuric acid in many instances and should work for pickling gold.

The bisulfate provides the acidic hydrogen needed to convert the sodium nitrate into nitric acid.

I have not tried this reaction with potassium nitrate. Give it a try and let us know what you find.

I'm working on more substitutions in the reaction. All we really need is a source of acidic hydrogen and a source of nitrate. The other key factor is the solubility of the reactants and products.

Enjoy!

Steve


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## Anonymous

Steve you are the Bom+, I never thaught of adding silver to remove the excess sulfate, and if silver nitrate you will not reduce the amount of nitrate in solution, thats great.

I have some calcium nitrate, I think it is problamatic as it does not settle well, but if only a small quantity is used it would clean it also.

Jim


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## lazersteve

Jim,

You'll also notice this method produces zero fumes during the mixing stages. 

Once your water is hot the solids dissolve in a matter of minutes.

Steve


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## Platdigger

Jim, the reason Steve mentions using a bit of silver or silver nitrate to clean up your nitric is
to remove any chlorides you may have from your nitrate source, by forming silver cloride.

Are you saying calcium will form a calcium chloride, that would be easy to separate?


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## Anonymous

I think he covers two bases with the silver, chlorides, and sulfates. My concern is sulfates, they get in the way, chlorides mostly dont.
Now you have to understand, I have very little interest in refining to bullion grade, I can not get paid for it and it takes more time and chemicals. I just want high purity so when I sell I know the amount of metal I am selling. 

So for me, I think just putting a little calcium nitrate will cause calcium sulfate to precip, this will keep the sulfate from causing problems with silver, and lead. 

thats my thaughts anyways, and no need to put silver in to try and get it back later.

As, I said earlier, Steve is tops and I appreciate the fact he shares this information with us, I preformed the cold process a few times but the excess sulfate got im my way, so I got a distillation set. I do not like distilling, always waiting for something to go wrong if you know what I mean. I am going to give his new and to me improved process a go. 

Jim


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## stihl88

lazersteve said:


> stihl88 said:
> 
> 
> 
> Am i missing something, wheres the Sulfuric Acid? This is great news for me because Sulfuric Acid is hard to get here in Australia.
> 
> Steve, can i substitute Sodium Nitrate for Potassium Nitrate instead?
> 
> And can i pickle my silver in the Sodium Bisulfate also?
> 
> 
> 
> 
> The sodium bisulfate is used in place of sulfuric acid.
> 
> Bisulfate in water can be used as a substitute for dilute sulfuric acid in many instances and should work for pickling gold.
> 
> The bisulfate provides the acidic hydrogen needed to convert the sodium nitrate into nitric acid.
> 
> I have not tried this reaction with potassium nitrate. Give it a try and let us know what you find.
> 
> I'm working on more substitutions in the reaction. All we really need is a source of acidic hydrogen and a source of nitrate. The other key factor is the solubility of the reactants and products.
> 
> Enjoy!
> 
> Steve
Click to expand...



Thanks Steve :mrgreen: 

I'm going to give it a go when i run out of sulfuric acid.

Do you think the Sodium Bisulfate and Water solution could be boiled down to produce concentrate Sulfuric Acid, or up in the 80-90% concentrate? To be used in an electro cell!

Regards

Will


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## lazersteve

Will,

I don't think boiling it down will make sulfuric acid as the sodium sulfate will still be in there and the parent compound will form again upon evaporation. 

I believe you can, however; regenerate some sulfuric acid from the mix using other techniques. First you may find that you can form some sulfuric acid by freezing the solution and pouring off the sulfuric acid from the crystallized sodium sulfate very much like the cold nitric method without the nitrate. You may also be able to get sulfuric acid out using ethanol* according to wiki.

Sodium bisulfate can be used to form just about any *volatile acid* when distilled with the appropriate sodium salt (sodium nitrate = nitric acid, sodium chloride = hydrochloric acid, sodium acetate = acetic acid, sodium formate = formic acid, etc) in the proper ratio. You'll end up with the acid in the collection flask and sodium sulfate in the reaction flask. Of course, some of these combinations can also be made using the cold technique also, while others can not due to the freezing point of the resulting acid.

As you can see from the above information, sodium bisulfate is a very useful ingredient for many reasons. It can also be used in Rhodium fusion reaction. At $2 a pound I recommend everyone on the forum has some in their chemical cabinet.

Steve

* Merck Index of Chemicals and Drugs, 9th ed. monograph 8330


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## butcher

Ku4TP, Virgil,
sometime's prill's (fertilizer) balls, are coated, My guess is so they cannot be used easily to make dangerous mixtures, or to dissolve slowly in the garden, or both.

Try crushing the prills (rince may help also) before disolving in hot water.

