Muradic acid w/Carbon electrodes Hydrogen/Chlorine process

[The Refiner49er]

I hope this is not a stupid question....

The granite you used for the base, is it a particular type? I was not aware the stone was a conductor.

I can truly appreciate these innovations, as I am an inventor at heart as well.

Keep on, you guys!

 

[The Refiner49er]

Wanted to edit my last post after submittal, but don't know how.

One question for dallasgoldbug- where I find the carbon discs?

Thanks!

 

[NobleMetalsRecovery]

The base is graphite, which of course is a conductor since it is carbon. I got it years ago on eBay, it should be available there still.

I just looked, you can get it on eBay. Look up EDM graphite.

 

[jimdoc]

You can get graphite here;
http://www.graphitestore.com/

 

[hungry]

NMR,LL

What exactly is EDM graphite?. I have nearly 12# of assorted blocks, slices, plates and square rods of graphite. Alot of it appears to be machined and has a shine to it. Is this the type you are referring to?

ED

 

[Platdigger]

edit

 

[The Refiner49er]

Randy-

Wanna sell a couple of pieces of that graphite?

PM me if you do.

I am definitely going to build an electrolytic stripper.

Thanks!

John

 

[NobleMetalsRecovery]

For what we're doing here the type of graphite probably doesn't matter much. EDM graphite is just graphite used with a Electro Disposition Machine. It's a way of forming three dimensional parts out of a block of metal. It uses brass wire, electricity, and graphite. Someone else can fill in more details if they like.

 

[NobleMetalsRecovery]

This is after just 5 or 6 hours with temperatures at or below freezing outdoors. The stain from the test solution has a strong purple color.

 

[NobleMetalsRecovery]

I have found that the graphite leaks. It acid (or water) will seep through the graphite. Plus, another problem could be that the acid leaking through it will loose the gold that's in solution because carbon will precipitate out gold from solution. So it may not be as simple as just collecting the solution that seeps through the graphite. If we can't figure out a way to stop the leaking, it would be good to save the graphite base to recover the gold that accumulates in it over time. One way to stop the leak could be to encase the bottom and pressurize it just enough to keep the liquid from seeping out. I think it would only need a few pounds of air pressure.

 

[The Refiner49er]

As I contemplate processing PMs with what I have studied in this forum, it seems to me this type of device is cost effective and efficient.

I intend on fabricating something similar very soon. I am posting some design questions for commentary.

I have worked with glass extensively, and envision a square column made of heavy plate glass, 8" to 10" square and 18" to 22" tall. A frame at top and bottom and sealed well with RTV silicone, a "refiners aquarium" so to say. The base will be graphite, I am thinking about drilling and threading the base for bottom drain(s). Filtration of the solution could be in-line and gravity fed, or pumped; although I have not yet determined the hardware required for this type of filter.

Processing of larger amounts of materials may cause elevated solutions temperatures, and as Irons pointed out, the solubility of chlorine diminishes on increase of temp. Circulation of the solution and cooling may be desirable to maintain an optimal temperature range.

The only significant hazard is the generation of hydrogen gas. A vertical vent pipe would remedy, the rising hydrogen effectively carrying away any process gases along with it.

The power regulation is where I am stuck. Ideally, if the power could be controlled by solution temp, or another process value... the objective is to enable operation without the requirement of constant supervision.

I will post additional info and questions as this materializes.


John

 

[NobleMetalsRecovery]

If you've been following this thread you will remember that the graphite turned out to be porous enough to allow the acid to seep through it. Todays experiment to solve the problem shows the cell immersed in a bucket of water with the water level in the bucket just slightly higher than the acid level in the cell. This water the water has a higher pressure on the outside of the graphite than the acid in the cell has on the inside (inside of the cell) of the graphite. This water any flow through the graphite will be the outside water jacket flowing to the inside acid. This should keep the acid out of the graphite where the gold could precipitate inside the block of graphite by coming in contact with carbon.

 

[NobleMetalsRecovery]

The blotter on the left shows the results after adding one Pentium Pro CPU in the cell for a couple of hours.

 

[NobleMetalsRecovery]

Another spot test for gold. The Pentium Pro CPU is done.

 

[NobleMetalsRecovery]

It looks like some iron when through the graphite block (membrane) and ended up in the solution in the bucket. It looks like rust floating around on the bottom.

 

[OMG]

Someone use something titanium or titanium plated instead of carbon and see how that works.
It will lower the resistance, and won't leak. I'm interested to know if/how fast it degrades.
Then maybe I'll find some for my setup.

 

[NobleMetalsRecovery]

Titanium Corrosion

Titanium is the fourth most abundant metallic element in the earth's crust. It occurs chiefly as an oxide ore. The commercially important forms are rutile (titanium dioxide) and ilmeite (titanium-iron oxide), the former being richest in titanium content. Metallic titanium was first isolated in impure form in 1887 and with higher purity in 1910. However, it was not until the 1950's that it began to come into use as a structural material. This was initially stimulated by aircraft applications. A modern and comprehensive document on the subject is the second edition of the classic CORROSION BASICS textbook.

Although the aerospace industry still provides the major market, titanium and titanium alloys are finding increasingly widespread use in other industries due to their many desirable properties. Titanium is a unique material, as strong as steel with less than 60% of its density but with excellent corrosion resistance. Traditional applications are in the aerospace and chemical industries. More recently, especially as the cost of titanium has fallen significantly, the alloys are finding greater use in other industry sectors, such as offshore.

Titanium is a very reactive metal that shows remarkable corrosion resistance in oxidizing acid environments by virtue of a passive oxide film. Following its commercial introduction in the 1950's, titanium has become an established corrosion resistant material. In the chemical industry, the grade most used is commercial-purity titanium. Like stainless steels, it is dependent upon an oxide film for its corrosion resistance. Therefore, it performs best in oxidizing media such as hot nitric acid. The oxide film formed on titanium is more protective than that on stainless steel, and it often performs well in media that cause pitting and crevice corrosion in the latter (e.g., seawater, wet chlorine, organic chlorides). While titanium is resistant to these media, it is not immune and can be susceptible to pitting and crevice attack at elevated temperatures. It is, for example, not immune to seawater corrosion if the temperature is greater than about 110oC.

http://www.corrosion-doctors.org/MatSelect/corrtitanium.htm

 

[OMG]

So will a titanium anode give off chlorine gas, or will it just form titanium chloride instead?

 

[NobleMetalsRecovery]

Titanium is resistant to dilute sulfuric and hydrochloric acid, along with chlorine gas, chloride solutions, and most organic acids.

 

[Anonymous]

I would resaw the carbon or get thinner sheets and saturate them with
expoxy to seal it then glue that to a solid base to support it.