# Old video - nitric, peroxide and ethylene glycol



## Bushka (Feb 23, 2013)

This may have been discussed before, but I thought I'd post it anyway. Is this person a member of this forum? It looks like a great way to dissolve silver, yet it doesn't seem to have become standard practice. I added a little household 3% peroxide to a small test batch of silver in nitric (which was nearly saturated with AgNO3) and the small amount of peroxide seemed to start the reaction back up a bit. I'm assuming there must be some downside to doing it this way:

https://www.youtube.com/watch?v=8PhE7GIUrxA

Dan


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## Marcel (Feb 24, 2013)

Bushka said:


> . I'm assuming there must be some downside to doing it this way:
> 
> 
> Dan



Why? A major difference between HCl f.i. and HNO3 is the 03! That makes the nitric an oxidizing acid and therefore very aggressive. Now if you introduce another form of oxygen, like with H2O2, it has the same effect. The used up oxygen gets "backup" by the oxygen from the H2O2 forming H2O/water plus free oxygen, ready for use with the reaction. The oxygen was used up by your first reaction, nitric was still there but could not do much without oxygen. Now that you added the H2O2/peroxide the reaction came back to life.
I read about the usage of glycol and that it will enhance the reaction. I forgot about the mechanism how it works, but there was even one patent based on it that I saw, so it seems to be confirmed and working. I tried it once with AP but could not see any big difference. But the right app should be a strong oxidizing acid such as nitric. 
I think both ways are really smart, because you reduce the amount of nitric beeing used in dissolving, which later will reduce problems with free nitric that has to be driven out, prior to precipitation. Instead of only adding nitric, maybe the last drops should only be H2O2..

Cheers


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## necromancer (Feb 24, 2013)

this original post was made by Noxx, does anyone have the link to the original post ??

thanks !!!


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## Bushka (Feb 24, 2013)

So what exactly is happening? My understanding is that the reaction is:

Ag + HNO3 ---> AgNO3 + NO2 + H2O (equation not balanced)

I found online that if the reaction is with dilute nitric acid, the NO2 gas does not form, instead forming nitrous acid, HNO2, which stays in solution. In my situation, I have been reacting with more dilute nitric acid as first tests since I'm new at this. I found that not so much of the red fumes were formed (I did get some early on). I thought that was because the reaction was so slow that I just couldn't see the red color (even with a plate of glass covering the top). It seems now that maybe I'm forming more nitrous acid in solution rather than as a gas.

I assume this means that the addition of peroxide adds an oxygen to the HNO2 forming HNO3, and causing the reaction to start back up. I added a little more 3% peroxide to my silver solution that seemed to have stopped, and it is still bubbling gently a couple of hours later.

Dan


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## mikeinkaty (Feb 24, 2013)

So, using those ingredients, what would the cost be to disolve 10 ounces of sterling using nitric that cost, say, $10 a gallon? I have no idea what antifreeze cost these days or what H2O2 - 35% costs. I presume this method requires no distilled water? Also that the silver would still drop in the usual ways? What about the residual waste - more or less toxic?

Mike


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## Bushka (Feb 25, 2013)

mikeinkaty said:


> So, using those ingredients, what would the cost be to disolve 10 ounces of sterling using nitric that cost, say, $10 a gallon? I have no idea what antifreeze cost these days or what H2O2 - 35% costs. I presume this method requires no distilled water? Also that the silver would still drop in the usual ways? What about the residual waste - more or less toxic?
> 
> Mike



I was looking around for 30% or 35% peroxide, and it is pretty expensive! I think the best price I saw was about $10 for only 100 ml. HOWEVER, some guy posted a Utube video of concentrating peroxide by heating it to just below boiling, say 99C for 4 or 5 hours. Keeping it below boiling minimized degradation of the peroxide. He said if you concentrate 3% household peroxide about 4 times, you will have about 30%. He reduced 1000 ml to about 300 ml and said if you want 30% then go down to 250 ml. The price of a whole quart of peroxide at 3% is only $1.99 at CVS pharmacy, and you might even find it cheaper. A quart is about 950 ml, reduced 4 times gives about 235 ml of 30% -- call it 200 ml of 35% -- for only $1.99. That vs $10 plus shipping for 100 ml. The only thing is I don't know what "stabilized" means on the bottle. I don't know if this chemical, or whatever it is, will interfere with silver refining.

