incineration question

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beav3r316

Active member
Joined
Nov 9, 2015
Messages
36
Location
Wichita, KS
Hey everyone, I just have a question about the incineration process of my gold bearing filters..

In Hoke's book, she states to throw gasoline on the filters and burn them down... I have read in a few posts here that this is not advocated by our resident experts. I am just wondering if it is because of the safety concern with how ferociously a gasoline fire can burn, especially in the worst conditions outside (Wind, etc..)

..or is the reason we shouldn't use it because the burning of gasoline releases Hydrocarbons. Which may help to volatilize and lose values in the smoke that comes off? (Not sure if that is possible or not with hydrocarbons)... I do know from my studies here that carbon can rob us of our gold, but is that same loss of gold possible from the burning of gasoline? Particularly when dealing with filters?

I only ask because, currently my heat source for filter incineration is sub-par (a propane turkey fryer) and the distance from the flame to where the pan sits is some 9"+ away...While I can crank it up a lot, the use of fuel is exponentially higher.

Is there an additional fuel source I can add to the filters (pre-fire) to help get the job done safely and cost effectively? I have a couple different fuel sources at my house, ...I was thinking maybe denatured alcohol would do a better job if it was the nasty exhaust compounds that were the cause for concern with gasoline? I use it in my Subaru STi as opposed to a methyl mix, so I have plenty of it around...but, I am going to wait until I get some input by Harold or one of our awesome in-house chemists.

Thank you very much in advance for any input... Sorry if this has been discussed in greater detail on another thread, I ran a couple searches looking for it, but everything I came upon was not directly related to this.

..if so, be gentle :lol:

"The author has purposely gone into every
small detail necessary to instruct the newcomer who knows nothing of
chemistry or laboratory technique. From the chemist, who may skip
these elementary instructions, we ask patience with the beginners"....

:oops:

Again, Thank you
Beaver
 
FrugalRefiner said:
First, download one or both of the copies of Hoke's book in my signature line below. There is an Introduction that warns about the use of gasoline.

Second, take a look at the work Deano did on ashing filter paper, starting here in his Things which may be of interest to members thread.

Dave

OLD FILTER PAPERS
These sometimes contain considerable value. Tear off and throw
away any paper that is plainly worthless, and spread out the rest to
dry. When you have several papers, burn them in a frying pan;
pour on gasoline and burn until they will burn no more. If the
remains are very dirty, put them in your sweeps or your paper
storage. If fairly clean, add them to your next lot of filings

Hoke - Refining Precious metals waste page 49


I haven't yet been able to get to the second PDF by Hoke, I have it downloaded, but I'm reading the former a second time right now.

I have also seen and read Deanos study as well, while it does give incredibly detailed analysis of the ashing of spent filter papers, in said experiments, he uses an electric furnace, or "flame".

I do not currently have, or have access to an electric furnace, I do have multiple types of fire. In my initial post, my cause for concern - and reasoning for the post, was to see if there was any supplemental fuel that could be safely added to the filter papers to assist my propane tank/turkey fryer set-up. Sorry if the mention of gasoline made alarm bells go off in your mind. I have access to a full machine shop/fabrication shop, so I will most likely just end up modifying the distance between the fire and the grate where the pot/pan rests... The only downside is I have to drive 45 minutes to get to my father's machine shop. I guess its a good thing I have to go there Sunday

Thank you for the input Dave. I appreciate the reply.

I do intend on making a furnace though, and buying an oxy/acet torch cart for my shop/lab here at home. ...I really want to talk the wife into moving out into the country so I can continue my studies and work in peace. ...I live in the middle of a big city, my shop is in my back yard, but passersby going through the alley probably think I'm up to some pretty nefarious activities.

But, until then, I will have to exercise patience with gold recovery, being extra mindful of the steps and precautions taken.
Thanks again
Beaver
 
Incineration of filter papers in my mind is not much different than incineration of other materials like metal powders, where we may have salts or acids involved.

