what is this? Chemical Identification help needed.

[nickton]

Hello. I did a batch of AP leaching and ended up with a flask full of a slightly black colored liquid after filtering with water and am not sure what it is. It looks to me like some sort of colloidal solution, but since it is not red tinted, must not be colloidal gold. The closest I can seem to identify it as is colloidal Platinum (which is blackish), but how can this be? I leached a bunch of gold printed phone boards for a few weeks, which may I understand, have caused some gold to go into solution as a colloid, but it should have dropped back out of a saturated AP solution if I am not correct. I've never seen this before. It does not settle down into any kind of powder while sitting for weeks either.

 

[g_axelsson]

If you are concerned it might contain values, just pour it into a wide and low vessel and let the water evaporate (I use plastic boxes I buy cookies in for stuff like that). Then you could add a few drops of acid and dissolve it again to test with stannous.

If it is colloidal gold then even a very weak aqua regia will dissolve the gold, the surface area would be huge. You could do a small test and see if a few drops of nitric and hcl clears it up and you could test it with stannous again.

Göran

 

[Lino1406]

Nano gold can be blue, depends on how many nanometers is the particle diameter

 

[nickton]

That must be what it was. Amazingly I put it in AR an it all turned yellow:

Thank god I didn't throw it out! :G :G

What I don't quite understand is what made it eventually drop. It appears that just leaving in in its water for about a month caused it to settle. I don't know how colloidal gold works or what takes it out of solution.

 

[g_axelsson]

And have you tested it with stannous?

Göran

 

[nickton]

No but I will. I have no doubt it has gold. Hold on I will get back with you on that.

Okay here it is: Positive, but fairly weak for some reason. I wonder if my stannous is the problem. It seems to take a long time to change color.

 

[nickton]

It looks like my earlier post did not turn up. I must have forgotten to press post after previewing it. But I must mention that the picture I uploaded of a dark liquid is older and when I recently checked that flask (after about a month), there was a settling of black powder that surprised me. Here is the newer photo, before decanting and dissolving in AR.:

Also before AR I heated it which made the powder clump together more, and cleared up the water. This seemed notable so I figured I'd mention it. :mrgreen:

 

[nickton]

It looks like the water must have had 100 nm sized particles, according to that chart. For some reason after reading older threads I had remembered that smaller particles made a darker colloidal gold. I guess I had it backwards.

What does it have to do with pregnancy I wonder? :mrgreen:

 

[anachronism]

No but I will. I have no doubt it has gold. Hold on I will get back with you on that.

Okay here it is: Positive, but fairly weak for some reason. I wonder if my stannous is the problem. It seems to take a long time to change color.

The problem is likely to be that there's very little gold. Why did you assume there were pgms?

 

[nickton]

I thought it might be colloidal platinum because I searched the web and saw samples of it that looked close to the color I had. It can be bought for therapeutic use. Gold is always reddish. I didn't realize colloidal gold could have a black like tint too.
I initially didn't expect to get much AU at all, and even thought I might have nano particles of black paint or maybe rubber. It was a pleasant surprise when the solution turned yellow. I also noticed no precipitated lead after adding sulfamic acid and since the AR became yellow rather than greenish, it appears the gold was quite clean. My AR was probably too heavy with HCL in retrospect, and I only needed a few drops of Nitric acid.

 

[anachronism]

If I may Nick.

Consider your base material and where it came from as a good starting point in terms of which metals may be present. For example, PGMs are not usually present in consumer equipment. Obviously there are exceptions to the rule- but they don't prove the rule wrong.

On the other hand if your base material is high end enterprise telecoms, you can probably say with certainty that the majority will contain Palladium.

So work out what the use was, the kind of budget used to make it, and it begins to make sense.

I was chatting with Nickvc the other day, and we were discussing how many people have posted about Palladium tests being positive in material they are processing but how many pictures of Palladium produced from these tests have we seen? 8) 8) 8) 8)

Jon

Edit for typo

 

[nickton]

At this point I do not consider it to have any pgms anyway, so I guess it's a moot point. I only thought it might be platinum at the beginning and definitely gave up on that idea after using AR. What I learned is that the color of colloidal gold can vary all the way to darker blue/black hues, so if some of one's rinse water after a prolonged Acid Peroxide or copper chloride leach is black tinged, it may indeed contain gold. I hope I didn't give the wrong impression that I was insisting on platinum values or anything like that. It was just an initial speculation based on some searching for examples of colloidal gold on line.

Thanks for the input anyway.