Glycol can't cost much at the small quantities used.

I'm going to concentrate up some peroxide and see what happens. Just so you know, one of the companies I used to work for manufactured hydrogen peroxide. I didn't work with that process, so I don't know about stabilizers. I do know it was so concentrated that it would ignite anything spontaneously. Oh, some other guy on Utube put an open container of peroxide in his closet for several months and was left with a small amount of very concentrated peroxide (not smart). I think he blew something up with it.

Dan


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## butcher (Feb 26, 2013)

2 H2O2 + heat = 2H2O + O2
heat will drive the oxygen out of the water, so heating hydrogen peroxide would produce oxygen gas and water, heat it to vapor water and steam would mix with the oxygen leaving the vessel, I do not think evaporation could concentrate hydrogen peroxide, but a good way to destroy it.

If you need 32% H2O2, try the supplier for pools or spas look for soft swim.


Mario (a member of the forum) in the video above made that video from what he learned here on the forum. years ago, it was later determined glycol antifreeze was not needed for the reaction to work.


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## Geo (Feb 26, 2013)

evaporating H2O2 has been discussed before. if i remember correctly, the only safe way to do it was bubble dry air through it cold or to use a Desiccator. heating peroxide is a dangerous thing to do. once a certain concentration is reached, the H2O2 begins to fume. these vapors will explode on contact with the air.


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## Bushka (Feb 26, 2013)

Here is the video of the guy concentrating it. It does seem to get stronger, but by how much I don't know. Seems to me you just get too much volume of water if you just use 3%.

https://www.youtube.com/watch?v=pMLy5sVqX38


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## Bushka (Feb 26, 2013)

Geo said:


> evaporating H2O2 has been discussed before. if i remember correctly, the only safe way to do it was bubble dry air through it cold or to use a Desiccator. heating peroxide is a dangerous thing to do. once a certain concentration is reached, the H2O2 begins to fume. these vapors will explode on contact with the air.



I think like anything, if you overdo it then you're asking for trouble. My question is how effective is the mild heating method at getting to 30%, rather than breaking down the peroxide. The guy in the video definitely concentrated the peroxide, but he had no way to measure what he did other than qualitatively.


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## Geo (Feb 26, 2013)

Bushka, youtube is not the final say. do as you will but dont tell other members that have not studied the properties of hydrogen peroxide that heating and/or boiling peroxide is anything other than unsafe. do a wiki search or even a high school text book and gain some understanding. H2O2 is used as ROCKET FUEL. even though it is not combustible on its on, it will catalyze almost any type of metal. if you heated H2O2 and it concentrated to a certain percentage and there just happened to be a very small amount of left over metal in the container, BOOM, instant reaction. too, when H2O2 decomposes, what do you think it decomposes into? hydrogen and oxygen. two of the most explosive elements when combined.

youtube information should be considered inaccurate until it is confirmed here on the forum.especially if you want to use it on the forum as a "how to".


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## necromancer (Feb 26, 2013)

Geo said:


> heating peroxide is a dangerous thing to do. once a certain concentration is reached, the H2O2 begins to fume. these vapors will explode on contact with the air.



this is a good reason not to try this, there are safer ways to recover your gold


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## Bushka (Feb 27, 2013)

Geo said:


> Bushka, youtube is not the final say. do as you will but dont tell other members that have not studied the properties of hydrogen peroxide that heating and/or boiling peroxide is anything other than unsafe. do a wiki search or even a high school text book and gain some understanding. H2O2 is used as ROCKET FUEL. even though it is not combustible on its on, it will catalyze almost any type of metal. if you heated H2O2 and it concentrated to a certain percentage and there just happened to be a very small amount of left over metal in the container, BOOM, instant reaction. too, when H2O2 decomposes, what do you think it decomposes into? hydrogen and oxygen. two of the most explosive elements when combined.
> 
> youtube information should be considered inaccurate until it is confirmed here on the forum.especially if you want to use it on the forum as a "how to".




Geo - I was replying to butcher when I posted the video. He said you cannot concentrate peroxide by heating it, yet this guy seems to have concentrated it some, by how much we don't know. I made no comments regarding the safety of doing so (other than saying, as you did, that peroxide will combust spontaneously at high concentrations). I understand that peroxide can be nasty, but so is virtually every other chemical used in processing silver and gold. I'm sure I could kill myself with any one of them. How concentrated does peroxide have to be before it fumes and explodes? Can it fume if you are only letting it evaporate in a 100 "F environment at ANY concentration? My point is that if 30% peroxide suddenly were the only way to process silver, you'd bet there would be "safe" ways of concentrating it.