The goal is to bring the temperature up to volatilize combustibles, and unwanted contaminates, to oxidize if possible the base metals, drive off acids as gases...
Without blowing away our values, or loosing them in the smoke.

Chloride salts when heated can take some gold in the fumes, when heating chloride salts and gold this should be considered, and measures taken to neutralize the acid chlorides, so as not to loose silver or gold in the fumes.

Paper forms carbon, carbon here will not take gold, in fact in this case carbon is a good reducing agent, it can reduce base metal oxide to elemental metal, so the carbon here can make it a bit more difficult to oxidize base metals, if not done properly.

Papers can easily be blown out with the force of a torches flame, fine paper fly ash can carry values if allowed to blow out of your pan.
Heating from the bottom in the beginning can ash paper before you use a torch to finish the job.

Gasoline or other highly flammable liquids can be dangerous because of their volatility, they are not necessary, to incinerate the materials, even a lower volatile material like alcohol is not needed.
High heat from below will get the job done that any volatile added liquid could do.

Harold has made many posts on the method he used, in incineration, and if followed gives good results reading his posts on the subject will help with many of your questions.

I incinerate my materials like filter papers and other powders or materials very similar to how he describes, although I do some things a bit different (depending on the materials being incinerated), sometimes I use a stainless steel pan, sometimes I use a pyro-ceram corning-ware dish an electric hotplate (solid burner) and a torch, or a gas burner and stainless pan and a torch, other times over a coal fire with a torch, there are different methods or materials you can use to get the job done, depending on your material you may choose different methods.

Sometimes I save my filter papers to mix with other metal powders or metal salts to be incinerated, using the carbon of the filter papers reducing nature to my advantage, or using its adsorbent nature to my advantage, with metal salts that tend to melt and bubble when fused and molten, the paper filters help to absorb and dry the hot molten salt, so it can get air (separate), and let gases easily escape from the bottom of the hot pan, through the molten mass, and keep the molten salts from becoming like a hot syrup bubbling and popping large bubbles from and splashing values away with the exploding bubbles, the paper lets this molten salt separate more easily, saving time in the process allowing me to raise the heat sooner, to dive off gases.

My goal is to heat from the bottom drying the papers or metal powders or metal salts, driving off gases of water, and the gases of (former acid) salts, in the case of metal salts they will tend to melt to a liquid before the acid gases off, these can fuse to a molten syrup, when too hot can bubble and splash the values away with the popping bubbles, here lowering heat is needed until the acid salt volatilizes off as a gas, here is where adding the filter paper can help, sometimes I may add a previously roasted batch of the metal powders to this molten syrup to speed in drying and keeping the salts separated to speed in time to process them with heat from under the pan, before the final roasting of the metal powders when heating from above with a torch...

Filter paper can also be added to materials in a furnace melt...

I am tired and beginning to cover to many topics to the point of rambling on, sorry back to your question.

Heat from below (for example in a stainless steel pan) on a gas burner or with a rose bud torch or other high heat source... heating the pan red hot to ash the paper, then torch from the top (being careful to introduce the torch to the materials so as not to blow everything out of the pan, begin with the yellow reduced flame of the torch flame just licking, before bringing it on into the materials, where you may be able to get the hotter blue oxidizing flame up closer, to fully help in oxidization of the base metals, without blowing out ash and values, get the materials glowing red hot, until no more smoke is emitted (gases or fumes of acids...), keep it glowing red (crush back to powders if it fused), stir to expose to air to help in the oxidation process, (or use oxygen from the torch to help in the oxidation process of the incineration).

You can do this several different ways using some different materials, but to begin with search for Harold's post on the subject, they will explain it better without all the rambling I am doing here.
 
Thank you Butcher... You could literally write a novel and I would read, and heed, every word uttered. If it is possible for me to live my trial and error process vicariously through you and the other experts on this forum, I will gladly do so. Any, and every, time.