Steves recipee's are calculated out and give good results, and if you were using pure sodium nitrate not fertilizer prills disolving in water should be a none issue, mainly the hot water is to get the most nitrate to disolve with the least water, so the end product is stronger.

weak nitric can be heated and concentrated up to 68%(azeotropic), driving off water which will evaporate before the NOx does, as long as temperature is not to high, pure water boils 100 deg C = 212 deg F, and 68% nitric boils @ 120.5deg C = 249 deg F, so if temperature kept below this you will loose very little nitric untill you reach 68 percent concentration, then you will stat to boil or vaporate your 68% nitric into the air.
the boiling points change with concentration of the water to acid,for solutions, 

sulfuric acid can help to dehydrate (dry) the nitric.
H2O2 peroxide can also be used to keep NOx from excaping a nitric solution.


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## stihl88

Fantastic, this makes sense Steve...

Thanks once again.

Great thread


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## teabone

Sodium bisulfate is very useful as Steve pointed out and a must to keep on hand for the backyard chemist. I use it a lot as a pickle leach for silver. It cleans it up rather nicely.


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## KU4TP

Thanks again to all for the assist. Sorry for the late reply but my day job calls. Butcher, the last attempt was with the Sodium Nitrate powdered by crushing in a mortar. Almost a fine powder before adding the water. Still no joy. I think I'll try to find another source for the sodium nitrate. Also, lazersteve, I think I'll try your alternate method. I like the idea of reducing my exposure to noxious fumes *S*. If I find out what is causing the problem I'll post to this thread and let everyone know.


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## 2002valkyrie

I did all of this except I never seen the crystals form did I miss them? The mixture is a cold gel. To clairify exactly what I did: 170 ml of H2O heated and disolved 121.1 grams of Sodium bisulfate stir till completely disolved, then add 86 grams of Sodium Nitrate. Put in freezer. 3 hours later gelled. Anybody?


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## Platdigger

I see you put an "mta" in front of your bisulfate.
Are you sure you did not use metabisulfite?

If so, this would be the problem.


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## 2002valkyrie

Platdigger said:


> I see you put an "mta" in front of your bisulfate.
> Are you sure you did not use metabisulfite?
> 
> If so, this would be the problem.




Nope I got both chemicals from Lazersteve himself. I don't know what I did but it can't be right.


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## Anonymous

you make have had them freeze to fast, did you let cool to room them first?
I have a tall skinny glass that I wrapped in insulating foam to have the solution cool from the bottom up.

Jim


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## 2002valkyrie

james122964 said:


> you make have had them freeze to fast, did you let cool to room them first?
> I have a tall skinny glass that I wrapped in insulating foam to have the solution cool from the bottom up.
> 
> Jim



I missed the slow cool section. Can I reheat the solution and try again?


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## Anonymous

I would leave it thaw all the way out then you will have to gently heat to get everything back to the starting point.

Also, maybe you could add a little water and use it like poor mans nitric, it just wont be too good for stuff with silver/lead/cadmium in it.

Jim


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## lazersteve

Valk,

The solution takes about 3 hours in an upright freezer for the crystals to form. Mine stayed liquid until this point using the exact same chemical sources I sent you. I'm not sure why yours formed a gel. 

Are you sure your getting to -5 C ?

Did you use distilled water? 

I guess I'm going to have to break down and do a video of this process once and for all. I've been putting it off for some time now, I might as well get to it.

Steve


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## Palladium

lazersteve said:


> I guess I'm going to have to break down and do a video of this process once and for all. I've been putting it off for some time now, I might as well get to it.
> 
> Steve




Alright !!!! 
A new vid.


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## lazersteve

I'm doing the reaction tonight to be 100% certain of the ingredients I sent him. 

My previous cold nitric batches have used the Bonide brand Nitrate of Soda and I sent him some Sodium Nitrate I bought from dudadiesel (sp?) on Ebay. Maybe the nitrate is not sodium nitrate. I'm sure it's a nitrate as I have used 15+ pounds of it for Poor Man's AR without any problems. I'm using Bisulfate from the same container I poured his out of.

I added the water and bisulfate to an empty 1 L beaker and put the heat on Simmer.
With lots of stirring and swirling I was easily able to dissolve the bisulfate in less than 30 minutes without boiling the water.

Next I added all of the nitrate and stirred and swirled until it was all dissolved. The water was steaming, but still not boiling. This step took another 7-10 minutes.

Next I filtered the hot solution. 

Here's a photo of the hot (90C+) filtered solution of 167 mL distilled H2O + 120 grams of NaHSO4 + 85 grams of NaNO3 from dudadiesel. Total volume with 2- 5mL rinses of the beaker and filter is right about 250 mL.







The solution is 100% clear and free of sediment/crystals.

I'll put it in the freezer once it reaches around 50C.

More photos later.

Steve


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## Oz

Steve,

I have made a good bit of biodiesel and you may find that their source has changed as the chloride impurity is not so critical to their process.


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## 2002valkyrie

lazersteve said:


> Valk,
> 
> The solution takes about 3 hours in an upright freezer for the crystals to form. Mine stayed liquid until this point using the exact same chemical sources I sent you. I'm not sure why yours formed a gel.
> 
> Are you sure your getting to -5 C ?
> 
> Did you use distilled water?
> 
> I guess I'm going to have to break down and do a video of this process once and for all. I've been putting it off for some time now, I might as well get to it.
> 
> Steve



Thank you Steve, But Murphy's Law seems to be written just for me. I will wait for your instructions and results that I should expect to achieve before I try again.


