Dealing with Waste

[metatp]

Well the lawn mower blade is now starting to work. It took about a week to really start working. Maybe the surface was treated or something. I now also have an iron rod.

 

[4metals]

When the iron is finished displacing the base metals all that is left in solution is iron. The iron drops out at a pH of 3 to 3.5 leaving the solution barren of metals. The pH will have to be raised to around 7 before discharging it. I have used this procedure in more than 1 refinery and have tested the water before discharging for metals and never had an issue. Today most municipalities have standards for discharging water to ground or sewer, it is wise to know what the governing standards are and have a typical batch of waste tested by a lab using an Atomic Absorption Spec. just to be sure.

 

[lazersteve]

, I have a bucket of copper nitrate

Patch,

I save my copper nitrate to use as an electrolyte for sterling silver. Dilute/concentrate the copper nitrate solution to 6M (moles per liter) or less and use a graphite cathode and anode. Plate out the copper sponge until the solution is an very light blue color and then switch out the positive lead with a sterling silver one. Bag the anode to catch and PGMs or gold that may have made it into your sterling scrap (ie: gold or rhodium plating). The copper will plate out as a moss. Periodically you will need to dip out the moss so it does not fall off the cathode and end up in the solution. The silver will saturated the solution and remain in the bottom of the cell or in solution.

You can also dehydrate the copper nitrate solution and decompose it into NO2 and Copper oxide at relatively low temperatures (less than 150C). The NO2 can be bubbled into water to form nitric acid or into a basic solution to form sodium nitrate which can be used in poor man's AR or nitric.

Steve

 

[metatp]

Thanks for the info Steve.

I am not ready to do many of the stuff you suggested yet, I am still very new and have not considered cells yet. My silver was all from silver epoxy and not sterling (yet). I do have a batch of about 1200g of silver being cemented with copper right now. if i want to save the copper nitrate for possible use later, what can I store it in? I do have an empty 2 liter clear glass bottle that the Nitric acid came in. Will that work?

Regards,
Tom

 

[lazersteve]

Tom,

You can slowly evaporate of the water at low heat (less than 100C) until the copper nitrate forms beautiful blue crystals. Once all the liquid is driven off you can store the crystals very easily in a stoppered bottle.

Steve

 

[4metals]

The moderators would like to thank all of the members that contributed to the original thread upon which this thread was based, as well as those that asked questions showing what was missing. Because of the extra length and interest in this thread we have created the above consolidated version making for an easier read. We encourage all members to read, comment, and ask questions in the original thread, Dealing with Waste.

The Library threads should not be considered to constitute a complete education. Instead, they're more like reading a single book on the subject of recovery and refining. There is so much more information on the forum, and it is impossible to include it all in these condensed threads. Members are strongly encouraged to read the rest of the forum to round out their education.

For those who prefer a printed copy, a pdf file of this thread is provided below.