Concentrate Nitric Acid ?

[Noxx]

I believe that
calcium sulfate is pretty much insoluble.

In fact, thats the real problem...

 

[Irons]

I was thinking of thiourea with the CLS.
Has anyone else tried using CLS from action mining,
or tried leaching with electro-precipitation?
The CLS manual also shows a zinc precipitation unit,
and ion exchange resins that look interesting.
And in his dvd he shows an activated carbon filter
that traps the metals, I was thinking if you would be
able to make something like that from a pool filter?

Thiourea is very toxic. Don't even think of using it.

http://www.scorecard.org/chemical-profiles/html/thiourea.html

HEALTH EFFECTS

Probable routes of human exposure to thiourea are inhalation, ingestion, and dermal contact.

Non-Cancer: Skin sensitivity in the form of eruptions may occur from repeated contact with thiourea. Thiourea may cause toxic effects on the blood system including bone marrow toxicity and reduction in red blood cells, white blood cells, and platelets. Enlargement of the thyroid (goiter) and spleen has also been reported from exposure to thiourea (HSDB, 1995; Sittig, 1991). The United States Environmental Protection Agency (U.S. EPA) has not established a Reference Concentration (RfC) or an oral Reference Dose (RfD) for thiourea (U.S. EPA, 1995a).

Cancer: There is evidence from studies in experimental animals that thiourea causes liver and thyroid tumors. The U.S. EPA has classified thiourea in Group B2: Probable human carcinogen (U.S. EPA, 1995a). The International Agency for Research on Cancer has classified thiourea in Group 2B: Possibly carcinogenic to humans, based upon sufficient evidence in animals and inadequate data in humans (IARC, 1987a).

The State of California has determined under Proposition 65 that thiourea is a carcinogen (CCR, 1996). The inhalation potency factor that has been used as a basis for regulatory action in California is 2.1 x 10-5 (microgram per cubic meter)-1 (OEHHA, 1994). In other words, the potential excess cancer risk for a person exposed over a lifetime to 1 microgram per cubic meter of thiourea is estimated to be no greater than 21 in 1 million. The oral potency factor that has been used as a basis for regulatory action in California is 7.2 x 10-2 (milligram per kilogram per day)-1 (OEHHA, 1994).

 

[Anonymous]

I must be missing something. If calcium sulfate drops out wouldn't that leave you with nitric solution? That you could just decant off?

 

[lazersteve]

I must be missing something. If calcium sulfate drops out wouldn't that leave you with nitric solution? That you could just decant off?

What Noxx is referring to is the fact that the calcium sulfate formed literally absorbs all the liquid along with the bulk of the nitric acid (what doesn't get absorbed goes up in smoke).

If you dissolve the calcium nitrate (as with the cold sodium nitrate method) in a minimal amount of water you end up with a thick pudding of calcium sulfate and nitric acid as soon as you add in the small amount of sulfuric acid. For this reason you would need to distill the resulting pudding to get your nitric out. It works, just not at low temperatures and without distillation like the sodium nitrate method does.

The pudding forms so quickly you will get a plume of nitric acid vapors coming from the reaction as the sulfuric acid is added.

The resulting mush is very toxic and hard to work with. This method is best done in a glass still in a lab environment.

You could add excessive amounts of water to capture the nitric in the cold, but you end up with weaker nitric, instead of stronger like with the cold sodium nitrate method, and you'll need to filter or distill the calcium sulfate pudding to get all the nitric acid out.

If you are looking for quick, easy, strong, nitric acid just follow my 'in the cold' recipe given here:

No Distillation Nitric Acid

Steve

 

[Anonymous]

I see now, I knew that I was missing something and what you say makes perfect sense. thanks.

Jim

 

[Palladium]

Replay
:wink:

 

[viacin]

I found this, and thought I would see what you guy thought. This seemed like a good place to put it, with all the other nitric processes. Obviously it is played down for people who don't know what they are doing. The only difference is the amount of chemicals this guy uses. According to him you could make a gallon of nitric with 1lb of sodium nitrate, 1.8L of water, and a gal of sulfuric acid. Now that's cheap.

" You can make 2 batches of Aqua Regia or about 1 gallon of nitric acid with one lb of sodium nitrate. Here is the formula for making nitric acid. Pre dissolve 1/2 cup of sodium nitrate in 16 ounces of hot disstilled water and mix this with 1 quart of sulfuric acid. " he doesn't give many more details, but it pretty much follows steves cold process.

