dtectr/Jordan,
I guess the first thing I will address here is the fact that you found my commentary “highly insulting”, that was not my intent. It seems you latched on to my final sentence (since you quoted it alone) and taken by itself, out of context, I can see it being taken as an insult perhaps. However it seems you entirely missed the proceeding paragraph in which I wrote...
“Shortcuts tend to bite you in the ass and can be costly in lost values. To be fair, because of experience I at times take shortcuts when I deem it appropriate for the material I am handling. Despite that, it still bits me in the ass occasionally and costs me 4 times the labor to correct it than I would have spent if I had not skipped a simple step in the first place”
I went out of my way to be clear saying that I have taken shortcuts because I thought I was “slick” enough due to my experience to get away with it, only to find out I was wrong at times (and it bit me in the ass) causing me to spend up to 4 times the labor than I should have needed. There are more types of different precious metal scrap materials out there than there are members here. Every type you go to process you will have judgment calls to make as to the best process and what hurdles and contaminates you need to be aware of for that type of scrap. The point being that I find it hard to understand how my final sentence highly offended you when I clearly stated that I am guilty of the same and include myself in that group.
You had also mentioned “how do you know I ignored proper refining practice?”. Even upon rereading my post I fail to see where I said that you did, just that one should be careful of the potential consequences if you do. Again, I did clearly say “I have" at times however.
Moving on I am thankful for your concern as to my edification in regards to surfactants via Wiki. I would however be wary of citing Wiki as the final word for things, it is great for general knowledge but can be dicey on more technical subjects (personal opinion).
Yes, I am familiar with surfactants and yet claim no great expertise but use them to great advantage according to need in refining and daily life. Surfactant however is actually a rather generalized term that is greatly dependent upon what you are trying to accomplish. It can be counter intuitive to many by generalizing and just saying a surfactant is a compound that lowers the surface tension of a liquid. Are you trying to wet something, a floatation cell, emulsify, to name a few, as they are very different functions all performed by surfactants. In your example of miners panning gold and their use of detergents, they would have been better served in using a wetting agent instead, unless of course there were oils present. An inexpensive one that is easily procured is Jet-dry used in dishwashers. Another suggestion that may benefit those that lack the equipment for incineration of oil contaminated scrap is the use of water and NaOH to make the oils miscible in the water. More specifically in this case it should probably be called soluble as I do not believe (I am not sure) it is infinitely miscible as it forms an alkali salt of the oil present (chemists chime in). You had also mentioned ionic- and anionic surfactants. I imagine you were referring to cationic and anionic and the polarity of some surfactants but chose not to delve into those that are non-ionic or zwitterionic and therefor confound the less informed. Needless to say it is a big subject that is not necessary at the moment.
If you have great experience however in this field (as implied) that would benefit us in refining I would greatly enjoy a thread that you could start dedicated to this interesting topic. It has been discussed in many threads in many iterations with multiple variations on theme and application. The forum would be in your debt to have someone that is well versed and experienced to discuss this in detail. Those with the greatest interest would be the miners in dealing with floatation dynamics, but others including myself would find benefit and applications in our refining as well I am sure.
So in the light of me leaving something of value in my post and staying a bit more on topic instead of just spending time on replying to the perceived injustice you felt...
You have been here less than 2 months and I have been scarce here lately, it is fair to say we do not know each other. So I should mention that I run sulfuric stripping cells (frankly I do not think I have ever talked about them here, oh well) that range from small single item cells up to those that process 4 kilos at a time. You had mentioned that you de-plated a mixture of connectors, pins, and watchbands. Pins and connectors can have lithium and mineral oil based compounds used on them (particularly mil spec items), and gold plated watchbands that are not new will have body oils on them obviously.
Having said that I do not see oils as the culprit in your lack of settling. But I was replying to oils, detergents, and incineration, so that is what I addressed. More than likely it is just temperature currents created within your solution as you dilute your sulfuric acid, the reaction generates a lot of heat and any spongy mass will be self insulating within your solution. To paraphrase Barrens, patience can be a virtue. If you are following direction from Steve (a great guy that knows his $#%&) you will more than likely move on to a nitric or HCl step next to remove your nickle and copper from your gold (beware of cadmium and beryllium that are almost always present in gold plated spring connections, but not uncommon in others), probably with heat. Once you start removing your contaminates from your “gold” sludge then you will really see clumps of black spongy material coming to the top of your solution. The lack of black foam on the top of your solution is actually one of your best indicators as far as the endpoint of this step. Take it slow as it is incredibly easy to overflow a beaker only a third full when using heat (it will really sneak up on you if you add your acid first, then add heat).