I'd be interested in finding the thread that discussed this before, but my luck on this forum of finding old discussions isn't so good.


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## Bushka (Feb 27, 2013)

Geo said:


> Bushka, youtube is not the final say.



Geo- I just reread my initial post above where I refer to the guy on youtube who is heating his peroxide. I do come across as advocating this method even though I didn't specifically endorse it. When I said I was going to concentrate some, my method was not to heat it, but to leave it to evaporate on its own and see it if was more active than 3% peroxide. My official stance on the matter is that people should listen to Geo (and maybe butcher) instead of some guy on youtube with fancy graphics.  

Long story short, I'm trying to minimize my nitric usage and peroxide seemed interesting. At 3%, the nitric solution becomes too dilute to manage so I wanted a cheap way to concentrate it.

Dan


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## Geo (Feb 27, 2013)

i really didnt mean to come off too harsh. please understand that this forum very often IS the final say about many things and people have learned to trust what they read here. a new member or even a guest from google may do a search for concentrating H2O2. if they find it here without being disputed, it can be taken as gospel truth. the last thing anyone here wants is someone being hurt or maimed or even killed following advice from the forum.

have you tried a hair care salon? they carry 33%. its used to bleach hair.


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## Bushka (Feb 28, 2013)

Geo said:


> have you tried a hair care salon? they carry 33%. its used to bleach hair.



Well now I'm not so sure what I'm doing. I am trying to process silver chloride that I converted to silver cement with lye and syrup. Because dried silver chloride is difficult to convert, I used a blender per GSP. What I think I have now is about 80 or 90% silver and the remainder unconverted silver chloride. So now I'm dissolving what I can in nitric, and then will collect and reprocess the silver chloride until I get it all converted to silver. I found that adding peroxide seemed to cause the nitric reaction to start back up, meaning that it started bubbling.

Having said that, I tried something that has me confused. I took about a 1/4 teaspoon of my silver cement and added about 25 ml of 3% peroxide. It began fizzing like crazy and did so for several hours. That was last night. This morning the fizzing had stopped so I added another 25 ml of peroxide. Again, it began fizzing strongly. The silver cement seems to be in very fine particles, but I cannot say that any of it has dissolved. I didn't weigh it since it was in water to begin with (neutral pH). Does silver catalyze the breakdown of peroxide??? There is no odor or color to the gas given off.

I sampled the water that my silver cement is in. The pH is near neutral, and when I add peroxide to it, nothing happens. It seems that the peroxide is reacting to the solid cement, and not the solution it is in. Any suggestions as to what is happening?

Dan


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## Bushka (Feb 28, 2013)

I should add that I checked the silver cement in peroxide after work today and found a whitish haze. This appears to be silver chloride. This morning I had added a few grains of salt but I didn't see any reaction at that time. I guess I had better search older topics on peroxide instead of reinventing the wheel. It would appear that peroxide can dissolve silver to some degree, but what does it become in a hydrogen peroxide solution???

Dan


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## butcher (Mar 1, 2013)

Water like hydrogen peroxide (water with an extra oxygen) can act as a reducer or oxidizer or a base or acid, with metals or other chemicals, depending on the metal or chemical, and with much depending on pH.

Hydrogen peroxide with acid can oxidize metals, hydrogen peroxide with sodium hydroxide can reduce metals, and much of this will also depend pretty much on pH.

The bubbling you see could be several things, depending on pH and concentration of reagents.

I cannot say what reaction if any is taking place.

But here are some thoughts I have on this subject.

If neutral solution and weak hydrogen peroxide you may just see oxygen escaping the mix with little or no reaction.

Stronger peroxide in neutral or slightly acidic solution could be oxidizing silver metal.

If acidic enough with nitric acid would not only assist the silver being oxidized and becoming a nitrate as the nitric acid was reduced to nitrate by the reaction, but the hydrogen peroxide (water and oxygen) would also help to convert free NO, NO2 (NOx gas) and HNO2 in solution back into nitric acid to dissolve a little more silver in the newly formed HNO3, also lowering the NOx gas that normally evolves from the reaction.