Will this work, or will I end up with a solid gel like I read about in another post. And what would the concentration be? I tried doing the math myself, but I still have questions.

( ? / (?+473) x 100 = percentage

I know that :
? = the mole of nitric acid (63) x the amount of moles in the solution
and 473 is the 16oz's of water in grams.
But how in the world do you figure out how many moles you have in your solution in the first place?

gah...I need a book. Can we include this math in the book Lou has purposed? lol.

 

[Noxx]

Viacin, go see my reply in your last thread.

You would end up with a solid block if you use very little water and cool down your solution. All the salts will crystallize and will form a block.

 

[butcher]

Viacin read this forum over good,also check other info on the computer, it takes time and patients, but all the answers are easily available, and you will be spending more time processing gold. most all questions have been answered on this site, or are easily found searching and reading, of coarse this allways brings up more Questions, to search answers for, also read Hokes book, soon you will be answering your questions before you can think of them, isnt this fun?

 

[butcher]

In my opinion distillation would be only way to make pure nitric at high concentration easily, I have spent many hours studying nitric, can easily be distilled safely, with or without lab ware, if the solution you are distilling from has a high concentration, you will at first distill of just about pure NO2 very little water, the NO2 level in the solution will continue to drop until the boiling solution reaches azeotrope 68%, (can change receivers here), then you will boil off 68% nitric till a salt left.


But if you are starting with a week nitrate solution you would boil off mostly water and very little NO2 until the boiling solution reached 68% concentration then it will boil off at 68% till dry salt left.

So if you want concentrated Nitric acid without distilling you make it in proper mole ratios such as the formula Steve and others have worked so hard to perfect and studied on, or can use a weaker formula and evaporate off mostly water till 68%, but even freezing to remove salt there will still be a little left, most processes this is not a problem and can be beneficial to some. Usually I see distilling only necessary for purer acid or as part of a refining process that I am using.
you can check my other post on some simple equiptment I have used safely to distill, also using distilling to process a batch not releasing the Dreaded deadly brown fumes but captureing them for later use.

 

[viacin]

Gah, I double posted. sorry guys. I meant to come back to this one and edit out the question after I posted it in the other topic. Sorry about that, I forgot.

And yes butcher, it does seem that the best (and possibly only) way to make pure nitric acid is to distill. I'm really picky about my chemicals, so I will probably end up distilling in the long run. But the cold method is easy, quick, safe, and cheap from an equiptment point of view, so I really prefer it right now. I was liking this guys formula though because it makes more nitirc with less chemicals. But common sense says that it must be less concentrated then.

When it comes time to make my first batch, which should be this weekend btw, I'm gonna follow Steve's cold method. Later on as I learn more I will try some of the other methods listed here.

 

[butcher]

I would not use distilled nitric if I was starting out, I wouldnt use a nitrate at all, I think you will have more sucsess with HCl peroxide, and Hcl and household bleach methods, unless you are refining high Karat gold ect. the nitrate can be a challenge and hard to drop gold from (wish I had all the gold that was lost from people who disolved it in Aqua Regia and couldnt precipitate it, because of the nitrates) Yes Viacin I can see you will do very well in this field or any other you put your mind to, but you dont need a sledge hammer when a tack hammer will do, and sometimes , well most times good enough is better than perfection,Unless you are in the final stages of pureifying your gold then read up on all of Harolds posts, then you can to get your perfection, but that takes more (time) and expierence, and patients,some wisdom TIME (funny seems to also be associated with age If God gave it to us when we were young we would have waisted it like we did with every else :lol: ) you are a quick study and will soon be sucsessful.

 

[butcher]

I seen where you said poormans nitrates are safe, I dont consider them safe, just relatively safe if handled properly, with all the understanding of the DANGERS involved, before making or using them or any of this information on this forum, or anything i read from a book or got off the intranet ect, I would make sure that I knew the dangers involved to my health, the safety of myself and others, a simple mistake with these chemicals can be deadly, metals and nitrates can form explosive mixtures,nitrates and oils ect very dangerous Do your homework first. not to scare you just friendly reminder

 

[viacin]

Actually I'm going to disolve my extremly impure gold scrap, if it's even gold at all. Call this a test run for a new sample of scrap I have aquired. It's at least 87% base metals, and only about 12% gold. I'm not actually running AR, just a good nitric soak to see what is left. My guess is nothing, but if I'm lucky I'll put in 10g of scrap and get 1g of gold, and other PMG's of course. I decided to go with a nitric soak based on advice from noxx, harold, and husker. Plus hoke states that if you have very impure gold then the nitric bath should be your first step. She even says that it will give me almost pure gold if the scrap is extremly impure to begin with.

