AR Fume Safety/Prevention/Treatment

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toadiesop

Well-known member
Joined
Mar 28, 2007
Messages
156
The power of AR fumes as been on my mind for a while and something the new guy Scavenger said inspired me to make this thread.

We've all heard the stories that Scavenger just stated "Breathe fumes, die two weeks later"

AND IN NO WAY AM I DOWNPLAYING THE DANGERS WITH AR OR ANY OTHER CHEMICALS USED IN REFINING!!!

But, seriously, how much do you have to breathe before "the fear" sets in. I haven't used AR yet and when I do it will be outside, well ventilated, you know the drill.

I'm just wondering if these stories are a little exaggerated and if some of the pros could explain a little more on fume inhalation. I'm thinking accidents and what not. I mean

Now obviously you wouldn't want to stick your head right in the BFRC and breathe in like you would on the first day of spring, but if by chance you get a little wiff, how serious is it?

What should you do if it happens? And on what scale? How much would you have to inhale before you should take action (if you don't die on the spot?)

What are some symptoms that something is wrong? Nausea? Vomiting? Shakes? Blurry Vision? That whole death thing?

We all know the dangers and like I said, I'm not downplaying the seriousness of the fumes but I guess this "what to do IF" thread.

It's all well and good to display the dangers everywhere but I think we need more posts on what to do if an accident happens.

Take it away guys.
 
I should also state that information on batch size would be helpful too.

Obviously if your doing 5 pounds of material at a time in 5 gallon buckets you need a respirator and you need to be far, far away from any and all living creatures.

What about in the refining stage? Just a little bit of AR in pyrex dealing with 5 grams or so of mud, or foils, or karat scrap?

What are the fumes like on a small scale like that?

Is just being in an open area outside with a good wind and some common sense enough?
 
Toadie,

For starters here's a link to a short NO2 MSDS:

NO2 Short MSDS

and another to a long NO2 MSDS:

NO2 Long MSDS

and when using AR you'll have Chlorine gas also.

Remember that when you dissolve metals with AR or Nitric acid that 25-50% of the acid becomes this gas. Here's the post where GSP did the math for the Nitirc Acid required in the reaction:

Nitric Acid Reaction for 1 pound of copper

In a nutshell he states you need 1/2 gallon of 70% HNO3 to dissolve 1 pound of copper and in that reaction you should expect 50% of the acid (1/4 gallon) to become the deadly gas NO2 when used in concentrated form. He also states this is valid information for the AR reaction.

As you can see, the potential hazard is real when working with a single pound of scrap pins. Of course as the batches get smaller so does the cloud.

I've personnally processed a 10# batch of cpus and fingers using Poor Man's AR and the BFRC lasted no less than 3 hours. I did this outdoors and was very concerned for my pets and myself.

Catfish uses smaller batches of AR very frequently and can give us more information on these sized batches. GSP and Harold have obviously a vast amount of experience in this area and hopefully will fill in the blanks I have left. Many other members can provide stories of their experiences as well.

Steve
 
Thanks for the links Steve.

And a 3 hour BFRC??? Wow, sounds like a nightmare! :shock:

I've seen pictures of 5# of scrap in Poor Man's AR from a CD I bought on ebay last summer. That's how my minds eye sees the AR process. There was a large amounts of fumes.

I'll see if I can find that CD and maybe post a couple of pictures from it. It might even say who made it. no-reserve perhaps?
 
Copyright 2003, Noble Metals Recovery, Steve Spevak.

That's no_reserve correct?

He just posted here tonight too. That is if "Nobel Metals Recovery, LL" is him.


And my mistake. It was a 9# batch.
 
Toadie,

I have a copy of the cd also. No_reserve is Steve aka Noble Metals Recovery LL here on the forum. He's a really great guy and very willing to help. You should ask him to post some of his photos of the process. :wink:

Steve
 
Yes, I bought the CD from him too. When I did it, I never taught I would create a gold refining forum two years later ;)
 
HAHAHAHAAA!! That's how it goes Noxx. I can't believe I didn't beat you to it! :lol:

So Steve, any information on those fumes would be greatly appreciated.