You seemed surprised in your commentary as to the copper being in your gold sludge. You will always have nickle and copper in your solids from a sulfuric stripping cell. It is dependent upon your cell design, sulfuric concentrations, and temperature, as to how much you will have. As a catch-all way of saying it since I do not know your cell parameters, the more bubbling you see at your cathode the less efficient your cell is operating. The less efficient your cell is operating, the more nickle and copper you will have in your sludge. I have seen cells still actively stripping gold yet produce a sludge that is 2/3rds copper and nickle by volume. Proper concentration of your sulfuric is the most important factor of the 2 as to not putting nickle and copper into your solution as a sludge. Heat here is also a culprit of course. If both conditions exist you can end up with a runaway cell reaction that will peg the amp meter and boil the cell. It is very important to minimize the exposure time of your concentrated sulfuric to the atmosphere. Do not underestimate sulfuric acid's affinity for water. At 4-6 inches distance you can watch the water vapor come off of damp lab gloves into your solution of concentrated sulfuric.
Just as a by-the-way safety note in case someone thinks they are “slick” and wish to enclose a cell including the anode and cathode in order to reduce this take-up of water. You are generating oxygen and hydrogen in a sulfuric stripping cell and having sparks generated as electrical connections make and break. Explosions are bad enough, but you sure do not want one in the proximity of concentrated sulfuric acid. Always have proper ventilation of cells when in use and keep them closed when not.
Now if anyone thinks they are really “slick” and think you have found a way around the hydrogen/oxygen/spark problem in a confined space you should know that the hydrogen is generated at the cathode and the oxygen at the anode. If you wish to discuss that privately PM me.
I should be clear, I am no chemist but in an oft repeated phrase of a good buddy of mine and to add a bit of levity “This is not my first rodeo”. In the interest of full disclosure I should also warn you that beyond being a bit backwoods country I am also without education as I failed to graduate beyond an 8th grade level in school. Buyer beware, whoops, its all free.
Jordan (if it is ok to call you by that considering the circumstance), in some of the above I have been a bit of a smart%$#, it is however accurate and factual based on personal experience not just armchair commentary. If I share something that is purely opinion or conjecture on my part I label it as such. Your fast rebuke when I had (in my opinion) added something of value to a thread dismayed me. It did not help when you followed up such a commentary by questioning my competence to have an opinion since you do not know me. I truly did not mean to “highly insult” you or even to moderately do so.
Since I do not know you this could easily be a one-off misinterpretation, but on the surface of things I would hope that you are not thin skinned. I am often limited in my time to read the forum and post to it so I may be short, direct, or just give a bullet point. I seldom write long posts unless it is a topic I am greatly interested in or I am irked, as I am not a typist. Typically I do not have the time to worry about being delicate and sensitive as to what I say or tailor my comments to one individuals sensitivities even if I know them. I tend to write to the general forums benefit while addressing the issues in the thread.
You will find that the members here that have the greatest experience and knowledge to share (not that I count myself among them) have the same tendencies (factually based, no nonsense answers, and limited coddling). It is a shame that some see it as rude or insulting when it is only a matter of expediency. Please do me but one favor, if you still have a negative opinion as to me or my character and see no value in my commentary, let me know so I do not waste your time or mine. I will refrain from answering questions you post. No harm, no foul, or ill feelings.
Something that can save the entire forum much grief and useless reading (half my post is useless since I was replying to someone that I offended) is that if someone feels offended, send a PM to the counterparty. 9 out of 10 times it is unintentional and we can all edit our posts.
As to my refining content in this post, if I have brought questions to your mind as to sulfuric stripping cells I would gladly answer anyone's questions as time allows. If I am slow, I am sure others will help with perhaps greater experience than I can offer.
. I believe turtlesteve & I were actually asking if anyone had used any such additives in their processes & if so, the benefits/risks of doing so. When you're waiting on material to process, you have some time to think, & you can come up with some interesting "I wonder's...?" i'm sure you're more aware of that than I, given your longer experience in this field. i think that's where this train jumped the track. And I would still like some feedback from anyone with such experience. (The terms "ionic" & "anionic" are used by the residential cleaning product industry, since we were discussing dish detergent, i thought it better to use terms found on the labels, in case someone wound up looking for them).