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## lazersteve

I fell asleep last night a left the mix in the freezer over night. The last check I made was @12:30 last night (4 hours in the cold) and no crystals had formed yet.

This morning the mix was a slush like consistency, very different from my other batches using the Bondie brand nitrate. Now that I see the slush, I suspect it is hydrated sodium sulfate as the compound will absorb 10 moles of water per mole of sulfate. This leads me to believe there is a difference in the nitrates that I used. 

What gets me is the dudadiesel stuff is labeled 99% Technical grade sodium nitrate. Maybe it has been relabeled? It works great for distilling nitric and for poor man's AR, but it appears to be different when it comes to the cold nitric recipe.

I'm going to run a new batch using the Bondie nitrate again just to be 100% sure. Previously when I've done the experiment the sodium sulfate formed very nice long clear crystals in the flask once it reached the -5 C.

As for the slush, I let it thaw to around 10C and filtered off the clear layer. This layer will go back in the freezer and we will see what happens next. The slush can also be distilled in a glass rig to get the nitric out, so nothing is really lost. If you are going to distill in the end, there is no sense in freezing first as this just adds an extra step.

I'll post more when I have some real conclusions.

Steve


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## lazersteve

Update:

I started a control cold nitric acid experiment using the Bonide Nitrate of Soda, and immediately noticed a big difference. The hot solution is not thick like syrup as the dudadiesel solution was and secondly the nitrate actually fizzes when added to the hot water and dissolved bisulfate.

I also detected a slight odor of NOx after adding the niter. It foamed about 2" thick in a one liter beaker when added. After the niter dissolved the foam all but disappeared.

These observations tell me already that the dudadiesel nitrate either has an additive or is a less soluble form of nitrate. I suspect it may be potassium nitrate instead of sodium as the sodium sulfate has very a unique solubility curve which makes this cold reaction possible. Maybe he mixed up the potassium nitrate with the sodium nitrate for my order? I'll send him an inquiry once I have the results of the freezing stage.

More to come later today.

Steve


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## butcher

I have noticed some difference in the nitrates I wonder if they are not changing them with other chemicals, or something?


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## lazersteve

The Bonide nitrate batch has been freezing since this afternoon. I checked it a few minutes ago and noticed it too is turning slushy. This leads me to believe that the previous batches I did, where I monitored the crystal growth periodically, turned out the way they did because I poured off the liquid once I saw crystal growth.

I think both nitrates are basically the same now that I have seen similar results out of both. 

The solution to the problem of slushy or gel like formation is pretty straight forward. Simply thaw the solution to around 10C and pour off the liquid portion from the powdered salt that remains. You can vacuum filter the salt out with a glass frit if you have one.

Once you have thawed and poured off the clear liquid, refreeze the liquid. The second freezing should be monitored closely. When long clear crystals have formed, pour off the resulting dilute nitric acid. I have noticed that with this second freezing step the crystal grow relatively fast once the solution cools down. The crystals formed will be long and glass like. 

Here's a shot of some of the crystals after the second freezing:






I'm going to distill the resulting acid and post the actual yield of acid and left over salt in the distilling flask in the liquid from the second freeze.

Here's a shot of the second crop of crystals after the second freeze:






Steve


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## Anonymous

I know that I had braught this up before, but if you cool/freeze to quickly the liquid gets overtaken by the crystal front.
I am pretty good at this because I work on water purification units that actuall freeze water then discard the waste water.
One of the main things that goes wrong is the unit freezes to fast encapsulating the waste water.

Jim


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## lazersteve

Here's a shot of the poured off nitric after adding a small silver nitrate crystal (~0.5 gram) and stirring then settling.






and the solids after pouring off the cloudy acid into a filter.






The large chunk on the right is what's left of the original silver nitrate crystal. About 1/3 of it dissolved.

Steve


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## Anonymous

Steve,
Working out a small batch of this bisulfate process today. Seems to be going according to plan. I cut the quantities based to work with 20 ml of water. I let it cool to room temp and a lot of the salts settled out. I know have a clear but cloudy solution that I am going to put in the freezer now. 

Seems to be a good process to bad pool season is over and the bisulfate is kinda rare around here. 

I do not have silver nitrate to clear out the left over sulfate, but I am going to try some calcium nitrate.

Jim


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## depperl001

stihl88 said:


> Am i missing something, wheres the Sulfuric Acid? This is great news for me because Sulfuric Acid is hard to get here in Australia.
> 
> Steve, can i substitute Sodium Nitrate for Potassium Nitrate instead?
> 
> And can i pickle my silver in the Sodium Bisulfate also?


 
Hi stihl88,

Here in Rockhampton, QLD, you can buy it in 4L bottles of Battery acid for $ 22.00.
May pay to check sellers of lead acid batteries, car batteries.

