When using garden fertilizers (like 15-0-0 or 20-0-0 etc.) to make PMN (Poor Mans Nitric) there is a (good) "potential" for PMN to have chlorides in the resulting nitric
That is because chlorides can be part of what makes up the rest of the fertilizer - fillers &/or ingredients used to "time release" the nitrogen into the soil
That is why in the MANY discussions on this forum PMN is not recommended for dissolving silver
As we know --- HNO3 + Ag + Cl = AgCl --- (& therefore PMN is not a good choice for leaching MLCCs)
Also as we know --- HNO3 + Cl = AR
Therefore using PMN to dissolve base metals & there is also gold present (like gold plated fingers/pins) there is the potential for the PMN to also dissolve gold
Here are a couple threads where this has been discussed before
https://goldrefiningforum.com/threads/costs-of-chemicals.1274/#post-10835
https://goldrefiningforum.com/threads/gold-disolving-in-nitric.1116/#post-9323
Quotes from those threads
For what it is worth
Kurt
With ordinary fertilizers, you can be practically sure that they contain chlorides. Salts used are practically speaking tech grade, without any specs, only for heavy metals and dangerous stuff. I do not recommend these.
But despite the fact that there can be countries, where selling ammonium nitrate is somehow prohibited due to concerns about making explosives... It is fairly easy to source and get in bulk for cheap. Here lowest ammount in gardening store is 5kg bag for like 5-10 euros, depending on brand. However, most of the times, it is mixed with something to deter it´s use in clandestine chemistry. Here, most common additive is dolomite, around several %, which also help to granulate the material, which is then less prone to caking.
Easy treatment is to dissolve the stuff in minimal water, filter the dolomite and evaporate down the water, leaving practically pure salt. Conveniently done in oven at like 150-200°C. This will remove practically all water, without any significant decomposition. If you have any doubts about purity, you can always let the solution crystallize and harvest the crystals.
As a teenager, I used it for making smoke bombs, regularly drying it in our kitchen oven... Not wise, now I won´t do it this way on any circumstances. But I was 15 yo, and heavily into pyrotechnics
Nobody got injured or anything vaporized or messed with it (oven). So some old kitchen oven (not gas one) would be ideal.
Here is another interesting quote from the "cost of chemicals" thread (link) in my last post
Kurt
To the Irons quotation, yes. Obtaining the nitric from the "mash" is sometimes tedious, when distilling. Letting the cake in the flask cool, adding little additional water, breaking the lump in fewer smaller pieces and repeating the distillation can help to squeeze some extra nitric as diluted solution. Most of the times, you will dilute it anyway... Without water addition at the start, distillation is producing very strong nitric acid (over 90% usually), which is very dangerous and nasty oxidizing agent. Also, much more decomposition to NOxes occur.
Since I'm not worried about the Pd, for not at least, shouldn't I just nitric leech and be done? Second reason being I'm almost certain that my 1kg or 2kg of mlccs will be(90%+/-) predominantly magnetic which from my research holds very little if, any Pd within them. So maybe just do nitric leech on all my magnetic and then research and educate myself on Pd recovery and one day hopefully I can recover it?
