# Cemented silver from silver nitrate



## floppy (Aug 23, 2011)

What would be the proper procedure on washing cemented silver from silver nitrate using copper. I have been searching but finding nothing, maybe I am not asking the correct questions for the search. I will keep looking but any input would be appreciated.


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## Barren Realms 007 (Aug 23, 2011)

You can leave it in your container and wash it with water till you have no more color change in the water or you can put it in a filter and wash it that way. A wash with ammona will help insure you have no more copper in your solution.


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## samuel-a (Aug 24, 2011)

Barren Realms 007 said:


> A wash with ammona will help insure you have no more copper in your solution.



Yes.

Cemented silver, dou to its fluffy nature, requires lots of water washes, and even a boil or two. A wash with ammonia will tell you if you have done good or not.
it will turn slightly blue if there's still copper solution trapped in the silver powder.

I think it was Steve that recomended once, between water washed, to boil the Ag powder with dilute 5-10% HCl to eliminate copper, in that case, remaining copper will turn the solution light yellow.


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## kadriver (Aug 26, 2011)

Here is the process I use to wash my cemented silver:

I use a 3 liter glass container to cement the silver. I use copper wire (200 foot roll bought at a yard sale for $.50 cents) and I replace the copper coil with a fresh coil of wire when it looks like the one in use is getting too thin. We don't want any bits of copper wire in our cemented silver if we can avoid it.

Once all the silver has cemented out, I set up a a 500 ml buchner type filter funnel with a 2000 ml filter flask using a vacuum assist and a medium filter paper.

Then, I set two - one quart glass containers to boil 2 quarts of distilled water. I know you can use tap water at this point, but I use distilled water all the way through my silver process. I start the water first because it takes a while to get it to boiling.

I then pour off all the blue liquid (copper nitrate) into a second 3 liter container and leave all the cemented silver in the bottom of the original 3 liter container. I add some hydrochliric acid to the copper nitrate just in case some silver is left, it will form silver chlride and settle. I save this in a third 3 liter container set aside specifically for this purpose - to accumulate silver chloride. I think Hoke calls this a "Stock Pot".

I turn on the vacuum pump and pour the cemented silver and remaining copper nitrate into the buchner funnel - but never more the 3/4 full of silver. All the blue liquid is sucked out of the funnel leaving behind the nearly pure cemented silver. Then I give the silver in the funnel a light rinse with cold distilled water - about 100 - 200 ml.

Then I remove the funnel from the flask and pour the blue liquid from the flask into the second 3 liter container.

I set the funnel containing the silver back on the 2000 ml filter flask and go get the first container of boiling distilled water off the stove.

Using a glass stirring rod, with the vacuum on, I slowly add the boiling water to the funnel and lightly stir the silver. I am very carefull not to get to rough with the stirring as the filter paper could tear and allow silver into the flask. This is easy to fix, but a little care can avoid this hassle.

Once I have the first pot of boiling water through the silver in the funnel, I remove the funnel from the flask again and pour the light blue liquid into my waste container. I rinse the HOT filter flask with more distilled water to get all the blue out.

Then I set the funnel back on the flask and get the second pot of boiling distilled water. I do the same thing, pour the boiling water into the funnel with the silver and carefully stir with a glass stirring rod.

At this point the silver is completly clean and the water in the flask is clear of any color. If there is color, then I get another pot boiling and do the whole process again.

Once completed, I let the funnel sit on the filter flask with vacuum to get out as much of the remaining water as possible.

I then place a large corningware casserole disk on the stove and turn the heat on the lowest setting.

I go get the HOT funnel and dump the silver into the heated corningware casserole dish.

I use a small brush to carefully brush any silver that is in the funnel or on the filter paper into the drying dish on the stove. I save the paper in my silver paper bag for later recovery of the silver on the filter paper.

Using a stainless steel spoon, I spread the powdered clean silver over the bottom of the dish and allow it to completely dry - takes about an hour or so.

When I melt this silver into anode bars for my silver cell, they look almost as pure as the silver that comes out of my silver cell - very clean with probably only a little copper contamination from the cementing process.

This has been the process I use and I have gottne some good results. 

I hope this is helpful - kadriver


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## kadriver (Aug 26, 2011)

I know it is ok to do so, but i would avoid washing cemented silver in hydrochloric acid. Especially if you are going to use it in a silver cell (using cemented silver in a cell is also not recommended). But if that is all you have then that is what may be used.

I did this a while back in an effort to get my cemented silver "extra clean". I boiled my cemented silver in hydrochloric acid, and created a big head ache for myself.

After the HCl boil, I tried to dissolve the silver for use in my silver cell. The resulting silver nitrate turned out very cloudy with silver chloride.

I cemented it back out of the solution and then retried. I even used the sodium hydroxide and sugar method to get the silver chloride out, but it would always turn up cloudy.

I was baffled. I then turned to the forum for help.

Turns out all I had to do to remedy the problem was melt the cemented silver that had been boild in hydrochloric acid and pour it into a METAL container of cold tap water.

This formed shot. I rinsed the shot in distilled water and then dissolved in nitric acid and like magic the cloudiness vanished.

Harold was the one who pointed me in this direction - what a life saver. I think I would still be in my shop to this day trying to figure out what to do to get that cloudy silver nitrate solution to clear up.

Thanks again Harold!

kadriver


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