From what I understand of this, there will be no precip needed, as nitric alone will not disolve gold(?).

As for saftey, all of my apparel arrived today. I tried it all on and managed to scare the pesky kids in my backyard pretty nicely. I did make one goof up though, I ordered a SM respirator instead of a LG. It still feels like it seals well, but it does not fit on my face where it is supposed it.

Speaking of which, how noticible is a large quanity of NO2 fumes (assume 10g of gold powder and enough nitric acid to cover them)? My very impure scrap should make a very large quanity of smoke. I live in the country (outside city limits) on a cul-de-sac in a subdivision, and I have a decent sized yard (1/2 acre) with a privacy fence up one side. I don't know all the laws, but I'm pretty sure you shouldn't do this in your back yard, or off of balcony of a apartment in the city. The other side is open to two different neighbors. They are going to suspect something when they see me in my full chemical set up, and I don't think they will think too kindly of what I'm doing. Especially if the wind starts drifting. Maybe I should do it at night, or fire up the smoker grill first. Any suggestions?

 

[qst42know]

Control your fumes at the source. Just forget my use of the jar, it was a bad idea from the start. I run a marble condenser on all nitric or AR reactions. The less my neighbors pay attension the better.

http://goldrefiningforum.com/phpBB3/viewtopic.php?t=3269&start=0&postdays=0&postorder=asc&highlight=genie

That full chemical gear is going to attract a lot of scrutiny from your neighbors. They're going to wonder if they need the same suits. And they will research the local ordinances for you.

 

[viacin]

The less my neighbors pay attention the better.

That full chemical gear is going to attract a lot of scrutiny from your neighbors. They're going to wonder if they need the same suits. And they will research the local ordinances for you.

My greatest fears exactly. ty for the link.

 

[qst42know]

Two sections of privacy fence hinged together may be enough to deter prying eyes. Hoke recommended a window fan and I use one on days the wind is not cooperating. If the fumes are drawn through the fan consider it dedicated, contaminated, and don't use it for anything else.

If your neighbors ask what the suit is for do your best to convince them it's your Halloween costume. :wink:

 

[viacin]

ha ha yes, halloween....thats the ticket. I have about 220 feet to fence on one side, and believe me, I'm looking into it. The $3,000 price tag (if I do all the work myself) is prohibitive right now. Maybe after I run a couple of batches

 

[butcher]

I would use acid peroxide to remove the bulk of copper ectera slower and no brown fumes, also cheaper.

with alot of copper takes alot of nitric, creating alot of fumes, even if a plastic trash can over it and you were using fan ect.

your neighbors will probably get that cloud floating through their yard those lil kids you scared may be having a bbq with granny who peaks over the fence seeing you dressed like someone dealing with something somthing the Goverment is looking for.

call the firedept, DEQ,EPA FBI ect.

youll be looking for a black hole to crawl into :!:

but seriosly try a little batch of HNO3 and copper first so you Know what to expect. and this reaction can get hot enough to break glass , also if you are just starting out and have just a small amount suggest do it in small batches expierimenting the different processes, and not loosing your gold.

Hoke, Harold ect I am sure would eliminate most all the base metals (copper) they could,using the safest and cheapest way first.

then incenerateing to remove chlorides and trash and then useing nitric on the base metals left ( you are not working high karat material, and not in final stages of refining) no need for nitric untill you get to that point and you will be cleaning your gold and re refining it, this is were they are suggesting nitric to eliminate base metals,
( then the nitric can be used and a heck of a smaller brown cloud) and you will have your gold not losing it , :wink: you and your neibors will be happier and healthyer

 

[butcher]

Any black holes in yer cul- de sack :?:

Can you explain making nitric to the authoritys :!:

just kidding with you here, but do consider my advice I am trying to be helpful