If the solution was caustic or a base with low enough pH the strong peroxide with the sodium hydroxide would convert silver chloride back to silver metal (very similar to the sodium hydroxide Karo syrup reaction).

I do not know the strength of hydrogen peroxide you are using, you also stated I believe this is almost neutral, but then speak of sodium hydroxide which is a very strong base, you also pretreated this with NaOH and Karo syrup and suspect only partial conversion, of silver metal and silver chloride, and I do not know how clean the silver was to begin with, so from all of this I cannot see where you are at, and you are beginning to get so many things coming into play it is starting to confuse me of what you may have now in the pot, or how all of the things are reacting with each other, (nitrates, chlorides, silver, organic compounds from cane sugar, sodium hydroxides, possible sodium nitrate, sodium chlorides, silver and possibly other base metals, with hydrogen peroxide thrown in on top) not much telling what reactions you are seeing if much of any.

I think if this was mine I would get it off the fence line and take it down one road or the other, acid road or base road, dissolve the elemental silver out of the silver chloride (or) try to reduce it all back to silver, (or) just reduce it as much as possible and melt it with flux like sodium carbonate and a carbon cover to try and complete conversion in the melt as much as possible, but right now you seem to be walking the fence line (adding more briars to the fence line as you go) not going anywhere if I understood what you described.

In the neutral solution hydrogen peroxide especially if dilute is probably only gassing of oxygen.
If stronger Hydrogen peroxide it could be oxidizing something like silver or one of the other compounds in the solution including one of the salts.

Actually am just getting confused of what your doing or where you are, or where you are going or wanting to go, but also I am just sitting here on the fence watching, not too sure what I am seeing also.

Hydrogen peroxide will not dissolve silver.
Hydrogen peroxide could oxidize silver.
With a base (NaOH) at HIGH PH hydrogen peroxide can reduce silver.
With acid at LOW pH (HNO3) hydrogen could help to oxidize silver as well as NOx gases.
Hydrogen peroxide can act as an oxidizer or a reducer (mostly depending on pH), for metals or chemicals in solution.

? just call me confused ?
Edited by the confused individual who say things backwards


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## Bushka (Mar 1, 2013)

butcher said:


> I do not know the strength of hydrogen peroxide you are using, you also stated I believe this is almost neutral, but then speak of sodium hydroxide which is a very strong base, you also pretreated this with NaOH and Karo syrup and suspect only partial conversion, of silver metal and silver chloride, and I do not know how clean the silver was to begin with, so from all of this I cannot see where you are at, and you are beginning to get so many things coming into play it is starting to confuse me of what you may have now in the pot, or how all of the things are reacting with each other, (nitrates, chlorides, silver, organic compounds from cane sugar, sodium hydroxides, possible sodium nitrate, sodium chlorides, silver and possibly other base metals, with hydrogen peroxide thrown in on top) not much telling what reactions you are seeing if much of any.



Thanks for your interest in helping me out, butcher. I was hoping you would see this post as I did find your mention of peroxide as an oxidizer of AgCl with caustic in another thread.

I had to laugh because you seemed to get more and more frustrated and confused as you typed on... By the end of it I think you looked like this: :shock: (just kidding)

Anyway, without going into all the details that I covered on a different thread, let me try to summarize briefly. Here's what I did:

1. I took very old AgCl and cleaned it up with water and then HCl, dissolving out what looked to be copper salts.
2. I rinsed and dried, and then in several batches I tried to convert AgCl to Ag in a blender per GSP. I used NaOH and syrup (as discussed in other thread).
3. I rinsed the final product in hot, hard tap water several times and left it under an inch of distilled water, which currently tests close to neutral pH (probably didn't wash enough with distilled to remove all dissolved species).
4. I took a small sample of the final product and confirmed that it contains silver, but also maybe 10 or 20% AgCl. I tested with ammonia to confirm AgCl still present.
5. I dissolved another small sample in 50% nitric and was left with a residue of AgCl (purplish).

Basically I stopped at number 5 because I do not yet have a good hotplate to assure thorough reaction with the nitric. In the meantime (while trying to find a cheap magnetic hot plate on ebay), I started looking for ways to minimize the use of nitric. I don't want to have to buy another $50 bottle, but see myself processing leftover AgCl again and again until it is all converted to Ag. So, I found the video on using hydrogen peroxide. It appeared that adding peroxide to my solution of nitric with some excess AgCl and Ag cement at the bottom seemed to reignite the reaction (evidenced by bubbles starting to percolate up). More recently, I added peroxide without any nitric to some of my silver powder and found the strong reaction producing lots of bubbles. I realized that the peroxide was probably not reigniting my nitric solution, but something else was happening. That's where you came in.  

