Situations to Avoid--The Safety Thread

[Geo]

i had a nitric acid burn a few months ago that nearly took the nail off. i didnt even realize i had gotten it on my finger. i picked up a watch glass without gloves on and the condensation ran under and around the nail. i though it was just water and thought no more about it until that evening when it felt as though something had been stuck under the nail to the quick. by then it was too late to neutralize and by the next day, the entire end of my finger was yellow. its healed now with no side effects but im aware of that particular danger now.

 

[rickbb]

Check your safety gear often and before use.

Sitting here with a nice blister on the end of my left ring finger due to an un-noticed hole in my "good" gloves.

 

[Fabiank94]

Even tho this is a obvious think never drink alcohol or do drugs before or meanwhile preparing for your refining.
Allways be suspicious of strange smells it can be some leaking gas or anything else.

Things to have/do
Have a working area with a good ventilation system.
Working clothes, Gloves, Glasses, leathercoat/coat, Respiratory Protection (face mask), phone nearby.
Labels to keep it all strutctured. (Remember to put the stuff back so you dont forget some acids that should not be mixed together at the same spot keep the seperated.
Fire alarm at the working area + Phone.
Never have something flamable like pillows etc in the working area.
Never eat nor drink at the working area.


Worst case scenario plan, ex eyewash, shower, foam fire extinguisher (if any fluid is on fire), a phone nearby with alarmcentrals phone number.

That some stuff i came up with. I hope it helps

Yours Sincerly Fabian

 

[rickbb]

I just went through a major ice storm, knocked out the power for 3 days.

I had a batch of AP and a HCL soak of some boards under the fume hood at the time.

It was about 6 hours before I could get to the shop and set those containers outside some place safe.

Needless to say everything made of steel/iron in the shop had a light layer of rust on it. And everything else has that greasy grime feel to it from the deposit of the fumes.

Moral of the story, have a backup plan for when, (not IF), you lose power to your fume hood.

 

[Digitaria]

Thanks for this - defo a few things here which I will employ. Newby signing off on this module.

 

[Martijn]

Regarding safety of other people, Im sure nobody would advocate refining in an apartment. And some houses these days seem very close together. My question is how much room would you need to do your refining without harming people next door? An acre? Five acres? I live in a house on five acres, (330 feetX660 feet). My house/garage/workshop is centrally located on the property. Is this enough room to safely refine small batches outside without the fumes/smoke getting to the neighbors? Would I have to shut down on windy days?

A bit late to react, but better late than never. The more wind, the more the produced gases get diluted in air and dispersed faster. So a soft breeze to no wind I would say is more dangerous. In these conditions the wind direction may also suddenly change, blowing towards you instead of away. And in low wind, gases can accumulate better to dangerous levels, slowly passing over a couple of propeties and maybe staying closer to the ground if heavier than air.

But if you have a runaway reaction (always consider the worst case scenario) could it produce a dense enough cloud to pose a danger to your neighbors or kids playing next door in the garden? You would have to know the estimated values produced, with wind dispersion models and compare to the maximum acceptable 'safe' level. It's quite a science, determining all the variables.
Considering the risks described on some of the MSDS's I would go for a more safe option to at least use some kind of condenser scrubber vessel and run the fumes trough an absorbing solution.

be safe.

P.S. I'm thinking of categorizing risks and possible control measures for my setup for the different processes for silver refining and gold de-plating and refining, I will share it when it's completed or when I need additional input from y'all.

I am going through the safety threads to pick your brains already. I really love this forum!!

 

[Oak]

Well, thank you so much for this valuable safety information.
As a refining noob, information is power.
I am very glad I started my search for information in a forum such as this one.

 

[FrugalRefiner]

Oak,

Welcome to the forum!

You've made a great choice by starting in the Safety forum. From here, I'd like to suggest the Tips for Navigating and Posting on the Forum thread.

Dave

 

[rickbb]

Small mishap the other day, kept small due to having a spill tub in place.

Had a 1L beaker of HCL on the hot plate warming it up to wash some precipitate and noticed a white ring of some kind of salt forming around the bottom of the beaker where it sits on the hot plate.

I don't remember any spillage or liquid running down the outside to hit the hot plate to create that kind of thing. So I turn the heat off, wait for it cool down, and then pickup the beaker to see what's going on.

Slosh, the beaker was cracked all the way around the bottom edge and when I picked it up the bottom stayed put so all I lifted up was the outside, now a hollow glass tube.

All the hot HCL and the mud was now running down the hot plate and into my spill tub that I do all my stuff in. It's sized to fit the entire bottom of my fume hood just for that purpose.