I have read one post by Harold on a similar thread, but it was one of my 3 am reading sessions and I could only remember how adamant he was on not using gasoline to aide the incineration process. Which made me think that there was a newer/better understanding of the chemical process since the time of Hoke and her book...or that it was far from being a necessity and could be accomplished in a different/safer/more productive way.

Thank you again for your time and wisdom
 
Throwing gasoline on burning filter papers is insane. It is one of the few exceptions to Hoke's teachings that we all agree on. NEVER DO IT. It's good to see that you are reading Hoke. However, if something sounds strange, funny, or dangerous, just don't do it until the experts here on the forum have had a chance to set you straight.
 
bswartzwelder said:
Throwing gasoline on burning filter papers is insane. It is one of the few exceptions to Hoke's teachings....


It "is one of", or it is "the only" exception to her teachings?... ...just want to know if there is anything else in the good book that I should look out for as far as a "no go" situation...

I guess she is quite fond of Copperas, and the general consensus I have seen here is SMB. That is what I use as the brewery store down the street sells it, and Potassium MetaBisulfite as well ...although I would like to just use SO2 if I could ever think of where I could get that locally..



edited to hopefully add clarity...and a letter
 
Ferrous sulfate (copperas) works very well, it can be used to precipitate gold, as well as using crystals to test for gold, it is easy to make with dilute sulfuric acid and clean iron, it is just as useful as sodium metabisulfite, and will do the same thing, there are slight differences in what metals they can also reduce, and how they reduce the gold, its good to have both in your arsenal of tricks in your lab, at times it can be useful to use both reagents, when refining the gold twice, where the second precipitation will not let that last bit of base-metal to follow the gold the first refining precipitation may have let through (double refining and using a different reagent to precipitate the gold in the second refining).

Potassium metabisulfite will work, but I believe the platinum metals react more with potassium salts than they do with sodium salts, one of the members that have more experience with platinum metals would be the one to discuss it use in that situation.

SO2 gas can also be fairly easily generated in the lab, although renting bottles would be easier, but where cost and the amount which may be needed for the small lab, generating the sulfur dioxide gas yourself in your own lab may be more practical.

As far as Hokes book, their are some things that should be reconsidered, that may be suggested, besides throwing gasoline into a fire, like working indoors with highly toxic fumes with just a small box fan in the window, where a fume hood or working out in the fresh outdoors would be a much safer option, using your common sense and understanding the age when the book was written, can tell you that that there are much safer options.
 
beav3r316 said:
It "is one of", or it is "the only" exception to her teachings?... ...just want to know if there is anything else in the good book that I should look out for as far as a "no go" situation...
As I stated above,
First, download one or both of the copies of Hoke's book in my signature line below. There is an Introduction that warns about the use of gasoline.
You'll find warnings for the most dangerous processes there.

Dave
 
butcher said:
...
SO2 gas can also be fairly easily generated in the lab, although renting bottles would be easier, but where cost and the amount which may be needed for the small lab, generating the sulfur dioxide gas yourself in your own lab may be more practical.

As far as Hokes book, their are some things that should be reconsidered, that may be suggested, besides throwing gasoline into a fire, like working indoors with highly toxic fumes with just a small box fan in the window, where a fume hood or working out in the fresh outdoors would be a much safer option, using your common sense and understanding the age when the book was written, can tell you that that there are much safer options.


...yes, Right after I posted that, before I finally passed out, I actually read kadrivers post about making SO2 gas from SMB, pretty neat. Which may end up be how I end up doing it. I have been keeping my eye out for good stuff to make a scrubber system for NOx gas recycling, so once I find those little lab pieces, just using SMB to generate the SO2 will most likely end up being how I do it....unless I stumble upon a local supplier that doesn't have a ridiculous 50 cent a day charge. I had read doing different means for each time to precipitate the gold (as far as first drop, and second drop) will help eliminate the stubborn contaminants .... and yeah, I don't do anything inside... I have a 3 year old and 5 month old and I value their well being more than anything....after all ..they are my reason for doing any and everything.