Regards,

depperl001


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## aurville

Hi,
Here in NSW MO-FLO liquid drain cleaner is available from hardware stores for around $44/L. It is concentrated sulfuric acid.

cheers
aurville


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## Anonymous

HI,
My first experiment gives me false result. As I'm using Nitric acid, HCL, Urea and Sodium bisulphite for gold refining process with waste electronic parts. Firstly, I added Nitric acid (30ml for every once of scrap) and HCL (120ml for every once of scrap) and kept it overnight and filtered the chemical with buchner filter. After that I added urea (1 pound) in one quart of boiling water and mix it in the chemical and after that I added sodium bisulphite (one ounce for every ounce of scrap) with one quart of boiling water and mix it in the chemical. Finally, the mud was started stored it in the bottom. I refiltered with distilled water 5 to 10 times and allow it to air dry. And when I melted the mud it gives me copper instead of gold. I don't know where the mistake I've done. Please clarify my problem in brief.


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## lazersteve

pjchary10 said:


> HI,
> My first experiment gives me false result. As I'm using Nitric acid, HCL, Urea and Sodium bisulphite for gold refining process with waste electronic parts. Firstly, I added Nitric acid (30ml for every once of scrap) and HCL (120ml for every once of scrap) and kept it overnight and filtered the chemical with buchner filter. After that I added urea (1 pound) in one quart of boiling water and mix it in the chemical and after that I added sodium bisulphite (one ounce for every ounce of scrap) with one quart of boiling water and mix it in the chemical. Finally, the mud was started stored it in the bottom. I refiltered with distilled water 5 to 10 times and allow it to air dry. And when I melted the mud it gives me copper instead of gold. I don't know where the mistake I've done. Please clarify my problem in brief.



You did not remove the base metals before using AR. The SMB just pushed the dissolved copper out of the solution as Copper I Chloride. Your gold (if any was there) is likely in the undissolved solids.

Did you test the AR with stannous chloride before adding Urea or SMB?

Steve


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## golddigger2

Hi steve 
You probably mentioned this already but can you use potassium nitrate in this recipe?


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## lazersteve

Yes, potassium nitrate will work. Be sure to use the correct amount of nitrate as required by the molar weight of the compound.

Steve


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## golddigger2

I have tried this recipe using PH down and sulphuric acid. When i used the PH down I got the same results as you with the slushy precipitate. When i used the sulphuric I got the nice long crystals as shown in your pictures. I have placed some copper in the finished nitric but it doesn't seem to be very reactive. I used the sulphuric by weight ie 140grams of sulphuric to 100mls potassium nitrate and then heated untill combined as per the recipe. I then put in the freezer and chilled to -5 degrees C. I believe I have followed the recipe and think the only place I could have gone wrong is with the amount of sulphuric.


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## lazersteve

When using bisulfate, it is used in place of the sulfuric acid. The bisulfate is best used to distill with the nitrate. One mole of bisulfate to one mole of nitrate will give one mole of nitric acid, where as sulfuric acid will give two.

If you like I can show the math on the bisulfate process. 

Steve


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## philddreamer

_When using bisulfate, it is used in place of the sulfuric acid. The bisulfate is best used to distill with the nitrate. One mole of bisulfate to one mole of nitrate will give one mole of nitric acid, where as sulfuric acid will give two.
Steve[/size]

So if we use bisufate w/nitrate, there will be no sulfhate crystals @ the end of the distilling? Or, we just get a better nitric? 
I'm gett'n ready to distill nitric & need the updated method. Please direct me to the posts.

Thanks!
philddreamer_


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## lazersteve

philddreamer said:


> So if we use bisufate w/nitrate, there will be no sulfhate crystals @ the end of the distilling? Or, we just get a better nitric?
> I'm gett'n ready to distill nitric & need the updated method. Please direct me to the posts.



No, there will be left over sulfate. Bisulfate forms a combination of sulfuric acid and sodium sulfate when water is added. This is where the acid comes from. The left overs are exactly the same as the sulfuric acid reaction.

Steve


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## philddreamer

Thank you Steve!

Is there a post with a diagram of what the set-up for distilling looks like. From what I've read, I have a general idea, but better safe than sorry.
I don't want to use ware not suited for the process.

phil


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## lazersteve

philddreamer said:


> Thank you Steve!
> 
> Is there a post with a diagram of what the set-up for distilling looks like. From what I've read, I have a general idea, but better safe than sorry.
> I don't want to use ware not suited for the process.
> 
> phil



All glassware distillation rig with water cooled condenser.

Simple Distillation Apparatus

Steve


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## philddreamer

Excellent!

Thank you Steve.