Didn't get hot acid anywhere and saved all the mud. Was a mess to clean up, but no hazard or damage due to having that plastic tub to catch everything in.

Always think about spill management, it's not if, but when.

 

[Smack]

I'll have to remember that one rick.

It's been about a week ago now, working in the lab for the day, everything was fine at first. Went to eat and got right back to it but made 3 simple minded bone head mistakes (procedurally speaking) and was so upset with myself I just packed it in and went home for the day. Didn't lose anything but could have and it made for more work getting everything back to where it should have been in the first place. Don't know why I lost focus....I don't remember any eye candy from when I went to eat.

 

[IR0NHE4D]

Wow, guys!! Lots of great information and ideas! I'm extremely new to this hobby/activity, and safety is my primary concern.

1) Has anyone tried creating a safety shield/working environment tailored to this activity? This sounds like a silly question, but my brain immediately went to a work area similar to the setup of a small-scale sand blaster. PPE is basically built into the chamber. Gloves, splash guard, etc. would be part of the setup. Probably wouldn't be too hard to include the fume hood and the spill containment bin. I was just thinking that one of those web cameras could be built into it as well, so you could look at whatever you needed (and as closely as needed) without the fear of losing sight, or more importantly, life.

2) Having worked with some HAZMAT in previous jobs, I will definitely be labeling everything that I utilize as a storage container. I might even label each container I use in the process, i.e. sharpie on beakers and other containers. On this same line, I normally had the processes written out in a chart format. That way I could always see where I am in the process, and what chems were being utilized...just in case I brain farted.

3) Is there a color chart? I don't like guess-work. When looking at chemical reactions, I like to have as much reference I can, so I know what is going on. Having easy references for before, during, and after a reaction, is a great reference. Might even be more important for a new guy like myself. If one doesn't exist, I'll keep y'all posted.

4) Eye-wash/shower station idea. I'm thinking about setting up 2 5-gallon buckets filled with water as my emergency rinse station. I'm picturing an industrial eye-wash station where you pull the caps off and the water just comes jetting out. I'm not sure how it will work, but I'm thinking it would be great to put a shower head, or two, with a chain and valve. Same deal. Pull the chain and "water-on".

5) Blower filtration. I guess this could have been part of the enclosure bullet, but would it be advisable to route the exhaust gases through some sort of bubbler to keep from just venting the gases? I was thinking that you could cap the reaction vessel and pipe the gas too a second container of neutral solution (water, or water + baking soda), to neutralize the gas. I would imagine that the same could be done with some sort of exhaust fan. Fans could be powered by DC, so a battery backup could be included.

I hope I didn't sound antagonistic in this post. It was just what popped through my brain. I loved the other suggestions and safety precautions I read already!!! Like I said, y'all are incredible for putting this type of forum together!

Any inputs are greatly appreciated.

Be safe!

 

[butcher]

IR0NHE4D,

Good thinking, keep it up.
Great work by starting with the safety threads, I think you will do well in this field.

Yes there has been discussion of using an enclosed (gloved environment) similar to what you are referring to (no mention of camera that I remember), for some things it may work, although a fume hood is probably more useful (my opinion only).

Labeling and note taking are very important.
Keep a hazmat folder of your chemicals for reference, it can also be helpful and a good tool to have when the authorities knock your door down to see what you have been cooking up in your lab.

Color charts, some reactions we can have color charts as guides, pH and testing solutions, some reactions and precipitation, so using color as a guide in some ways is a helpful tool, then again we cannot always go by or trust colors, example take gold in solution a yellow color, well iron can also give a yellow color, take copper in solution a blue or green color, well iron can also give a green color.

Colors of solutions or other things can be very helpful in some ways, they are not always the best way to determine what a reaction contains, using colors alone you can easily be fooled, especially with so many different possible reactions, or conditions in some of the solutions we work with.
As you get further in your study you will gather a lot of information of colors and where they can be helpful...

You will find many references to colors, and charts on the forum, you will also find where many are fooled by colors...

Eye wash, is a good tool to have handy, ( a must have in my opinion), I use a water hose with a valve on the end. Were I can quickly get at it while blinded. I also keep a wash bottle handy for that dedicated purpose, and keep a bottle of eye wash saline handy... There are other things it is good idea to keep handy like a box baking soda for neutralizing acids (or other bases)...

Capturing the gases, scrubbing them,or distilling them for reuse are also important for safety, and can be useful tools, not everything you generate is waste, it can also generate very useful byproducts...

