# Best way to proceed with Cats?



## kilo17 (Mar 2, 2013)

So I have gotten the Recovery/refining bug and have several projects going. I have 2 batches of Cats that I have extracted using Steve's method. I have both filtering as I'm typing this. From the pictures below you can see I have a fair amount to process and was wondering what might be the best way to proceed. I guess I'm asking if I should mix it into 1 large batch and process it all at once or process it in smaller batches? There is about 8 honeycombs in each batch. Thank you... Keith


----------



## lazersteve (Mar 2, 2013)

Combined the two batches and cement out the Pt and Pd using zinc turnings. If you're solution is very acidic (ph <=2) then you can use some soda ash to neutralize some of the acid (pH4-5) to save on zinc. 

Once you have the zinced out mixed PGM black proceed with the cleanup and controlled dissolution stages. Be very careful not to over do the use of nitric acid if you are using AR to dissolve the Platinum as it will require you to remove the excess nitric before you can precipitate.

Steve


----------



## kilo17 (Mar 2, 2013)

Would you recommend or discourage doing it in 5 gallon buckets? I guess my concern is the difficulty in dropping with Zinc if I cannot watch the additions like in your video. I suppose I could add the zinc and test with Stannous. thanx... Keith


----------



## lazersteve (Mar 2, 2013)

It's easier to see the end point in clear or semitransparent buckets like I use on the video. Stannous testing will work if your bucket is opaque.


Steve


----------



## kilo17 (Mar 2, 2013)

Here they are filtering, very contrasting colors between the 2 batches, particularly since each one had about 8 honeycombs.


----------



## kadriver (Mar 2, 2013)

Nice pictures.

Please search and read about platinosis on wikipedia as this liquid can give it to you if you get any on your skin.

I started the same way you are going and it took me several months to get a small amount of palladium.

Make sure and use the zinc turnings (available from lazersteve) they work much better than the zinc powder.

I still have some mixed blacks and have yet to get a piece of platinum.

Someone once told me this, "gold and silver refining are like cookie recipes compared to platinum refining".

It is much more difficult with some knowledge of chemistry as a must.

Some of the reactions happen at very specific pH levels, with the level changing as the reaction progresses.

A fumehood is an absolute necessity if you are going to be doing this regularly.

If you get to the level that you are refining your own pure platinum, then you will join the ranks of a very small group of people.

I'll bet that there are less than 500 people on the planet who can refine platinum group metals - probably less than 100 if you are talking iridium, ruthenium and osmium. Of course these numbers are just guesses.

I'll be glad just to get a gram of pure platinum that I refined myself.

Cool stuff!

kadriver


----------



## lazersteve (Mar 3, 2013)

Kadriver,

Back in the early 90's when I graduated electronics school there was an article in a periodical I saw that stated there had only been 14 cubic feet of Platinum ever mined in the history of the world. That's less than the size of some household refrigerators.

Platinum refining requires a lot of finesse and know how you can only learn by practicing, observing, and testing. Reading books is fine for learning the fundamentals, but there is a fine art to actually refining Pt. Just like many other skills, once you learn how to recognize Pt in it's various states, it gets a lot easier. When starting out you must rely on your test solution.

Pt is stubborn to go into solution and requires a strong oxidizer, some heat, and time. Pt also mimics Pd in many of its reactions and can sometimes slip by you into your Pd if you are not careful.

I'm glad you are stressing the safety of Pt refining to Kevin, as safety is the most important aspect of any recovery and refining job in my opinion.

Steve


----------



## skippy (Mar 3, 2013)

Keith, your solutions look nice and rich. You're going to get a decent little return of PGMs. Keep it up.


----------



## kilo17 (Mar 4, 2013)

Thank you for the comments, I am taking a lot of safety precautions. I have a chemical mask, gloves etc and I did look up platinosis. I wanted to share something I did this weekend. I took several of the cats I extracted from previously along with 4 additional honeycombs in a 5 gallon bucket. I had bought a bucket heater and set it to 110 degrees and placed the bucket into a storage container. I decided to heat for 48 hours like mentioned by Steve and I was going to do 3 bleach additions each day. Well after it was going about 6-8 hours I removed the lids and thankfully had my mask on because it let out a large plume of chlorine gas. I added some bleach and repeated it later Saturday night. After 24 hours I checked it and it appeared to be finished, I measured the temp and once it hit over 200 degrees it hit me that the dial is in Celsius. (Forget the fact that there is a "C" on the dial) I turned it off and processed it. I may have list some values but the solution appeared to be way more concentrated. I am planning on doing a comparison if I can get a couple of the same cats on heated vs not heated. The biggest problem I had with the heated solution was that it had way more particulate in it and was much more difficult to filter. Obviously, I made a mistake assuming it was Fahrenheit, but I was impressed with the speed at which it extracted the PGM's... Here is a picture of the bucket heater, the partially melted bucket on the inside and also the PGM black I have obtained thus far. Keith


----------



## nickvc (Mar 5, 2013)

I have to agree with Kevin about PGM refining it really is an art as much as a science and few people ever master it but you have one of them helping you, our very own lazersteve so you couldnt be in better hands. 
The one thought I did have is that depending on the type of cats you could also have Rhodium in the mix..


----------