....and FrugalRefiner, I don't know if the book I downloaded is different from the one that you have, but I don't have an excerpt in mine where it warns against using gasoline... the one I have read she mentions using it multiple times... ...or maybe its in the prologue before the chapter guide and I just seemed to miss it?... I'm not taking this hobby lightly, as I am very aware of what can go wrong if things don't go quite right.

That being said... I have only been at this for a little while, but I literally spend about 10-18 hours a day reading and doing studies (depending on the day, my kids, my wife, and the weather) ...I usually have 10 + tabs open on a couple different window browsers....on my laptop....my desktop...my tablet...and my phone... ...one tab leads to a couple links to another thing....then that leads to a couple more....then more...


Thank you guys for the information, it is beyond appreciated,
beaver
 
FrugalRefiner-

-...after waking up all the way, having my coffee and cigarette... I reread and thought about my two replies to you, and I want to apologize..

...sometimes the way I convey my train of thought can come across and pig-headish and rude, I don't want you to think that I am not appreciative of the information that you have given me, I just wanted for it to simply be known that I have read hoke, and am reading the forum like it is my bible. While, I also understand your reasoning for pointing me towards hoke, my first question could have been misconstrued as to make it seem as if I was simply "wanting the FASTEST way to get gold RIGHT NOW!"...just like a GREAT many posts from new members here is/are. ...That is far from being the case, I just wanted to know if it (gas) was omitted from the process because it created an extra loss of values, or if it was just because it is very dangerous and most of the new people, or people that get into this do it for the wrong reasons and are usually always (from what I have read anyways) wanting INSTANT gratification.

...to me, that is not the case.. Do I want to be a millionaire? ,,sure, who doesn't... but, I don't expect it to happen...not easily anyways.

I read a post by Butcher recently when I was stalking his posts in his profile about the bots being the only ones online learning... He then stated later that even though he has done this for awhile, he still actively searches for information because a person isn't truely ever done learning (paraphrasing of course). When I read that it gave me chills and made me smile... Because I have always been one that wants to know WHY, and HOW something works...not just that it works...

Afterall, if something goes wrong, how are you to understand how to fix it if there is no general understanding of the process that is happening. To me, that is a big problem with the world today. If something works- fantastic, if its broke- buy a new one or have someone else fix it.... ...I have never been, or will be one of those people... I have to know everything, and I will not stop learning until the day I die.... and every single thing I learn, I will pass on to my children if they so choose to learn it. ...That is why we are here afterall is it not? ....we cannot live forever, so, we must pass on our knowledge to the next generation so they may innovate and prosper in ways that we could not yet have imagined... ..or maybe that just my convoluted idealism's ...


again, sorry for my dickhead replies, I truly meant no disrespect

Thanks
Beaver
 
beav3r316 said:
....and FrugalRefiner, I don't know if the book I downloaded is different from the one that you have, but I don't have an excerpt in mine where it warns against using gasoline... the one I have read she mentions using it multiple times... ...or maybe its in the prologue before the chapter guide and I just seemed to miss it?... I'm not taking this hobby lightly, as I am very aware of what can go wrong if things don't go quite right.

FrugalRefiner specifically pointed you to his links, because those links include his editorial notes warning about which of Hoke's techniques are no longer recommended, particularly the dangerous ones: using gasoline as a fuel for incineration, just dumping your waste acids down the sink, etc.

edit: removing Department of Redundancy Department
 
upcyclist said:
FrugalRefiner specifically pointed you to his links, because those links include his editorial notes warning about which of Hoke's techniques are no longer recommended, particularly the dangerous ones: using gasoline as a fuel for incineration, just dumping your waste acids down the sink, etc.

edit: removing Department of Redundancy Department

Ah!... I am with you now! ....usually I am the one preaching to my wife about the importance of grammatical choices and semantics in general... and here I am picking and choosing which words to read.. tisk, tisk. Thanks upcyclist ..I will download his version and give it a read, adjusting my notepad and MSDS binder accordingly.

Thanks again for the insight as to what I was missing out on!
 
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