Nitric acid production questions

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fivel_976

Well-known member
Joined
Apr 19, 2019
Messages
57
I have a few questions I'd like to get answers to before I start. First of all my set up will be simple distillation 1000ml boiling flask 500ml catch flask the setup came with a 200mm condenser I felt like I'd get more if I bought a 400mm so I did. I'll be heating this with a propane berner I use to use for lead smelting since it's an open flame I decided to go with a sand bath. My chemicals consist of spectracide and hi-yeald stump remover that I heated in distilled water and crystallized to purify it and rooto sulfuric acid drain cleaner my plain is to mix 400 grams of each and distill. My question is in a few you tube videos people heat this to different temps one guy says at 250 you distill 68% nitric and at 315 you get 95% nitric but others say heating this high runes it. I want to get the most that I can outa each batch and I also beleave the higher % the better as I won't need to stock pile mass amouts of acid just more water so I'm confused at what temp is gonna be the best yield. Also I. Wondering if I piggyback my liebig 200mm and 400mm condensers together will I net more acid as the fumes pass through. Thanks in advance for any advice
 
I have never used anything stronger than 67% although I have used some at less than that. Even at 67% I use 50/50 water to nitric most of the time. It will work fine on silver.

I don't recall off the top of my head right now what temps to distill it at (been a while since I made any) but 250 sounds way high. Like refining it needs time to come out right.
 
fivel_976 said:
I have a few questions I'd like to get answers to before I start. First of all my set up will be simple distillation 1000ml boiling flask 500ml catch flask the setup came with a 200mm condenser I felt like I'd get more if I bought a 400mm so I did. I'll be heating this with a propane berner I use to use for lead smelting since it's an open flame I decided to go with a sand bath. My chemicals consist of spectracide and hi-yeald stump remover that I heated in distilled water and crystallized to purify it and rooto sulfuric acid drain cleaner my plain is to mix 400 grams of each and distill. My question is in a few you tube videos people heat this to different temps one guy says at 250 you distill 68% nitric and at 315 you get 95% nitric but others say heating this high runes it. I want to get the most that I can outa each batch and I also beleave the higher % the better as I won't need to stock pile mass amouts of acid just more water so I'm confused at what temp is gonna be the best yield. Also I. Wondering if I piggyback my liebig 200mm and 400mm condensers together will I net more acid as the fumes pass through. Thanks in advance for any advice


why would you need that high nitric % ? you are not trying to make explosives are you?

for recovery/refining nitric azeotrope of 68% works fine
 
I just figured at 95% I could store less volume of acid and just use more water to get to 35% needed for silver
 
fivel_976 said:
I just figured at 95% I could store less volume of acid and just use more water to get to 35% needed for silver

You don't want to be making 95% Nitric. Stick to the lower concentration.
 
So to get 68% do I bring the boiling temp to 250 degrees Fahrenheit and hold the temp there until the sulfuric acid is almost gone? And will I benefit from running a longer condenser like butting my 400mm to the 200mm?
 
Fivel, you really need to study the process more before you jump into this. The questions you're asking show you don't understand it.

When you mix your nitrate salt with sulfuric acid, you end up with nitric acid and a sulfate salt, so you're not boiling the solution till the "sulfuric acid is almost gone".

95% nitric acid is horribly dangerous, and you can't get it by simple distillation regardless of the temperature.

When distillation is properly run, the length of the condenser is not important. You balance the temperature of the solution with the cooling capacity of the condenser. You won't "net more acid" by connecting two condensers together unless you're heating the solution too much with just one condenser.

Lazersteve and others have worked out the proper amounts of nitrate salt and sulfuric acid to use. Mixing 400 grams of each just wastes chemicals.

Don't rely on YouTube videos. Study what's been written here on the forum before you start mixing chemicals.

Dave
 
fivel_976,
The boiling point of the solution is determined by the concentration.
While the concentration will be determined by how much water is involved in the original solution being distilled.