Phil


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## nimrood

lazersteve said:


> stihl88 said:
> 
> 
> 
> Am i missing something, wheres the Sulfuric Acid? This is great news for me because Sulfuric Acid is hard to get here in Australia.
> 
> Steve, can i substitute Sodium Nitrate for Potassium Nitrate instead?
> 
> And can i pickle my silver in the Sodium Bisulfate also?
> 
> 
> 
> 
> The sodium bisulfate is used in place of sulfuric acid.
> 
> Bisulfate in water can be used as a substitute for dilute sulfuric acid in many instances and should work for pickling gold.
> 
> The bisulfate provides the acidic hydrogen needed to convert the sodium nitrate into nitric acid.
> 
> I have not tried this reaction with potassium nitrate. Give it a try and let us know what you find.
> 
> Steve
Click to expand...


hi. this is my first post to the forum. i've been lurking and reading for several weeks and finally created an account a few days ago.

i hail from georgia, the nw-atlanta-metro area. one might think it wouldn't be difficult to find a local supply of sodium nitrate in a southern farming state.... but i've looked all over and can't find a reasonably close local supply. KNO3, however, is all over the place. i didn't see anyone respond regarding the substitution of potassium nitrate for sodium nitrate in the bisulfate/nitrate cold recipe. so, i'm giving it a go!

based on what i've read, i made up the following mixture:
1) 108g NaHSO4 dissolved in 150ml of water @ ~85-95C (sol. vol. increased to ~200ml)
2) dissolved 77g of KNO3 into the NaHSO4/H2O solution @ ~85-95C (sol. vol. increased to ~250ml)
3) filtered hot solution into a long neck, flat-bottom 250ml flask
4) stoppered the flask and put it in the freezer (about -17C to -15C)

i checked the solution about 3.5hrs later and noticed a fair amount of long clear crystals. i decanted, measured (~125ml), and tested the solution on a piece of copper. i didn't observe an immediate reaction w/ the copper as i expected (maybe it was too cold?). crystals appeared to still be forming on the surface of solution, so i popped it back in freezer for another 30min.

i checked the solution again, measured it (~100ml), and i am performing another copper test. this time i will let the copper test sit outside to warm up. i lost 25ml of solution in about 30mins, so i decided to decant it and put the flask in the refrigerator which is about 1-2C. the color of the solution is clear with a very faint amber tint, and it does not have a familiar odor (not much of an odor at all, actually)...at least not as cold as it is right now.

at the time of this posting, still no reaction with the copper.... so must come to one of these conclusions: (a) KNO3 isn't a good/valid substitute for NaNO3; (b) i didn't do something correctly; (c) it produced a very very weak nitric.


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## jimdoc

Is this place near you? They ship if not, I have ordered from them.

http://www.maconfeedandseed.com/product_info.php/products_id/103

Jim


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## nimrood

jimdoc said:


> Is this place near you? They ship if not, I have ordered from them.
> 
> http://www.maconfeedandseed.com/product_info.php/products_id/103
> 
> Jim



i consider macon an unreasonable distance--about 1.75hrs drive south of my location. i don't think my wife would tolerate that kind of day trip. 8) however, we do go through macon when we go to visit the in-laws deep south GA, but there's no telling when the next trip will be as i don't particularly like my in-laws!


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## nimrood

nimrood said:


> based on what i've read, i made up the following mixture:
> 1) 108g NaHSO4 dissolved in 150ml of water @ ~85-95C (sol. vol. increased to ~200ml)
> 2) dissolved 77g of KNO3 into the NaHSO4/H2O solution @ ~85-95C (sol. vol. increased to ~250ml)
> 3) filtered hot solution into a long neck, flat-bottom 250ml flask
> 4) stoppered the flask and put it in the freezer (about -17C to -15C)
> 
> i checked the solution about 3.5hrs later and noticed a fair amount of long clear crystals. i decanted, measured (~125ml), and tested the solution on a piece of copper. i didn't observe an immediate reaction w/ the copper as i expected (maybe it was too cold?). crystals appeared to still be forming on the surface of solution, so i popped it back in freezer for another 30min.



UPDATE: i tested the solution some more this morning and had a reaction with copper after applying heat. so the conclusion is i made a very very weak nitric by substituting KNO3. i wondered to myself "maybe must not be a 1:1 relationship here." a few calculations later, and it appears i didn't use enough KNO3:

77g KNO3 = 0.761 moles
77g NaNO3 = 0.906 moles

therefore: 91.5g of KNO3 == 77g of NaNO3.... time to try this again with the new formula.


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## GOLDMAN1234

I have dissolved roughly 30 cpu in a 3 -1 mixture of hydrocloric and nitric acid,after 2 days the good pins have not fully dissolved,which acording to my guide the should have ,what should my next stage be i have been told to add 100ml of AR to strip the plating of the gold pins.NEED HELP GUYS PLEASE PLEASE PLEASE


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## Harold_V

GOLDMAN1234 said:


> I have dissolved roughly 30 cpu in a 3 -1 mixture of hydrocloric and nitric acid,after 2 days the good pins have not fully dissolved,which acording to my guide the should have ,what should my next stage be i have been told to add 100ml of AR to strip the plating of the gold pins.NEED HELP GUYS PLEASE PLEASE PLEASE


Lets start with what you've been reading. Has it been Hoke? Do you understand the ramifications of using AR and not completely dissolving all of the metal? 
Do you know what stannous chloride is, and for what it is used? 

We can help you with your project, but it's more important, right now, that you help yourself by addressing some of the basics of refining. Don't discard anything---and if you have a safe place to store your material while you do some reading, do so. Remember, the fumes are quite corrosive, so don't store anything in your garage or anywhere you have things of value that can rust. 

