Concentrate Nitric Acid ?
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zuberb,
If you used sodium nitrate
170g NaNO3 (powder)
100 ml water (liquid)
56 ml of 98% H2SO4 (liquid)
At most you should have close to 159 ml of liquid (nitric acid), and sodium sulfate salts, and these salts would also hold some of that liquid involved in the reaction.
How did you end up with 250ml liquid?
Where did all of the extra liquid come from? It is probably why you see the cloudy solutions, also if using city water you may have introduced some chlorides from chlorine in the water.
If you used sodium nitrate
170g NaNO3 (powder)
100 ml water (liquid)
56 ml of 98% H2SO4 (liquid)
At most you should have close to 159 ml of liquid (nitric acid), and sodium sulfate salts, and these salts would also hold some of that liquid involved in the reaction.
How did you end up with 250ml liquid?
Where did all of the extra liquid come from? It is probably why you see the cloudy solutions, also if using city water you may have introduced some chlorides from chlorine in the water.
zuberb
Well-known member
- Joined
- Jan 4, 2012
- Messages
- 47
I'm going to give this another shot when I get the time. I could have swore I measured the water exact, unless my flask is graduated in something other than ml. It's possible I inadvertently used double the water. I use distilled water for all of this stuff because our tap water is loaded with contaminants.
Now that you mention it, there's no way it could have increased in volume unless it pulled 100ml out of the air (not likely).
Now that you mention it, there's no way it could have increased in volume unless it pulled 100ml out of the air (not likely).
zuberb
Well-known member
- Joined
- Jan 4, 2012
- Messages
- 47
I ran another batch, and this time got closer to the right volume of liquid back. It was right at 150ml. I tested it immediately on a tiny piece of copper in a test tube (while still cold). I did not notice a reaction at all other than the fact that the piece of copper wire was immediately coated with a white film. The acid did not seem to attack the copper. This acid isn't supposed to be strong enough to cause passivation right?
I was assuming there was just too much salt still in solution (although it was clear with a real light green tint). I placed it back in the freezer for another night and it did in-fact precipitate more salts out of the solution. When I tested on copper again, it was more reactive than the first time, but still caused a white film to cover the copper. Is it possible that there is still a significant amount of salt in this acid and that is what is coating the copper? I added just a little heat and it started to react more. This acid appears to be significantly weaker than the nitric I've made simultaneously using the NurdRage method in a separate set of glassware.
Unfortunately, I only own one amber glass bottle suitable for nitric storage, so I dumped the weaker acid in with my stronger stuff. As soon as I did it, I realized I should have tested both acids separately for approximate concentration. And also that I had probably just contaiminated my good acid with this salty stuff. Piss poor planning on my part.
The next morning, I noticed the tiny amount of acid in that test tube with a piece of copper wire had grown crystals at room temp overnight. Enough crystals to completely occupy the same volume as the acid. I couldn't even see the copper, cause it was buried in these salty looking crystals. Now I realize that the solution still contained more salt. Ughhhh.
Next time I get a chance to try both methods again, I'll try to figure out the concentrations I'm getting from each method. I'm also going to leave the cold solution in the freezer for at least three days before pouring it off. I followed the recipe, but it didn't say how long to leave it in the freezer. I believe I'm either taking it out way too soon, or my freezer isn't quite getting it down to -5.
I was assuming there was just too much salt still in solution (although it was clear with a real light green tint). I placed it back in the freezer for another night and it did in-fact precipitate more salts out of the solution. When I tested on copper again, it was more reactive than the first time, but still caused a white film to cover the copper. Is it possible that there is still a significant amount of salt in this acid and that is what is coating the copper? I added just a little heat and it started to react more. This acid appears to be significantly weaker than the nitric I've made simultaneously using the NurdRage method in a separate set of glassware.
Unfortunately, I only own one amber glass bottle suitable for nitric storage, so I dumped the weaker acid in with my stronger stuff. As soon as I did it, I realized I should have tested both acids separately for approximate concentration. And also that I had probably just contaiminated my good acid with this salty stuff. Piss poor planning on my part.
The next morning, I noticed the tiny amount of acid in that test tube with a piece of copper wire had grown crystals at room temp overnight. Enough crystals to completely occupy the same volume as the acid. I couldn't even see the copper, cause it was buried in these salty looking crystals. Now I realize that the solution still contained more salt. Ughhhh.
Next time I get a chance to try both methods again, I'll try to figure out the concentrations I'm getting from each method. I'm also going to leave the cold solution in the freezer for at least three days before pouring it off. I followed the recipe, but it didn't say how long to leave it in the freezer. I believe I'm either taking it out way too soon, or my freezer isn't quite getting it down to -5.
