Drop it like it's Hot (chemistry questions about dropping the gold)

[snoman701]

If you can read a newspaper through it clearly or shine a laser through it clearly then it's clear. 8)

Whatman number 1 papers will take a solution to crystal clear.

I am using a whatman 44 (ashless)....3 um retention. Got them really cheap.

 

[snoman701]

I keep saying the same thing, but somehow the message is not getting through. Just try leaving a solution sitting for a day after denoxxing (before dropping the gold), you will see the fine layer of sediment settle.

Your solution appears clear, but likely has very fine powder in suspension. Only experience will teach you the difference between a solution that is 100% clear and one that is not.

No, it wasn't getting through....sorry. I'll give it a try...

 

[anachronism]

If you can read a newspaper through it clearly or shine a laser through it clearly then it's clear. 8)

Whatman number 1 papers will take a solution to crystal clear.

I am using a whatman 44 (ashless)....3 um retention. Got them really cheap.

That's better than the ones I use so you should get perfect results- vacuum assisted I assume?

 

[kernels]

I keep saying the same thing, but somehow the message is not getting through. Just try leaving a solution sitting for a day after denoxxing (before dropping the gold), you will see the fine layer of sediment settle.

Your solution appears clear, but likely has very fine powder in suspension. Only experience will teach you the difference between a solution that is 100% clear and one that is not.

No, it wasn't getting through....sorry. I'll give it a try...

Now I really hope you see the settled powder, otherwise I will look pretty silly! But it can't hurt to try it anyway. I can just advise the technique that I have found to consistently give me cleaner drops. I am a believer in giving solutions time to settle.

anachronism - do you need a vacuum setup for the #1 or will clear liquid pass through OK by gravity ?

 

[anachronism]

You need the vacuum if you are using circular filters because it holds the paper down so that no liquid can pass without going through the filter. If the vacuum stops on a buchner the first thing that happens is that particles go through and it's a real pain.

 

[kernels]

Unfortunately my only experience in this matter is that two coffee filters are completely useless at removing the fine (lead chloride ? silver chloride ?) particles. Generally I'm in no rush, so happy to let it settle for a day or two before separating off the clear solution.

 

[anachronism]

Unfortunately my only experience in this matter is that two coffee filters are completely useless at removing the fine (lead chloride ? silver chloride ?) particles. Generally I'm in no rush, so happy to let it settle for a day or two before separating off the clear solution.

Here's what I used to do before I got he Buchner.

Rough filter using single coffee filters. Then use 2 once, then use three and pass it through the same filters a few times.

 

[snoman701]

You need the vacuum if you are using circular filters because it holds the paper down so that no liquid can pass without going through the filter. If the vacuum stops on a buchner the first thing that happens is that particles go through and it's a real pain.

No, I use a cone funnel, then fold the filter paper in to a cone, and just always make sure I don't pour over the filter.

I'm still using what I get cheap or free....in time I'll decide what I *want* to use. It's clear that I need a good vessel JUST for dropping gold in. New & unscratched!

I'm not a big fan of the buchner funnels right now. I have them, but I haven't had good consistent vacuum, so I haven't been using them....and, I'd have to cut the papers down to fit, so what's the point. Actually, I haven't used a buchner since I was using coffee filters. I clogged one of them up with the fines that pass through the coffee filter. Not quite sure how to get those out...maybe boil in AR. If that doesn't work, I'll try throwing it in the kiln and annealing it. That's how we used to clean used glassware...just send it to the glassblower.

I really think my biggest problem with the button I posted is my melting dish. I should photograph it. I bought it at a flea market a long time ago just for the handle. Time will tell.

 

[snoman701]

Unfortunately my only experience in this matter is that two coffee filters are completely useless at removing the fine (lead chloride ? silver chloride ?) particles. Generally I'm in no rush, so happy to let it settle for a day or two before separating off the clear solution.

That, I completely agree with! I had the same problem with the coffee filters. It may have been lead or silver, I always assumed it was from the glue holding ic chips together.

I'd be happy to have it either of those, should make it easy to get the buchners clean!

 

[snoman701]

Unfortunately my only experience in this matter is that two coffee filters are completely useless at removing the fine (lead chloride ? silver chloride ?) particles. Generally I'm in no rush, so happy to let it settle for a day or two before separating off the clear solution.

Ok....tried it. No white powder.

If you'd like to try some "proper" filters, pm me your mailing address. Least I can do.

No attitude or anything intended btw...I appreciate any and all help. I like knowing other options as well!!




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[kernels]

Unfortunately my only experience in this matter is that two coffee filters are completely useless at removing the fine (lead chloride ? silver chloride ?) particles. Generally I'm in no rush, so happy to let it settle for a day or two before separating off the clear solution.

Ok....tried it. No white powder.

If you'd like to try some "proper" filters, pm me your mailing address. Least I can do.

No attitude or anything intended btw...I appreciate any and all help. I like knowing other options as well!!




Sent from my iPhone using Tapatalk

Did the gold drop clean then ?

 

[snoman701]

Won't know until it settles. It was more brown than black, that's for sure.

If I don't get a clean button on this round, I'll likely have to inquart to rid of pgm's.

Sound like an appropriate plan???

 

[Shark]

As for filtering, I use a charmin plug. It stops fine particles that can slip through common filters.

 

[g_axelsson]

Once I bought proper filter papers I never looked back. The only thing I use coffee filters for today is cemented copper. Anything that slips through there is not worth chasing.

Göran

 

[anachronism]

Once I bought proper filter papers I never looked back. The only thing I use coffee filters for today is cemented copper. Anything that slips through there is not worth chasing.

Göran

I use them still for rough filtering large volumes Goran- makes the vacuum filtration later a lot faster when you've got the serious gunk out of the solution. I've used loads this week filtering the Nitric washes on the jewellery slags.

I completely agree though- I remember the first time I used a vacuum setup with proper papers. I nearly cried when I realised how much time I had wasted before. 8)

 

[upcyclist]

I'm in the same boat--the old coffee filters mainly get used for waste processing now. I'll use a couple to filter decanted stockpot solutions, just in case there are floaties with PMs in 'em

I use #1 or #2 filters (which one depends on how much I care) in a Buchner with a simple hand pump that came with the funnel as a kit. Works great for my level of work.

 

[patnor1011]

I do use coffee filters when filtering AP solution due to their size and shape which will fit my strainers. For AR or gold chloride solution I do use buchner and proper filter papers which I cut to desired size.

 

[snoman701]

Spent some time on this this morning.

The copperas, posted above, is the result of not having enough water and too fast of a crystalization.

When I added excess water, 50% of it was immediately soluble. The other 50% needed a little more sulfuric acid to turn clear.

Now it's all occupying all of my crystalization dishes, as well as other dishes in the oven. After that, I'll dissolve it again and do a hot filtration and I should be good to go with it.

So if you are recrystallizing oxidized copperas, make sure you do so with enough water for it to all dissolve cleanly.