If you don't know about Hoke's book, do a search for Palladium. In his sig line you will find a link that permits a download of Hoke's book. 

Read Hoke. 
Read Hoke again.
Read Hoke until you understand what she teaches. At that point in time, you shouldn't have any questions about what's going on with your project, and if you do, we'll be here for you. 

Harold


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## dtectr

Harold_V said:


> If you don't know about Hoke's book, do a search for Palladium. In his sig line you will find a link that permits a download of Hoke's book.
> 
> Read Hoke.
> Read Hoke again.
> Read Hoke until you understand what she teaches. At that point in time, you shouldn't have any questions about what's going on with your project, and if you do, we'll be here for you.
> 
> Harold


I might add here - take the time to conduct her Familiarization Experiments to the extent possible for you. Nothing is actually lost if you follow the instructions, & based on my own brief experience, it can literally save you _months_ of stumbling around in the dark.
dtectr


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## ExNuke

I haven't posted before on the Forum but I've been reading it extensively for several months now. Is this thread too old to hope for a reply? My question is would lazersteve's recipe work ok for distilling and would that give Nitric acid that was suitable for silver without giving me a bunch of silver chloride? I'm only doing small batch hobby level recovery and refining of silverand the cost of commercial Nitric Acid is a pain in the wallet.


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## maynman1751

Yes, Lazersteves recipe will work if you distill first. It must be distilled in order to work properly with silver. Just make sure to use all safety precautions when distilling and using Nitric. You are new here and need to understand the dangers of using these hazardous chemicals. Be safe!!!!!


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## ExNuke

maynman1751 said:


> Yes, Lazersteves recipe will work if you distill first. It must be distilled in order to work properly with silver. Just make sure to use all safety precautions when distilling and using Nitric. You are new here and need to understand the dangers of using these hazardous chemicals. Be safe!!!!!



Thanks for the reply. I understand the safety caution and need for it, I'm new to refining but not to working with less than safe chemicals and use a pretty complete suite of safety gear. Other than the cost of Nitric Acid my biggest problem is finding enough scrap silver to justify setting up my cell, So far I've produced ~750 grams of pretty nice crystal from salvaged electrical contacts with a stainless bowl cell , so far my biggest expense with refining has been a liter of HNO3 with the Hazardous Shipping Fee. The rest of my gear has been re-purposed or home made, that is half the fun.


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## JRB3

And IF I could find a source of nitric that did not cost an arm, leg, and other body parts I am fond of I would certainly not bother making it.

Virgil 

I also am a Noobie to this sight and haven't been able to walk away from it since I recently joined. I had some info for you rearding to buy or to make nitric acid. So not sure what a body part goes for on the black markrt nowadays ( whether it's your favorite one or not ) but I just purchased a 1L of 50% for just over 70.00 with tax and shipping to my door the GRAINGER. 
I'm not thrilled with having it delivered to my door, as well as a paper trail also leading to my door, not that I'm doing anything illegal I just don't care for everyone knowing my business 24/7. I had already spent that amount getting ready to make my own etc when I came across it in their catalog ( BOOK , if I added 15 more dollars I could have bought 2.5L but it comes in a wine box looking container, at least the one I bought comes in the appropriate amber bottle. The larger amount compelled me to buy amber bottles to house that amount of Acid which would double the cost. So if you have the glass or can see using that amount in 24 months it really is cheap. They also sell a 500 ml for around 50 out the door. Oh last catch 2 week wait time for delivery at least out here to Ca., it comes from idaho so shipping time could be less if live closer than I do.
So thats it I am about to go make my own since I can't seem to wait for the snail mail to arrive. Thank you everybody who has made this forum and site what it is today.
Lastly I do alot of reading on the computer no so much blogging or answering topic questions, So I probably didn't do this right and if that's the case allow me to apologize in advance and please excuse my mistakes - Jim


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## ExNuke

New Question. How does anyone go about cleaning the salts out of your reaction vessel after cooling? After pouring off the newly made acid the salts are like a rock, I'm sure people aren't just throwing away glassware. ( The Acid works fine! ) I found Hy-Yield Nitrate of Soda at the local garden center @ $9.00 for 4 pounds. Even with Walmart Drain Cleaner sulfric acid it's a lot cheaper to make HNO3 than to pay the Hazmat shipping fee.


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## Barren Realms 007

ExNuke said:


> New Question. How does anyone go about cleaning the salts out of your reaction vessel after cooling? After pouring off the newly made acid the salts are like a rock, I'm sure people aren't just throwing away glassware. ( The Acid works fine! )



Hot water works to redissolve it.


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## ExNuke

Barren Realms 007 said:


> ExNuke said:
> 
> 
> 
> New Question. How does anyone go about cleaning the salts out of your reaction vessel after cooling? After pouring off the newly made acid the salts are like a rock, I'm sure people aren't just throwing away glassware. ( The Acid works fine! )
> 
> 
> 
> 
> Hot water works to redissolve it.
Click to expand...


Thanks BR, I just discovered that myself. I was just in to big a hurry, a few minutes on the hot plate and it dissolved, cold (room temp) water didn't appear to touch it. When all else fails, apply heat. Napalm or a flame thrower is a little over the top though.