So I'm pretty much just playing around with this stuff until I get a proper hotplate. I could just forget about the peroxide and just dissolve as much of my cement as I can. BUT, if the peroxide is doing something that might save me some nitric, then maybe I should run all of my cement through lots of peroxide (Oh, I'm just using 3% store bought peroxide) until it doesn't bubble anymore.

I took 1/2 tsp of cement and am mixing it with peroxide for the next day or so. I will then remeasure the volume of cement to see if any has disappeared. I know weighing is more accurate but for the moment this is what I've done.

I'll report back, and as usual any ideas are appreciated!


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## Bushka (Mar 1, 2013)

butcher said:


> With a base (NaOH) at low PH hydrogen peroxide can reduce silver.
> With acid at High pH (HNO3) hydrogen could help to oxidize silver as well as NOx gases.



I meant to mention that I don't think I've seen basic or alkaline solutions referred to as "low pH" and acidic solutions at high pH. Is this what you meant? Normally basic solutions (7 - 14) are high pH while acidic ones (0 - 7) are low pH.

Are you saying that in basic caustic solutions you can reduce silver oxide to silver, and in acidic solutions you can oxidize silver into AgO?

Thanks.


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## butcher (Mar 2, 2013)

Bushka,
Thanks you caught me, I did say that backwards, I have a bad habit of saying things backwards; I try hard not to do that on the forum.

Alkaline, Base, or caustic solution is High on the pH scale pH >7 to 14.
And acid is low on the scale pH <7 to 0.
pH being a scale of 0 to 14 with seven in the middle being neutral.

Silver chloride in a solution of NaOH (HIGH pH) also called a alkaline or a caustic solution, and strong hydrogen peroxide will reduce silver chloride to elemental silver powdered metal.
The silver gains electrons, sodium and the chloride forms a salt of sodium chloride dissolved in water, and oxygen evolves:
2AgCl + 2NaOH -->Ag2O + 2NaCl + H2O
Ag2O + H2O2 -->2Ag + O2 + H2O
Or
2AgCl + NaOH + H2O2 --> Ag + NaCl + O2 + H2O

Silver metal in a solution of nitric acid (LOW pH acidic solution), mixed with hydrogen peroxide the silver is oxidized to silver nitrate salts dissolved in solution, in this reaction the nitric acid is reduced to NO, NO2 (NOx) gas and a nitrate, the hydrogen peroxide actually reacts on oxidizing the NO, and NO2 gases than it does on the silver directly, the hydrogen peroxide basically breaks down to water and oxygen, the oxygen mixes with nitrogen oxide to form nitrogen dioxide, nitrogen dioxide mixes with water forming nitric acid, the nitric acid will now oxidize more of the silver,
2H2O2 --> 2H2O + O2
NO + O2 --> NO2
3NO2 + H2O --> 2HNO3 +NO

Oxidize (to lose electron)
Reduce (to gain electron)
for anything to be oxidized something else in solution has to be reduced, to say it another way for anything to lose an electron something else in solution has to gain that electron.

Silver metal (having all of its electrons) when mixed in a solution of nitric acid (a naturally oxidized acid, naturally missing electrons), the silver gives an electron to the nitric acid, in this reaction the silver metal is oxidized (lose of electron) and at the same time the nitric is reduced (gain electron) to nitrate, the nitric acid is also reduced to NOx gas.
Ag + 2HNO3 --> AgNO3 + NO2 + H2O
3Ag + 4HNO3 --> 3AgNO3 +NO + 2H2O


The (reduced) NOx gas is again oxidized (lose of electron) back to nitric acid by the hydrogen peroxide which is reduced (lose of electron) to water, which again forms the nitric acid from the gas, which would normally be lost from solution, leaving it to oxidize more silver.
As we showed above:
2H2O2 --> 2H2O + O2
NO + O2 --> NO2
3NO2 + H2O --> 2HNO3 +NO


Silver can be oxidized by strong hydrogen peroxide:
2Ag + 2H2O2 -->Ag2O + 2H2O

I assume with out acid the silver may just somewhat passivate and not go into solution coating the silver with an oxide layer, I am not sure here. Somewhat how I believe too concentrated of a nitric reacts with silver passivating the silver, by building a coating of silver oxide on the outside of the silver, slowing down the rate at which the silver would be dissolved into solution.


