# An idea for recovering platinum from spark plugs.



## Evan2468WDWA (Jul 9, 2014)

I was thinking about how someone might economically recover precious metals from used spark plugs. I'm not actually planning to do this because I don't have any spark plugs, but I'm curious about what people think of this idea. 

Step One: Grind the out layer of the plugs with a twisted wire wheel brush, and collect the metal dust created making sure to take all the needed safety precautions. 

Step Two: Slowly and carefully put the metal powder into a container of hot concentrated sulfuric acid making sure to take all the needed safety precautions. Wait for the acid to dissolve the copper and nickle. 

Step Three: Wait for the solution to cool then filter it off leaving the precious metals behind. 

Step Four: Use electrowinning on the solution to recover the sulfuric acid so you can use it on the next batch of metal powder. 

So what do you think? If you had enough used spark plugs would this be worth doing?


----------



## necromancer (Jul 9, 2014)

personally i don't know of anyone chasing spark plugs.

i am sure if you went around asking for them you would have more then enough to keep you busy for a long while.

let us know how many it takes for a gram of Pt & how many hours it takes to get that gram.

not trying to discourage you, its just a very small amount at a time. like hard drive platters.


----------



## Pantherlikher (Jul 9, 2014)

As I understand, being a mechanic for almost 30 years, only the end where the spark is produced is lightly plated. Reduces wear or something technical like that.

I used to snip off the end with wire cutters. Prying and bending until it broke off. Never got enough to even think of attempting anything.
But it would seem that after you get a 5 gal. bucket or more, you would process for Platinum and hope to at least see something in the end.

B.S.


----------



## Evan2468WDWA (Jul 11, 2014)

I think I would like to try it. The problem is that my financial situation is so bad right now I couldn't afford to do it even if I could get them for free. I applied for a job at KFC recently so maybe I'll have some money to work with pretty soon.


----------



## necromancer (Jul 11, 2014)

Evan2468WDWA said:


> I think I would like to try it. The problem is that my financial situation is so bad right now I couldn't afford to do it even if I could get them for free. I applied for a job at KFC recently so maybe I'll have some money to work with pretty soon.




hope things get better for you soon !!


----------



## Evan2468WDWA (Jul 11, 2014)

necromancer said:


> Evan2468WDWA said:
> 
> 
> > I think I would like to try it. The problem is that my financial situation is so bad right now I couldn't afford to do it even if I could get them for free. I applied for a job at KFC recently so maybe I'll have some money to work with pretty soon.
> ...


Thanks for the encouragement.


----------



## Dach Savage (Jul 11, 2014)

I have heard that there is a good bit of platinum in aircraft sparkplugs although I have never figured out where and how to get at it. Then again, I read here once that there is gold in poop. Best of luck.


----------



## etack (Jul 11, 2014)

Evan2468WDWA said:


> I was thinking about how someone might economically recover precious metals from used spark plugs. I'm not actually planning to do this because I don't have any spark plugs, but I'm curious about what people think of this idea.
> 
> Step One: Grind the out layer of the plugs with a twisted wire wheel brush, and collect the metal dust created making sure to take all the needed safety precautions.
> 
> ...



sulfuric does not dissolve Cu. Nitric would be best.

Eric


----------



## Evan2468WDWA (Jul 12, 2014)

Dach Savage said:


> I have heard that there is a good bit of platinum in aircraft sparkplugs although I have never figured out where and how to get at it. Then again, I read here once that there is gold in poop. Best of luck.


Thanks for the tip. 


etack said:


> sulfuric does not dissolve Cu. Nitric would be best.
> Eric


For some reason I have a hunch that sulfuric acid will allow for the largest number of reuses with electrowinning. Maybe I think that way because that's what they use in car batteries and they last for a long time. I know that Nitric acid will produce gaseous NO2 which would seem to indicate that the number of uses will be very limited unless I capture that gas somehow. If I can't use sulfuric acid then maybe I should use he AP method. I wonder if the AP method can be done with sulfuric acid instead of HCl.


----------



## Harold_V (Jul 12, 2014)

Dach Savage said:


> I have heard that there is a good bit of platinum in aircraft sparkplugs although I have never figured out where and how to get at it. .


Depends on the plug. I processed several, and found various types of builds. The center electrode was always solid platinum, with varying diameters, and short--connected to base metal in the porcelain. Smash the porcelain with a hammer and you release the platinum. Length of the small piece of platinum? It's been a long time, but memory recalls about 3/8", or slightly less. 

Some of the ground electrodes were also platinum, and of various designs. I processed them by parting off the end (I was a machinist, so that wasn't a problem for me). The recovered pieces were sent to my stock pot, which slowly eliminated the steel, leaving behind platinum. It was recovered years later, when I processed all of my waste material by furnace. 

I have no knowledge of modern day auto or aircraft platinum plugs. The platinum plugs of which I spoke were procured some time in the mid 70's. 

Harold


----------



## CATMAN (Feb 13, 2015)

Hi guys,
New to the forum, just joined yesterday. I own an automotive repair shop and I am going to try refining catalytic converters but never really thought about spark plugs. We change hundreds of them and most newer vehicles all use platinum or iridium tips, but i dont know how much. I do know that some spark plugs cost $15-$20 a piece. I guess I'll have to get me a 5 gallon bucket and start collecting.lol


----------



## Lou (Feb 13, 2015)

CATMAN!

