Can the copper nitrate solution , after cementing out silver be reused a second time to dissolve silver or do you have to recover the nitric acid by distilling the copper nitrate solution w/ sulfuric acid ?
Reuse copper nitrate
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Looking through my notes, using HCl To precipitate out silver as silver chlorite and nitric acid .
Both Omegageek64 and Nurdrage have YouTube video's on recovering nitric acid from used copper nitrate waste. This procedure requires knowledge on distillation, I wouldn't attempt it unless you have some distillation experience. The nitric acid that comes over will be a higher concentration, that higher concentration must be respected.....not only is it a fire hazard, but it can nitrate certain materials and make them very energetic.
Martijn
Well-known member
You can use it to make silver nitrate for your silver cell. Look at this post from @lazersteve. It really is a great discovery that saves a lot on nitric use.
Thread 'Processing Sterling Silver without nitric acid' Processing Sterling Silver without nitric acid
Thread 'Processing Sterling Silver without nitric acid' Processing Sterling Silver without nitric acid
Martijn
Well-known member
This method allowes you to skip the first digestion in nitric. Treat the sterling in the silver cell and revive the electrolyte once it's too polluted.
Martijn
Well-known member
He does produce concentrated fuming nitric which will ignite a nitrile glove.
Be sure when making statements about risc levels. Concentrated acids can behave completely different from their diluted versions.
lazersteve
Well-known member
I see no need to waste the time and energy distilling off the nitric acid when it's actually the nitrate ion in solution that we are needing. The only need for proper nitric acid would be if you wanted to digest pure silver to make silver nitrate, which is not a requirement using the copper nitrate cell as described in my post under discussion. In situ reactions that mimic the exact behavior of proper nitric acid are perfectly acceptable in refining as long as the end result is a product of sellable purity that is obtained with the least amount of labor and overhead costs.
In my daily refining work I use only nitrate salts and have no issues with refining sterling, inquarts, cell, and other dirty Ag sources. I have proper nitric acid on hand if I need it in my lab.
Just because one CAN distill nitric acid from copper nitrate does not mean that you necessarily should for refining purposes. You can read my comments in NR video you are referring to and get more insight to my mindset.
I posted my copper nitrate cell for sterling use on July 4, 2008 and have been researching and improving on the idea of focusing on copper as a transport mechanism for the nitrate ion. I utilize this concept up to this very day in my refining work. It is a fundamental idea to grasp when refining, the transport of the nitrate ion, in my humble opinion
Steve
Last edited:
Steve
First of all ,thanks for taking the time to respond just a couple of things. After watching Mbpub”s video ( where he evaporated the nitrate salt then distilled ) I think is an option to recover the nitrate reducing my waste stream.
After processing Sterling silver I seamed to have accumulated 1/2 gallon of copper nitrate couple of gallon of diluted copper nitrate from washing the cementing silver.
I was really interested in that silver cell using spent copper nitrate and melted Sterling silver so if it’s ok w/ you once I get the granite block and make a mock up . Would you mind as time permits giving any suggestions or pointers please.
P.S
This is just a hobby for me it keeps me from having to do yard work sometimes and is a nice distraction .
Jeff
First of all ,thanks for taking the time to respond just a couple of things. After watching Mbpub”s video ( where he evaporated the nitrate salt then distilled ) I think is an option to recover the nitrate reducing my waste stream.
After processing Sterling silver I seamed to have accumulated 1/2 gallon of copper nitrate couple of gallon of diluted copper nitrate from washing the cementing silver.
I was really interested in that silver cell using spent copper nitrate and melted Sterling silver so if it’s ok w/ you once I get the granite block and make a mock up . Would you mind as time permits giving any suggestions or pointers please.
P.S
This is just a hobby for me it keeps me from having to do yard work sometimes and is a nice distraction .Jeff
lazersteve
Well-known member
No worries. I'm here to help. If you have a Cu(NO3)3 saturated solution you can check specific gravity and add calculated amount amount of concentrated H2SO4 to rejuvenate your HNO3 and proceed as desired with the nitric acid with trace CuSO4 after freezing out the CuSO4 crystals. Saturation is key to the success of this process. The resulting nitric can be used in any reaction where nitric acid is required. Keep accurate records of molarity in your lab book and keep solutions concentrated.