Silver oxides can form silver hydroxide in water the reaction is reversible:
Ag2O + H2O <--> 2AgOH

Bushka, 
Thanks for catching my mistake, it helps me try to say it right next time I open my big mouth,
I will correct my statement above, and I hope I did not say something backwards again here.


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## Bushka (Mar 3, 2013)

Looks good to me, butcher.

I decanted off the "spent" peroxide from my silver/silver chloride sample and measured how much precip I have left. It appears that some of it is dissolving. I added salt to the spent peroxide and it turned pinkish/white. I let this settle a day and then poured off most of the liquid to be left with a little pinkish precip. I added NaOH and syrup and it looks like it's converting to silver. Hard to tell with such a small sample, but it did turn dark and grey.

I took the precip I decanted and added more peroxide. It started fizzing like crazy again. So whatever is dissolving (silver, AgCl, or some unknown) seems not to have been exhausted yet. I'll be interested to see if this continues until all the silver is dissolved.

In any case I suppose this is just fooling around. I need to get a hotplate and start using the nitric. I think I might use the peroxide in some capacity along with the nitric to try and minimize the nitric consumption. Maybe use it carefully instead of diluting with water.

Dan


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## g_axelsson (Mar 11, 2013)

When I first started to read the thread I thought of manganese dioxide that works as a catalyst and splits hydrogen peroxide in water and oxygen, then I remembered something I read concerning hydrogen peroxide rocket so I made a quick search and found this.

http://science.howstuffworks.com/question159.htm



> Hydrogen peroxide's chemical formula is H2O2. When it comes into contact with silver, the silver acts as a catalyst. The reaction frees the extra oxygen atom to produce water, and also generates a lot of heat. The heat turns the water into steam, which the engine can eject at a very high speed through a rocket nozzle.



You need 90% peroxide to build a rocket, but that doesn't stop silver from working as a catalyst on weaker concentrations.
What you did was to turn hydrogen peroxide into water and oxygen, the silver didn't dissolve in the reaction. If you got a weak silver chloride cloud it is probably just pulled up by the bubbling gas.

Göran


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## Bushka (Mar 12, 2013)

g_axelsson said:


> When I first started to read the thread I thought of manganese dioxide that works as a catalyst and splits hydrogen peroxide in water and oxygen, then I remembered something I read concerning hydrogen peroxide rocket so I made a quick search and found this.
> 
> http://science.howstuffworks.com/question159.htm
> 
> ...



That's interesting. I wasn't far off, then. I thought maybe the silver was a catalyst. SOMETHING is happening, though what I'm not sure. I am definitely getting a precipitate when I add salt. It is presumably silver chloride, but also is pink. I added some lye and syrup to the pink precip and it turned grey, again assuming a conversion to silver. I'm talking a small amount, but it did generate silver in solution somehow. I don't know if the peroxide had anything to do with it or not.

Is it possible the original video of silver, nitric, peroxide and glycol didn't really react any differently than just nitric by itself, yet looked more volatile due to the peroxide reacting with the silver catalyst?


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## butcher (Mar 14, 2013)

The benefit of hydrogen peroxide with nitric acid is the oxygen in solution can oxidize the NO to NO2, the water in the hydrogen peroxide can dissolve NO2 back into it to form HNO3, so here gases that form and would normally escape can stay in solution better to dissolve a little bit more silver than nitric alone, and another benefit is less acid wasted as gases and less of those deadly red or clear fumes go out of your solution.


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## Bushka (Mar 15, 2013)

butcher said:


> The benefit of hydrogen peroxide with nitric acid is the oxygen in solution can oxidize the NO to NO2, the water in the hydrogen peroxide can dissolve NO2 back into it to form HNO3, so here gases that form and would normally escape can stay in solution better to dissolve a little bit more silver than nitric alone, and another benefit is less acid wasted as gases and less of those deadly red or clear fumes go out of your solution.



Yeah, I kind of realized that after I sent that last post. For someone trying to minimize every last drop of nitric, like me, the peroxide sounds like a good idea. I probably can't process as much at a time, but I'm only doing one batch anyhow.

Dan


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