And I'm sure more people can chime in on this question.

When you are dealing with 5 gallon bucket sized batches do you just stay away until it's done, or can you walk up and stir it without a respirator if you are upwind?
 
Toadie,

You missed my reply about fumes... scroll up and see. The fumes info is in the same posts as the story about the 10# of scrap.

Steve
 
No, I read it Steve. I guess I'm being a little to wordy. I'm like like sometimes :p my brain doesn't shut off and I just type my thoughts as quickly as they hit me.

I guess I'll do it like this.

1. When you have the BFRC how far away should you be without a respirator on and be safe to breathe normally? Do the fumes dissipate within a certain radius or are you still in harms way if you're, say 20 feet away.

2. Can you get up to the bucket using common sense? (wind direction, holding your breath, ect)

3. How do you know when it's safe?

4. How do you know when you're too close, or in trouble? The smells? Does your nose burn? Will you get light headed? I guess this is the main question I have. How do you know somethings wrong?

5. If that happens, what do you do?


I'm by no means a chemist, but I'm learning. 8)
 
I just discovered a terrific patent that could revolutionize this whole NO2 problem. I don't have it in front of me but I'll find the patent # tomorrow. Also, it would need some study and some math and lab work to make it usable.

It basically consists of adding definite quantities of strong H2O2 to any dissolving solution containing nitric acid. This would include nitric alone, AR, or NaNO3 + HCl. According to the patent, the H2O2 converts the NO that is produced back to HNO3 - in the solution itself! In this system, ZERO NO2 brown fumes are given off. The HNO3 is, therefore, twice as efficient and the presence of the H2O2 speeds up the reaction. Killer Patent! Three birds with one stone - No brown fumes - Acid will dissolve twice as much metal - Faster reaction.

To prevent the H2O2 from decomposing too rapidly, a small amount of ethylene glycol (antifreeze) is used as a preservative. The common 3% H2O2 won't work. Stronger stuff is needed.

There's a similar patent that uses sulfamic acid, I think, for the same purpose.

I've mentioned before that a guy I knew used H2O2 in a multi-stage NO2 scrubber. The H2O2 converted the NO2 to HNO3 in the 1st stage. The 2nd stage neutralized the HNO3 with NaOH. In Aflac's discussion of the machine he promotes, he said the scrubbers worked the same way, although he wouldn't say what the scrubber solutions were.

All of this goes hand in hand. That's why I was excited when I saw that patent.

I just found the Patent #'s. 3945865 and 3367874. There are probably more out there.

I just found these and haven't really studied them yet.

Steve, let me know what you think.
 
Toadie,

I really don't want to advocate bypassing proper safety procedures when working with deadly gases, but I don't want to leave you hanging on the answers so here's my stab at your questions:

[img::]http://www.goldrecovery.us/images/skullnbones_smallrev.jpg[/img]
1) The bulk of the cloud remains over the bucket in a cone shape that is big at the top and the size of the mouth of the bucket at the bottom. Of course the wind and temperature is going to influence this. The cloud will stay low to the ground when it's colder. The main concentration of the fumes is in the red portion, but not all of the fumes are visible.

2) I did the reaction outside on a average spring day. I held my breath the one time I got within 15 feet of the bucket when the cloud was present (to cover the bucket with an inverted plastic garbage can). I keep my face away from the bucket. I tried not to breath at all until I was at least 20 feet away. I wore gloves and tight goggles at all times.

3) I let the bucket sit for a full hour AFTER the cloud stopped. Even then I used extreme caution when approaching.

4) The first signs of exposure is a tickeling feeling in the nose or throat. The odor is bleachlike. If you breath any you will begin coughing, this is bad.

5) Read the MSDS for exposure treatments before you begin. Be prepared with these countermeasures on hand in the event of an emergency.

[img::]http://www.goldrecovery.us/images/skullnbones_smallrev.jpg[/img]

Again, I do not advise you to perform large scale reactions using AR without all the PROPER safety equipment (Respirator, Tight Goggles, and Chemical Gloves). Even if you are safe, your neighbors and pets may not be!