Welcome to the forum

 

[Topher_osAUrus]

Firstly, welcome to the forum ironhead. Butcher has given you great advice so far. And, by starting off in the safety section, you have undoubtedly earned a "kudos" from a great many of the long time members!

I will try to add a little bit (what i can)

1) fume hood is what you are looking for. There are excellent designs posted by a few great members -4metals, kurtak, phil, and others. Im sure adding a camera would be easy to do, should you be apt with building things.

2)yes, yes yes..label it all! Do as butcher suggested, print out every MSDS sheet for every chemical in your lab, put it in a bindwr that is easily accessible.

3)while there is no color chart, there is a great book that will give you a great abundance of information, rivaled only by this forums collective of info. Hoke - refining precious metals AND Hoke - testing precious metals. Both are held by everyone on this forum as the bible of refining. They are a great read (if you are a nerd like most of us, then itll be a real page Turner..if you aren't, then it may be a drag, but if you are in serious pursuit of this fiels, it is an absolute must read...it will help you get acquainted with the metals in solution, their color, procedures, etc... Its invaluable)

4)pretty solid idea.. I have an "oh no!"-station, that has a few gallon jugs of water.. A few boxes of baking soda... VERY dilute NaOH water, and VERY dilute HCl, as well as a little vinegar, bandaids, etc... Just stuff you hope to never need to use, but should have just in case..

5)Harold suggests having a filter in line on the fume hood to easily recover volatile losses that just went up in smoke or steam..he did refine commercially, but, his recovery from the filters bianually, was/is beyond impressive. Most fume hoods scrub the gasses before venting to atmosphere, and i believe they use sodium hydroxide for the most part, not sure how well baking soda would do if you are running processes in great volume.

Best of luck on this new found field of study for you.
Hope this may help

-topher, the-tickled-pink!

 

[IR0NHE4D]

Many thanks to Topher and Butcher for the responses and the advice!

After posting my comments, I did more research and eventually found the fume hood posts! Doh! I felt pretty stupid for re-asking the question. Great source of information, though. I did see a "hood", created from a storage tub. Had glove holes, and everything. Pretty cool idea. I may start with a variation of this.

I have been reading in the Hoke book "Refining Precious Metal Wastes". Invaluable resource! My plan, is to walk through the book. I plan to do the testing activities and LEARN. The storage/hood should suffice for those "labs" listed for learning. I will have to look for the other book, "Testing Precious Metals". So far, I'm almost riveted.

Great suggestion about the MSDS sheets. I had planned that for sure. Labeling is a must. You just cannot be too careful around these chems. There are some parts of life that you only get one shot, and I would hate to have a hobby do me in! Besides, I think my wife would be pissed if they only maimed me. haha!

I definitely agree that the color chart is not the end all reference. I just like to be familiar with the expected outcome, and any indications of success or failure are helpful.

I'm planning to start very slowly/small. Experiment and learn in a mostly controlled exercise. Then, I can scale up and enjoy myself. For the start, I will probably just be sure I'm outside, and provide some ventilation for more safety. I'll definitely be digging more into a scrubber setup before I get much more serious. I've seen a few examples that look pretty good, and moderately simple to build.

I will likely just focus on Gold, Silver, Platinum, and Palladium. I'm guessing these are the big 4, but they are definitely easily found in similar equipment.
I have found that there is a LOT of information in this forum, so I will continue digging.

Thanks again for all the help, comments, and the resources!!!

P.S.: After the Hoke book(s), I'll probably be getting the information from Lazersteve's site as well.

 

[Topher_osAUrus]

Thats excellent to hear (read)!

For the scrubber, here are a few threads to get you going.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=9115&hilit=fume+scrubber

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=40&t=23159

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=40&t=19965&start=30

Once you have your AB-train / scrubber, there are a great many things you can do with it. Save your lungs, save the NOx gasses from nitric/AR reactions and make MORE nitric acid, and distill your homemade nitric, etc...

Miss Hoke's book -testing precious metals- is here on the forum
http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=54&t=16555

If you cant get evac flasks for cheap (for the scrubber), some guys use pvc tubing.

If you can't get around to building one before your acquaintance experiments, using a watch glass will reflux the NOx gas pretty well.

Diluting the acid also helps to keep the red cloud at bay, but, at the expense of time...you will get more mileage per ml, but it will take you longer to complete your dissolution.

When you have your stock pot started. Try to keep a couple solutions separate from one another. Like AR thats had gold precipitated, and nitric that has been used to dissolve silver (which you then cemented on copper).. That way, when you want to recycle or reuse the nitric, you have chloride free nitric, which will keep silver chloride out of your reaction (Hoke tends to treat silver chloride like its a nuisance...but, back in 1940, it wasnt worth much compared to now...and...silver chloride IS a nuisance..)