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## upcyclist

ExNuke said:


> New Question. How does anyone go about cleaning the salts out of your reaction vessel after cooling? After pouring off the newly made acid the salts are like a rock, I'm sure people aren't just throwing away glassware. ( The Acid works fine! ) I found Hy-Yield Nitrate of Soda at the local garden center @ $9.00 for 4 pounds. Even with Walmart Drain Cleaner sulfric acid it's a lot cheaper to make HNO3 than to pay the Hazmat shipping fee.


IIRC, they were water soluble. Hot water.

Edit: On the cheaper to make front, it all depends on what your time is worth. For now at least, I'm inclined to agree, at least for when I need just nitric. I think I'll stick with purchased nitric for AR, at least for final refinings (may use Poor Man's for first drop).


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## HizHiNess

Hi Everyone,

I just joined the forum and this is my first reply. Revering to lazersteve's cold nitric acid recipe here are a few suggestions. The process outlined takes sodium nitrate dissolves it in very hot water, adds sulfuric acid then cools the solution to precipitate the sodium sulfate from the solution. What remains is a solution of nitric acid that is contaminated with a little sodium sulfate.

Equation (not balanced)

NaNO3 + H2SO4 = Na2SO4 + HNO3

The process of the reaction goes almost to completion only when the solution is cooled to 0 degree C. The concentration of nitric acid produced is dependent upon the degree of completion of the reaction and the concentration of sodium nitrate in water that one begins with. If one uses 100 ml of water to dissolve the sodium nitrate and the reaction was 100 percent then the nitric acid formed will still be dissolved in 100 ml of water. Achieving azeotrope concentrations of nitric acid will require distilling the mixture.

However, one can tweak the basic reaction by substituting other nitrates for the source of the NO3 in nitric acid. A great help is the Solubility table From Wikipedia, the free encyclopedia. Here you can find the solubility of many different compounds at various temperatures. An ideal nitrate would be extremely soluble in very little water and the metal carrying the nitrate, its sulfate should be virtually insoluble. The reaction would go virtually to completion and the nitric acid produced would be minimally diluted with water. 

Unfortunately, no such ideal metal nitrate exits, but some of them make better candidates than others. Here are my suggestions.

Strontium nitrate
Potassium nitrate

Over 95 grams of Strontium nitrate will dissolve in 100 ml of water at 80 degree C. When sulfuric acid is added (use extreme care, great amounts of heat is produced when adding sulfuric acid to water, especially when the water is close to boiling, splattering can occur, add the sulfuric acid slowly) strontium sulfate will be produced that is virtually insoluble thus driving the reaction to completion (solubility about 0.015 grams per 100 ml of water). The strontium sulfate precipitate can be filtered out of the solution leaving a solution of almost pure diluted nitric acid.

Almost 200 grams of potassium nitrate will dissolve in 100 ml of water at 90 degrees C. The potassium sulfate produced can be made to precipitate by cooling the solution to about 5 degree C or lower. The advantage of using potassium nitrate is in the concentration of the initial solution of potassium nitrate in water and the fact that the potassium sulfate produced is less soluble in water (higher temperatures).

Sources of materials

Hobby Chemical Supply for potassium nitrate (5lbs - $15.00 10 lbs. - $25.00)
for strontium nitrate (1lbs - $5.00)
for sodium nitrate (1lbs - $5.50)

Lowes Home Improvement Plumbing Department professional drain cleaner Sulfuric Acid 93% (1quart bottle - about $10.00)


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## HizHiNess

Hi Again,

Just wanted to post another suggestion. 

Calcium Nitrate, available at Amazon at about $7.50 for a 5.00 lbs bag would also work very well. Ca(NO3)2 is extremely soluble in water. Large amounts of it can be dissolved (more than 100 grams in 100 ml of water). When Sulfuric Acid is added to a saturated solution of Calcium Nitrate, a precipitate of Calcium Sulfate hydrate will form. Only 0.265 grams or less of Hydrated Calcium Sulfate will dissolve in 100 ml of water. In addition, the solubility of Hydrated Calcium Sulfate is uniform over the range of liquid water. This will drive the reaction of adding Sulfuric Acid to a saturated solution of Calcium Nitrate highly to the right (completion). The Nitric Acid produced can be easily filtered from the Hydrated Calcium Sulfate. Since the solubility of Hydrated Calcium Sulfate is uniform over the temperature of liquid water, cooling of the solution is not needed.

See my previous post for sources of chemicals and other suggestions.


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## Topher_osAUrus

I dont think i would use strontium personally, what would you do with the waste?

Potassium nitrate i would, but only if my local shop was out of sodium.

Calcium I would stay away from, unless you are using it to recycle the sodium sulfate from the last batch. As calcium sulfate is VERY hard to get all of your nitric out of.
But, i guess there are a whole bunch of things you can use the plaster byproduct for.

There are a couple threads that cover these issues much better than i can with a couple quick sentences.

Stay safe.