Stay safe Toadie,

Steve


P.S. This is my 1000th Post !!!!!! :p
 
GSP, this patent is VERY interesting. I will read it.

Steve, I congrats for your 1000th post. Just look under your name ;)
 
GSP,

I seem to remember seeing these patents late one night while googling. I had forgotten all about them until you mentioned them. I've only read the abstracts and will need time to study them.

If this pans out then it will make life a lot better and safer for the AR crowd.

Great post as usual GSP!

Steve
 
Thanks guys!

And Steve, I guess my motives for this thread were twofold.

For myself I wanted to know what it would be like in small batches. I don't think I'll ever be comfortable doing HUGE batches of AR and I don't see a time I'll ever need to. AP works just fine! I was thinking about when I have an ounce or so of buttons saved up and I want to hit 3 nines. Just a little bit of AR in a measuring cup.

Like you said, no all fumes are visible and that was one of my concerns.


The other reason I asked is because, while I know about staying safe and asking questions many of the other new people might not. It's good to know layman's specifics sometimes like "Stay 20 feet away" "Wait an hour after the fumes die down" ect.

And also how to tell that something in wrong and what to do.

Thanks everyone!
 
Harold said:
goldsilverpro wrote:
FUME HOOD! FUME HOOD! FUME HOOD! FUME HOOD!


Where have I heard that before?

I know, I know, I know... I'm working more on that problem this weekend. After the garage is completely reorganized, I'll layout some plans and share them with everyone.

All,

As the pros have so graciously pointed out time and time again, there is NO SUBSTITUTE for a good fume hood where safety is concerned when dealing with toxic gases. I whole heartedly agree with them and would recommend that everyone here work towards building one. My previous post about 'backyard AR' was a very scary experience to say the least. I was very lucky to come thru it safely. As I stated in that post, just because you take all the safety precautions for yourself, it DOESN'T mean those around you will be safe.

My new mantra until mine is completed:

FUME HOOD! FUME HOOD! FUME HOOD! FUME HOOD! 8)

Be safe and take care,


Steve
 
:idea: This works great for 14 pound pentium chip batches...
using a 3/4 gallon poor or rich man's 'recipe'.

Using the lid from the 5 gallon drywall bucket, REMOVE RUBBER GASKET from inside the lid's edge, drill or carve hole for PVC pipe with elbows, to allow the pipe to angle downward into a plastic 24" deep bin 3/4 way full of water and wood ash mix, just gotta mix it up so it's like a THIN milkshake consistency since the fumes will come out of the pipe at pressure, you want the bubbles to travel freely from the end of that pipe, not clog like will happen as the ash settles, LOL, but anyways, you get the picture... You could try something liquid like premixed water and drano. Either way, an alkaline solution with the pipe near the bottom cuts the fumes down about 95%. Cover the bin with a wet towel and sprinkle the ash on top of that, might need some clamps to hold the towel in place. This traps/neutralizes the fumes that escape the alkaline liquid part. As with all reactions, when the bin bubbling stops, the reaction is nearing the end. Take the pipe out soon, as the reaction cools, it will suck up the water through the pipe and a possible nasty surprise could ensue. You'll notice that some fumes will stay in the bucket, as you remove the lid, hold your breath. The liquid on the underside of the lid is highly corrosive and should be rinsed into that bin. I use a quart or so of rain water. You'll also want to rinse down the inside of the bucket as the condensed liquid is highly corrosive.

There are some other methods that are FREE and work great too, I'll post them later. I think small batches are for the birds! LOL It is safe to say that I do this all without gloves or respirators.

some conditions affecting fumes: Humidity, wind direction/speed, air temp, etc... all true. If humid, use the neutralizer. If dry air and windy, just let it rip, using the lid with a vent hole a good 1000 feet from neighbors, wildlife, etc. Make sure the hole in lid is clear first though. You can also cover that with a cloth/ash to minimize the escape. As long as you don't seal the vent shut, you'll be OK. I've even trapped the fumes, cooled them into liquid then used them to dissolve more gold plated stuff. Either way, fumes are nasty, stay upwind and try to minimize them if possible. The garbage can upside down seems a bit archaic, but, to each their own, :lol:

AF 8)
 

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