Dravin
Member
hi guys, i was watching all of the different ways in making Nitric Acid. What are your views on 100mls of Hydro peroxide heating it like lazer steves water in coffee pot then dropping the NaNO3 and letting it disolve in the boiling peroxide then adding the 56ml of Sulfurice Acid? Would that make a more potent Nitric Acid?
Geo
Well-known member
Peroxymonosulfuric acid is created by reacting peroxide with sulfuric acid. this is a highly unstable compound that when mixed with an organic can explode. of coarse the reagents are concentrated sulfuric and 50% hydrogen peroxide but even the 3% may create a weaker form. some of the chemicals we use work good for what we use them for but when you mix chemicals outside of the guides found here may be trouble. there may be little or no danger involved in what you propose but the reactions i mentioned is a fact and i would err on the side of caution.
http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=37&t=1403&view=print
Dravin
Member
Geo said:
WOW, lol thanks for the reply, i almost did it yesterday but decided not to untill i heard back from the wise.
thanks again 8) :lol:
lazersteve said: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 recipe 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 ). :wink:
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)
-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 precipitate 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
Steve
Couldn't you just add 200gm k/170gm na to 150 ml of battery acid (35% sulfuric 65% water)? That seems like it would give you right around 100 ml water and 52ml 97.5% sulfuric acid which is the end result of all what you said.
The point of adding the water as a separate reagent is to guarantee that all of the nitrate is fully dissolved before adding the concentrated sulfuric acid.
Steve
Steve
lazersteve said: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 recipe 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 ). :wink:
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)
-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 precipitate 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
Steve
Hi all,
If I would make some of this Nitric Acid I know it is 50% can I use it to process some Sterling Silver? Do I need to add any H2O or use it as is since it not 67% Nitric Acid?
Jack
Hi,
The Sodium Nitre is Na2SO4 and you would use 170 gm Na. I watch the video how to make it and I don't think it talk about 202 gm K or did it and I miss it?
Edit this.
Just found out it is Potassium Nitrate so which is better to use?
Jack
The Sodium Nitre is Na2SO4 and you would use 170 gm Na. I watch the video how to make it and I don't think it talk about 202 gm K or did it and I miss it?
Edit this.
Just found out it is Potassium Nitrate so which is better to use?
Jack
The sodium nitrate is NaNO3 when mixed with sulfuric acid it makes nitric acid, the byproduct is sodium sulfate salts Na2SO4.
In laser Steve's formula above we use 170 grams of sodium nitrate, or if we use potassium nitrate KNO3 we use 202 grams.
For silver it would be best to freeze out as much of the sodium sulfate salts as you can, then distill the nitric acid, which will leave the remaining sodium sulfates behind, giving you a more pure 50% or so nitric acid, without the sulfate salts that would cause problems with your silver. you can dilute this down to about 35% HNO3 with water to dissolve your silver.
If it was a little more dilute I wouldn't worry, as with heat it will still dissolve your silver, and with heating it will concentrate the solution as the silver dissolves.
In laser Steve's formula above we use 170 grams of sodium nitrate, or if we use potassium nitrate KNO3 we use 202 grams.
For silver it would be best to freeze out as much of the sodium sulfate salts as you can, then distill the nitric acid, which will leave the remaining sodium sulfates behind, giving you a more pure 50% or so nitric acid, without the sulfate salts that would cause problems with your silver. you can dilute this down to about 35% HNO3 with water to dissolve your silver.
If it was a little more dilute I wouldn't worry, as with heat it will still dissolve your silver, and with heating it will concentrate the solution as the silver dissolves.
amosfolz
Member
Hello all,
I am wondering if anyone could instruct me on how to properly dispose of the leftovers when using LazerSteve's Cold Nitric Method. I have been searching for quiet a while now to no avail.
I am wondering if anyone could instruct me on how to properly dispose of the leftovers when using LazerSteve's Cold Nitric Method. I have been searching for quiet a while now to no avail.
I have read a bunch of the posts in this section, to date I have not used the recipe. One issue I have seen mentioned is the possibility of a beaker breaking while concentrating H2So4. So being who I am, I had an Idea that I believe can eliminate the danger. Place the beaker in a sand bath while boiling off excess H2o. The sand will distribute the heat evenly and allow for a slower and uniform cool down. It would take more time to heat it up but if safety is a priority it's worth it.
Just a thought, comments more than welcome.
Joe
Just a thought, comments more than welcome.
Joe