Toph


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## Shark

> The Nitric Acid produced can be easily filtered from the Hydrated Calcium Sulfate.



I would like to see or hear how that could be done, short of distilling it off. My experience with calcium nitrate was that it produced a very strong acid, but filtering was practically impossible by gravity filtering alone. Under vacuum filtering there was some still left behind trapped in the "plaster". Potassium nitrate or sodium nitrate has always worked well and performed well for me. I have a distilling rig now, but still haven't used it, might be getting time to give it a test run soon.


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## ExNuke

About distilling the product from the Cold Nitric Acid Recipe. I previously made a small batch with good results but I'm only hobby level playing with silver and have run out of scrap feed stock. Does anyone know if a Stainless Steel distilling rig would have any problems? I recently found a stainless still that I made a long time ago to distill water, it would be a lot less fragile than an all glass rig and I already have it, only need a couple of viton O rings to put it back in service.


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## Ckestrada

If the end result is weak dilute nitric acid could one heat or evaporate to get a higher concentration?


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## upcyclist

Ckestrada said:


> If the end result is weak dilute nitric acid could one heat or evaporate to get a higher concentration?


Personally, I don't like to evaporate/heat/distill nitric unless necessary. 

Assuming you've used concentrated sulfuric, reacted fully, and followed the directions, you'll get decent strength nitric. You can use it straight when protocols on here call for a 50/50 mix of nitric and water. Heck, even if it's quite dilute, there's still uses for dilute nitric in our work*, so you could just leave it alone, use it for those things, and take another shot at the cold nitric procedure.

*For example, last night I used a stirring rod to break up chunks of cement silver that I had been drying. I also had moved a second batch into the same drying dish (same feedstock). Of course, the fine silver powder stuck to everything. So I rinsed the rod & jar in dilute nitric into the current batch of nitric digest. Easy peasy.


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## HizHiNess

Hi Virgil,

I think I may have a reason and a solution for your problem of not being able to dissolve the 170 grams of sodium nitrate in 100 ml of water. You mentioned that you boiled the water, measured off 100 ml, then added the sodium nitrate, and stirred.

Sodium nitrate is similar to ammonium nitrate in as much as both compounds absorb heat as they dissolve. The water was at 100 C when you poured it but when you started to dissolve the sodium nitrate, the temperature quickly fell. Sodium nitrate has a steep solubility curve. At lower temperatures much less can go into solution.

The solution is to add the sodium nitrate and then put the container (heat resistant glass) back into the microwave and carefully heat the sodium nitrate solution up to boiling again. Almost all of the sodium nitrate will go into solution.

Now comes the tricky and possible dangerous part. Immediately remove the dissolved sodium nitrate from the microwave and very carefully add the sulfuric acid. Add the acid in small increments. The resulting solution will boil and splatter (use a high walled container safety glasses and acid resistant clothing). 

When all the sulfuric acid has been added, immediately stirr the resulting solution. Cap the solution and let the solution return to room temperature. Place the solution container into a zip lock plastic bag and place into the freezer.

When the temperature is at equilibrium, remove from freezer, and pour off or filter the thick liquid. This is the nitric acid you have made. The crystals at the bottom and sides of the container are the sodium sulfate that precipitated from the solution at the freezer temperature. The removal of the sodium sulfate pushes the reaction to produce the nitric acid.


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## HizHiNess

Hi Everyone, 

My suggestions for using other metallic nitrates (Strontium Nitrate, Calcium Nitrate) for making nitric acid from sulfuric acid was to bypass the need to freeze the reacted products to obtain the nitric acid. Freezing is required when one reacts either sodium or potassium nitrate with sulfuric acid.

You are correct, Shark when you stated that calcium sulfate does not filter well (my error). However, if a small centrifuge is available, one should be able to separate most of the nitric acid from the calcium sulfate.

Here are some questions for the group.

Which nitrate (sodium nitrate or potassium nitrate) produces the strongest nitric acid using Lazersteve's cold nitric acid recipe? 

Which nitrate (sodium nitrate or potassium nitrate) produces the easiest separation of the produced potassium sulfate or sodium sulfate from the nitric acid produced?


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## TreySeaJax

Hi,

First, I want to thank this board for encouraging me to study the posts. Read Hoke's book then re-read it several times. 

Some day soon I am going to purchase some lab grade nitric acid. I hope to one day distill some super pure nitric. For now I am making my own with varied results.

Steve, I tried the recipe you posted with potassium nitrate. I used the Spectracide granules. I measured 220 grams and dissolved on low heat in 100 ml distilled h2o. Once dissolved, added 140 g drain opener h2so4.

I put it in the freezer and checked every 15 minutes. Maybe I should have pulled it earlier but it went from liquid to full of solid, potassium sulfate right? The liquid was hard to pour and filter. The yeild was about 70 ml that eventually came through.

So, there may be more nitric trapped inside the soild form. I am going to try to bust it up and dump it in the filter to see what else will come out.

The part I am very thankful for is, that is a much stronger nitric than what I usually make. Even if the 70 ml is all to expect, I will do it again. The whole process took less than an hour and a half.

Thanks for taking the time to help others!


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