hi, I’m a newbie to this group. But I do have kind of a PM challenge on my hands. Kind of a cautionary tale, too. And at the outset, I’m glad to have found the “Chemicals” section on this site; I’m applying the advice there immediately. For this info. my family and neighbors are (unknowingly) grateful, as well.
In general, I’m looking for ways of dealing w/ the 500 lbs. or so of crushed ore in my garage, hopefully in ways that are more efficient than what I’ve already tried. I should mention, too, that living as I do in a large urban area, that it’s hard to do ANYTHING unnoticed. Also, FTB, moving to another more congenial location is unlikely.
Background: A year or two ago I made myself a ball mill that’s been cranking out several hundred pounds of fine mesh (<100) of crushed electronics boards. (Unfortunately I’ve had to stop it for the time being. Just too much of the nasty black stuff collecting in the garage). The daunting challenge now is to try to attempt PM recovery. I’ve already made a few dangerous mistakes—pouring acid directly onto fine mesh powder is just one example of something I’ll do more cautiously in the future. Even my high-school age kid told me, “dad, be sure to WAFT, not SNIFF”, as I used to stand over buckets of fizzing glop. And I should thank Lou B, for a recent private email, stressing that probably CN extraction is probably beyond a reasonable threshold of common-sense safety for me, working as I do in a residential neighborhood.
Attempts so far:
1st batch (goof #1-abandoned) pouring a quart or two of HNO3 50% directly onto mesh powder outside in a 5-gal bucket. Copious billows of acrid red smoke. Result: a frothing glopping mass. Values unrecoverable, because of oxides of Pb and Sn started forming in the bucket almost immediately, thus contaminating the ore.
2nd attempt, new batch (in process): starting w/ HCl to remove Sn, Al, and Zn, at the very least. More manageable fumes. I’ve rinsed the batch w/ rainwater and let it dry. I suppose that now I might treat it w/ HNO3, and later AR. Still, lots of acids just for a single 5-gal (50lb) batch
3rd attempt (in process): taking ore already treated w/ HCl (w/ Sn, Al, and Zn removed, in theory), and attempting poor-man’s Parkes’ Process: melting 15 lbs of tire weights, and dunking the ore in a bath, a few pounds at a time. Kind of acrid smelling, no doubt from the remaining trace HCl at 600F. Also, in Parkes’, I’m looking for tips for separating the Zn-PM alloy from the molten Pb; there must be a trick to stirring it in and then floating it off. One problem is that this method would work much better, say, w/ 10 times the molten Pb than I can reasonably manage.
4th attempt (no way): CN. Lou B has already advised me out of this one.
Frankly, between methods 2 and 3, maybe I can get sumpn’ going, but it’s a long haul.
Look forward to following posts, and (hopefully) posting soon,
SamW
In general, I’m looking for ways of dealing w/ the 500 lbs. or so of crushed ore in my garage, hopefully in ways that are more efficient than what I’ve already tried. I should mention, too, that living as I do in a large urban area, that it’s hard to do ANYTHING unnoticed. Also, FTB, moving to another more congenial location is unlikely.
Background: A year or two ago I made myself a ball mill that’s been cranking out several hundred pounds of fine mesh (<100) of crushed electronics boards. (Unfortunately I’ve had to stop it for the time being. Just too much of the nasty black stuff collecting in the garage). The daunting challenge now is to try to attempt PM recovery. I’ve already made a few dangerous mistakes—pouring acid directly onto fine mesh powder is just one example of something I’ll do more cautiously in the future. Even my high-school age kid told me, “dad, be sure to WAFT, not SNIFF”, as I used to stand over buckets of fizzing glop. And I should thank Lou B, for a recent private email, stressing that probably CN extraction is probably beyond a reasonable threshold of common-sense safety for me, working as I do in a residential neighborhood.
Attempts so far:
1st batch (goof #1-abandoned) pouring a quart or two of HNO3 50% directly onto mesh powder outside in a 5-gal bucket. Copious billows of acrid red smoke. Result: a frothing glopping mass. Values unrecoverable, because of oxides of Pb and Sn started forming in the bucket almost immediately, thus contaminating the ore.
2nd attempt, new batch (in process): starting w/ HCl to remove Sn, Al, and Zn, at the very least. More manageable fumes. I’ve rinsed the batch w/ rainwater and let it dry. I suppose that now I might treat it w/ HNO3, and later AR. Still, lots of acids just for a single 5-gal (50lb) batch
3rd attempt (in process): taking ore already treated w/ HCl (w/ Sn, Al, and Zn removed, in theory), and attempting poor-man’s Parkes’ Process: melting 15 lbs of tire weights, and dunking the ore in a bath, a few pounds at a time. Kind of acrid smelling, no doubt from the remaining trace HCl at 600F. Also, in Parkes’, I’m looking for tips for separating the Zn-PM alloy from the molten Pb; there must be a trick to stirring it in and then floating it off. One problem is that this method would work much better, say, w/ 10 times the molten Pb than I can reasonably manage.
4th attempt (no way): CN. Lou B has already advised me out of this one.
Frankly, between methods 2 and 3, maybe I can get sumpn’ going, but it’s a long haul.
Look forward to following posts, and (hopefully) posting soon,
SamW