(I jist learned this from Lou, but) keep any solutions that had nickel in it away from sulfamic acid (which is used to expediently remove nitric from ar) as sulfamic is a chelator.

There are other things that I wanted to add, but, they are slipping my mind right now, and this reply is already ridiculously long. So, I will leave it at that!

-topher, the talkative

Edit to add: goldsilverpro's book, while i haven't purchased it yet, I have yet to read anything but excellent reviews from members here. They all say its great.

C.W. Ammen's book "recovery and refining of precious metals"

There are a lot more books out there, a section in the forum here has suggestions from other members.

I myself have downloaded quite a few, if you want me to send you the pdf's I have I will gladly do so.

Im still waiting for Harold to write a book...he CLAIMS that nobody would want to read it, and it would just be a rewrite of hoke... But, I know he has much to add... Like anecdotes.. 20 years a commercial refiner, I'm sure theres a great deal of stories he hasn't posted on the forum...
(he DOES however have a pdf called "Harold_V refining karat gold" that I found online, which apparently was for a customer of his[if i recall correctly...a friend told me about it]..)

Id like to read a book by Butcher as well- he is very technical in his posts, and I love it

4metals and Lou as well, they are amazing with chemistry.
As is LazerSteve
Kurtak probably has enough experiences in his refining experience to fill a couple books

(they don't have books, but, click on their name...search their.posts...read them all)

Some of the best bits of this forum, are when our resident professionals are talking to one another in a thread... Its great.
I have multiple folders on my phone/laptop dedicated to such..also have about 6 notebooks full, and always keep a notebook or two on me... Always...

The wife hates it, but, pshh..what does she know
:mrgreen:

-topher, the thrice-over-talkative

 

[upcyclist]

A great start!

I definitely agree that the color chart is not the end all reference. I just like to be familiar with the expected outcome, and any indications of success or failure are helpful.

Try Lazersteve's General Reaction List!

I will likely just focus on Gold, Silver, Platinum, and Palladium. I'm guessing these are the big 4, but they are definitely easily found in similar equipment.

Since this IS a safety thread, I'll point out that platinum salts, and salts of other platinum group metals (PGMs), can be extremely toxic. There are refiners on this board that are perfectly comfortable with cyanide processing and still won't mess with PGM salts. Personally, I'm recovering PGMs and will send them on to someone else for refining.

 

[Anonymous]

Since this IS a safety thread, I'll point out that platinum salts, and salts of other platinum group metals (PGMs), can be extremely toxic. There are refiners on this board that are perfectly comfortable with cyanide processing and still won't mess with PGM salts. Personally, I'm recovering PGMs and will send them on to someone else for refining.

I'd be one of those- as is Nickvc, and you are quite correct there are plenty of others too. The quandary is that there is an unreasoned fear of cyanide processing, whilst many people seem perfectly happy to take the bigger (albeit longer term) risk with PGM salts. There's a logical argument that could be reasoned that exposure to some of these salts, even in low quantities is far more dangerous than cyanide processing. That's a debate I would welcome with input from those far more experienced than me to make the salient points.

 

[Lou]

I'm glad to see there's more awareness of so called tetravelent or chloroplatinate allergy. This has been the trend in industry. I have worked diligently to minimize as much as possible those risks in my handling of them by physical and chemical methods. Tetravalent platinum is a necessary evil in its hydro metallurgical process (except, for instance, plating with cyanide) are a necessary evil when refining the metal.

Here are some examples of control techniques/practices:
1. Dedicated handling areas (i.e. a labeled fume hood where any manipulations are conducted so that misting or aerosolization of the material inclusive of digestions, filtrations, hydrolysis etc.). Ideally these areas should have easily cleaned surfaces (PVC, PP, HDPE, FRP).
2. Carbon filter capture of fume hood draft from
which value may be recovered
3. Borohydride rinse down procedures
4. Enforced secondary containment and prompt spill response
5. Frequent changing of PPE like gloves, lab coat, and use of full face respirators, no mustaches, use of boot covers
6. Maintenance of Pt solutions as Pt (II)
7. No dry handling of platinum salts -- damp only, preferably in glove box
8. No melting of Pt sponge with excessive halide content (salts)

 

[snoman701]

I would add, strong acids should not come in contact with organic compounds without serious consideration for what may happen.

This can range from the use of "piranha" type solutions (strong acid & peroxide) all the way to the use of a charmin plug as a filter.

Review how flash paper is made, or guncotton, to understand the dangers of nitrates with organics.