First, welcome to the forum. 
Second, hold your horses, and consider if you really want to attempt recovering platinum from autocatalyst. I can tell you that it is not worth the hassle. Search around and you'll find good reasons why.

Second, spark plugs are quite difficult because the values are usually encased in a zirconia or alumina sheath that is quite hard. Someone here might have a good way of de-tipping them.


Lou


----------



## CATMAN (Feb 13, 2015)

Hi Lou,
I talked to a guy in NJ who refines platinum. He said the easiest way is to saturate water with lye and heat the cat material and that would dissolve the ceramic and you would be left with the precious metals, not refined of coarse. Do you think he is full of it? He seamed legit. I'm just a newbee so maybe I'm easily swayed.


----------



## Lou (Feb 13, 2015)

That works in some instances (all depends on the type of the ceramic) but the fact of the matter is, it's not 100% effective and you'll still need to dissolve them.


Lye is also pretty nasty. One splash in the eye, vision goes bye-bye.

Just proceed carefully. I would just broker catcons and save that money for easier, more rewarding scrap.


----------



## kurtak (Feb 14, 2015)

CATMAN said:


> Hi guys,
> and I am going to try refining catalytic converters



Been there - done that - & I can tell you from experience that you are far better off selling the CATs "as is" to a CAT buyer

When I say been there done that - I mean tried on a large scale at a scrap yard that took in at least 500 & as many as 1000 CATs per month

If you want to leach a few CATs for the purpose of getting some PGMs to play with & learn about PGM refining thats fine BUT----

If you think you can set up to process them on a "for profit" venture --- FORGET IT --- it will cost you more just in dealing with the waste then what you can hope to get out of them

Kurt


----------



## MarcoP (Feb 14, 2015)

Kurt, I've read about your adventure and I was thinking to leach the ceramic with a saturated lye solution and then sell the remainings to a refiner. I guess it would be less expensive, less time consuming, no PGMs losses...so profitable?


----------



## kurtak (Feb 14, 2015)

MarcoP said:


> Kurt, I've read about your adventure and I was thinking to leach the ceramic with a saturated lye solution and then sell the remainings to a refiner. I guess it would be less expensive, less time consuming, no PGMs losses...so profitable?



No :!: 

We tried that to --- Noooo :!: :!: 

I would much rather work with large volumes of acid then large volumes of NaOH especially when you start talking about HOT NaOH :!: 

There are "many" other problems involved with this (NaOH) process - which I don't have time to go into :!: 

If you want to make a profit on CATs --- sell them to a CAT buyer :!: 

This has been Edited from the original which simple said --- Nooooooooo :!: :!: :!:

Kurt


----------



## MarcoP (Feb 14, 2015)

kurtak said:


> MarcoP said:
> 
> 
> > Kurt, I've read about your adventure and I was thinking to leach the ceramic with a saturated lye solution and then sell the remainings to a refiner. I guess it would be less expensive, less time consuming, no PGMs losses...so profitable?
> ...


Then I will definitively use a couple of them for learning purposes only, when I "grow up" I will surely need this experience for dental scrap.

Thank you!


----------



## CATMAN (Feb 14, 2015)

Sorry guys, but as an auto repair shop owner the numbers dont add up. Guys are buying cats from me for sometimes as high as $125 for like a BMW or late model ULEV Honda. They are small scale like driving around in some piece of crap old pickup and buying this stuff. I live near Santa Barbara CA so they prob drive this stuff down to LA then sell to someone else who in turn sells to someone with a bigger operation who in turn sells to someone with a bigger operation who then prob sells to a refiner. If I an getting $50-$125 per cat then by the time it is refined there must be $300-$400 of precious metals coming out of each cat.(for the ones that they pay $125 for) I'm thinking if I can extract any precious metal out of a cat and smelt it then sell to a buyer as is then i should be money ahead. Keep in mind they dont cost me ANYTHING. I know that most of you guys love to refine your metals as pure as possible and I've looked at the picture gallery on this forum and all I can say is WOW amazing pictures! sure I would love to have enough gold or platinum to refine an almost pure bar but right now I'm just wanting to extract the metal. maybe later try and refine some. I talked to a refiner in Florida some years ago and he said that they needed at least 10,000 pounds of crushed cat material before they would process it that would be approx 10 fifty five gallon drums then it would take a year to get paid because they average out the price over that year. My friend owned a wreaking yard at that time and that was too much even for him to think about.
Anyway sorry to get off track. I would love to recover even a small amount of metals from these cats. I have 10 acres in north California with a gold bearing creek and when I find even a tiny piece of gold from that creek I smile from ear to ear. It may have cost more if fuel and time to find it than it is worth but I am the first person on earth to see that piece of gold.
would still like some ideas or inputs on the best ways to remove ANY maybe not all of the precious metals for cats. After all if they are free then why not play with them and learn!
Thanks for reading my rant LOL
Mark (catman)


----------