Take a look at one method I like to make my nitric acid while recovering gold from electronic scrap in the same process, although it is not what you're trying to do, the information there will help you gain some understanding of distilling nitric acid.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=38&t=6199&p=54264&hilit=kill+two+birds+one+stone#p54264




Pure water has a boiling point of 100 degrees Centigrade.
20% Nitric acid boiling point of 103 degrees Centigrade and a density of 1.115 g/cm3.
30% HNO3 boiling point of 107 degrees Centigrade and a density of 1.180grams per cubic centimeter
50% nitric boiling point 116 degrees Centigrade and the density of 1.310
68% nitric is the azeotrope of nitric acid.
70% nitric boiling point 121 degrees centigrade and density of 1.482 g/cm3
90% nitric boiling point 102 degrees centigrade density 1.482 g/cm3
98% nitric acid boiling point 86 degrees centigrade density 1.503 g/cm3
 
Reading the linked post doesn't really help me flooding my mind with different processes only further confuses me. I just want to start by making my nitric acid by simple distillation I'm trying to do this whole process 1 step at a time all I want at this moment is to make a nitric acid capable of dessolving silver I just need a simple how to guide
 
fivel_976 said:
Reading the linked post doesn't really help me flooding my mind with different processes only further confuses me. I just want to start by making my nitric acid by simple distillation I'm trying to do this whole process 1 step at a time all I want at this moment is to make a nitric acid capable of dessolving silver I just need a simple how to guide

It may just be me but I'm struggling with how this post is worded.

Jon
 
I was just as confused when I first started. I also had no way to buy nitric acid and started by making some using the cold method as it could be done without distilling it. Knowing it would cost me a small bit of silver, I used it anyway to learn the process of cementing silver from a nitrate solution. I used the cold method several times until I had figured out some of the things I wanted to learn. Since it worked so well, I mixed up some of the chemicals for the cold method then distilled it as it was. While there are better ways, it done the job for quite some time until I became able to purchase a small amount that I am just now getting low on. Used right, 5 gallons of 67% nitric will process a good amount of silver, or in my case gold filled.

I am happy now, (not so much so back then) that it took me a while to study it out. Along the way I learned a few things that really became useful later and had no idea at the time I would ever need them. Refining is something that takes time, each step is whole process in its self. In the five or six years I have been doing this, even the things I have learned that didn't work were worth the time to learn.
 
Just looking for a simple guide to distilling nitric acid in a 1000ml set up . Like how much of each ingredient what temp how long to go for. If I can't find the answers I'll just put equal amounts of nitrate crystals and sulfuric acid and turn the heat up and let her buck see what comes out of the other end
 
Im well aware of the risks in the vary spot I smelted my lead will be the spot I do my distilling 18" wall fan that can move alot of air. Is you think hot acid is that dangerous try melting 3000+ lbs of lead wheel weights and poring 3000+ ingots id rather have hot acid on me then 700+ degree molten metal witch will bond to your skin not to mention the toxic fumes from melting it
 
fivel_976 said:
Im well aware of the risks in the vary spot I smelted my lead will be the spot I do my distilling 18" wall fan that can move alot of air. Is you think hot acid is that dangerous try melting 3000+ lbs of lead wheel weights and poring 3000+ ingots id rather have hot acid on me then 700+ degree molten metal witch will bond to your skin not to mention the toxic fumes from melting it

I'll get pilloried for this but I think your attitude sucks. I don't expect any support for my position but I'm going to say it as I see it.

You are here seeking knowledge. You are entitled to nothing. Knowledge is earned so go search and when you have looked at that knowledge and find a part you don't understand THEN come back and ask for clarity.

People supply information here out of the goodness of their hearts. No financial gain, nothing. You would be well advised to take note of that.
 
anachronism said:
I'll get pilloried for this but I think your attitude sucks. I don't expect any support for my position but I'm going to say it as I see it.

You are here seeking knowledge. You are entitled to nothing. Knowledge is earned so go search and when you have looked at that knowledge and find a part you don't understand THEN come back and ask for clarity.
I'll not put you in the stocks. I provided a couple of links that tried to communicate the same message.

I'd rather have the molten wheel weight metal hit me than fuming nitric acid.

Dave
 
700*+ molten lead worries you but boiling acid doesn't? You have a window box fan to blow air with? Where would you put the fan that would aid you the best?

Besides that you ask for a simple method to make nitric acid. I gave you a simple answer, the cold method. It worked for me and it worked very well. If I am going to research methods I most often prefer to waste my time searching for things that pertain to my needs first. I have much to learn yet and that is why I come here everyday. If I can help others in a small way, I will try repay those who taught me by trying to offer help to those with the very basic questions.

Here, I will hold your hand just once..........

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=19806&p=201787#p201643
 
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