But everyone should review the following, for how important it is to keep organic liquids such as acetone or alcohol away from strong oxidizing solutions.

http://cenblog.org/the-safety-zone/2015/01/piranha-solution-explosions/

Finally, drug/alcohol was mentioned. I do not drink, but do occasionally use marijuana in a more medical capacity (I have crohn's and fibromyalgia). One thing that is very noticeable is the dulling of the senses, but not in ways that most people will always recognize.

For me, it's the odor of NOx solutions. My high efficiency furnace kicks out some NOx, and in order to enter the garage, I have to walk by it's exhaust. I will routinely smell it heading out in to the garage, but never smell it walking back, after using.

Having went to college and had friends that were HUGE potheads, they claimed (and often did) everything, whilst stoned. The most brilliant minds I have known, spend a majority of their time during their studies under the influence. University of Michigan, graduating electrical engineering with honors. It was no big thing for them, but it's clear to me that that simple diminished sense could have serious consequences in a refining capacity, even if you may think you have full control of the situation. Given that the odor thresh-hold and the prolonged exposure damage thresh-hold are pretty close together, this err in judgement could prove to be a very serious consequence.

 

[chemtag]

I had an accident in the lab performing a fusion. I wanted to perform a fusion analysis of a sample from production. The goal was to practice and demonstrate the procedure to a co-worker while seeing how well that sample material fused under these conditions. I weighted out 3 g of sodium carbonate (Na2CO3), 3 g of potassium carbonate (K2CO3), 4 g of lithium metaborate (LiBO2) and 1 g of lithium tetraborate (Li2B4O7). I then mixed this "with 1.8 g of the sample in a small graphite crucible (we do not have a platinum crucible at work).

The graphite crucible was placed in a small muffle furnace already at ~450 C. A small porcelin lid was placed on top of the crucible, where it sat loosely during the heating process. The furnace was manually ramp'd up from 450 C to 900 C over about an hour.

While the oven was being heated, I filled a 1 L beaker with 100 g of 93% H2SO4 and 400 g of DI H2O. A medium sized stir bar was placed in the beaker and the solution stirred for about 20 minutes to allow the heat of the acid dilution to dissipate. I then moved the beaker onto a small stir plate placed on a sagger lid sitting immediately adjacent to the muffle furnace (and also next to the laboratory centrifuge). I placed a large watchglass over the beaker until it was ready for use.

After the furnace had heated to 900 C and held that temperature for ~15 minutes, I prepared to pour the molten sample into the dilute acid solution. After putting on additional PPE for the procedure, I took the watch glass covering the acid beaker off and turned the stir plate on to get the solution stirring vigorously. This formed a strong vortex in the solution.

I then turned off the muffle furnace, opened the door, and using extra long tongs, lifted off the porcelin lid (glowing slightly from heat) and placed it on the sagger lid. I then lifted the crucible out of the oven by grabbing one side with the tongs. I then quickly poured the molten material into the beaker. Within a second of the molten material entering the beaker, the entire beaker exploded with a loud bang. My extra PPE (namely the aluminized jacket and face shield that were on over my regular lab coat and goggles) protected me from the small amount of liquid that I came into contact with. Glass pieces fell onto the ground, and some was launched several feet into the room, but most stayed relatively on/near the lab bench.

In the moments after the explosion I carefully placed the still red-hot graphite crucible onto a sagger lid on the other side of the room, where there was no risk of it coming into contact with water (which could cause a steam explosion itself).


So, what happened? Fortuitously there is a video of the accident so I can watch it to see if I did something stupid. Unfortunately, to my novice eyes I can't really see anything. Its possible I touched the edge of the glass beaker with the crucible or tongs, but it doesnt look like it. I suspect that I poured the hot material too fast and caused a small steam explosion. The video shows the explosion coming from in the liquid, and I did pour this sample faster than previously (just because I am getting better at it). Perhaps it is also possible I poured the molten material "down" the vortex and it all hit the stir bar/bottom of the beaker, instead of the liquid.

Its now clear that I should have been using a Teflon beaker which would not shatter under the intense heat of a fusion. However, if what I made was a steam explosion, than the teflon beaker wouldn't have prevented this accident (just made it better by not spraying broken glass everywhere). I am not sure if this type of molten-pour fusion is going to be safe enough to continue using. Instead I have read about fusing materials in a crucible at high temperature, letting the whole thing cool to room temp, and then digesting the solid pellet of fused material straight out of the crucible. Does this work just as well? Does it work if I dont have a platinum crucible (I have access to graphite and zirconium right now, and might get a Ni crucible soon too)?