Steve
Steve
SG solution 1= . 088
SG solution 2= .042 ( rinse water)
need to evaporate both solutions
What is the target SG of Cu(NO3)2 ? 1.15g/ ml ?
So when freezing the crystals out supersaturate then cool?
Sorry it took so long to respond
SG solution 2= .042 ( rinse water)
need to evaporate both solutions
What is the target SG of Cu(NO3)2 ? 1.15g/ ml ?
So when freezing the crystals out supersaturate then cool?
Sorry it took so long to respond
Is the cell your using similar to the one one pages 254-258 “processes used by professional refiners”/ C.M Hoke ?
What kind of numbers are these?
It have to be 1.088 and 1.042 or it will be gaseous?
This is weird I thought I corrected/ edited those number shortly after posting. 1.088 and 1.042 is correct. I am currently evaporating the solutions down . But what is the target molar numbers of solution for the cell ?
lazersteve
Well-known member
Cu(NO3)2*3H2O solubility is 3810g/L @ 40C according to wiki or 15.77 M of Cu(NO3)2 equal to 31.53 moles of available nitrate.
The Copper nitrate cell operates at 6 moles per liter according to the patent if my memory serves me correctly.
Steve
The Copper nitrate cell operates at 6 moles per liter according to the patent if my memory serves me correctly.
Steve
Thanks Steve
So 1M Cu ( NO3)2. = 187.558 g/M X 6
equals 1125.348 g/mol
Move three places to convert grams to liters
1.1253 would be the specific gravity ?
Diluting solutions, found the copper mesh graphite on the way working on mock up.
P.S.
I’m a little embarrassed about Wikipedia info and I also didn’t know there was patent on this .
So 1M Cu ( NO3)2. = 187.558 g/M X 6
equals 1125.348 g/mol
Move three places to convert grams to liters
1.1253 would be the specific gravity ?
Diluting solutions, found the copper mesh graphite on the way working on mock up.
P.S.
I’m a little embarrassed about Wikipedia info and I also didn’t know there was patent on this .
It is not gram per mol, mol is weighed in grams.
M is mol per liter.
Why are you focussed on the SG?
After running the cell for a wile it is not correct anymore since there will be contaminants.
For starting, it is sufficient with the weight of the Copper Nitrate.
Bragbasil,
I as taught if your going to do a job do it right the first time so I was looking for a good starting point . I think I am on track.
Molar mass of Cu (NO3)2 = 187.5558 g/mol
6M = 1123.38 g/mol
One gram same as one mL right
So, move three place to left
1.123 SG
I as taught if your going to do a job do it right the first time so I was looking for a good starting point . I think I am on track.
Molar mass of Cu (NO3)2 = 187.5558 g/mol
6M = 1123.38 g/mol
One gram same as one mL right
So, move three place to left
1.123 SG
Martijn
Well-known member
No. 6M= 1123.38gr/ 6mol.
Specific gravity has nothing to do with mol weight. It influences the density of a substance, with exceptions. Heavy atoms tend to be dense but not all.
Mol weight is the weight of a certain fixed amount of atoms of a substance.
For Hydrogen that amount of atoms weigh about 1 gram.
Specific gravity or relative density is how much a fixed volume of a substance weighs compared to the density of water. Is says nothing about the molweight.
Mol is used to calculate and so balance chemical reactions in combining or splitting compounds and elements. Equal amounts of atoms to react with each other.
Specific gravity of copper nitrate is 3.05gr/ml.
A 6M solution means you have 6M of salts dissolved in water, making 1 liter in total.
Hope this helps explain things for you.
Martijn.
thanks Martjn
I’m going to work on my lawnmower and digest this and rework the solution on paper not head
I’m going to work on my lawnmower and digest this and rework the solution on paper not head
