# How accurate is this article?



## Evan2468WDWA (Jun 13, 2014)

How accurate is this article? 
http://www.techradar.com/us/news/computing/pc/the-weird-and-wonderful-materials-that-make-up-your-pc-1089510
This article makes it seem like every single component in a computer has valuable materials in it. Is that true? I can't help thinking that at least some manufactures would try and make due with cheaper materials for at least some of the parts.


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## pgms4me (Jun 14, 2014)

That article is 100% true and well written.Given in it's contents are only some examples of what is used in a few of the general types of more common components.There is much more that was not covered as the purpose of the article was just an eye opener..Those components covered are not just in computers,but most types of electronics that have a pc board.even more so in industrial test equipment and telecom boards. Yes, the materia used seem exotic and expensive,but such tiny amounts are used, that the expense is not high. Thank you for sharing the article.This type of information is not widely available.


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## Anonymous (Jun 14, 2014)

Pgms is quite right. It's accurate. 

Another thing is the relevance of the quantity of raw product to get a meaningful amount of the precious metals. For the vast majority of home refiners, the percentage of precious metals by weight form IT products is completely irrelevant because they could never accumulate the quantities to make recovery worthwhile. It's sad, but it's also very true.

It truly is an industry based upon the economies of scale when dealing with the non specific equipment.

Jon


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## Evan2468WDWA (Jun 18, 2014)

Thanks for the answer pgms4me and spaceships. Electronics are some pretty amazing machines. I guess I'm so used to them that its hard not to take them for granted. I've been doing a little reading about them and I found thislink to be helpful.


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## Tub Buster (Jun 19, 2014)

In general, electronic waste is processed by:

1. Removing high grade components for labor-intensive processing.
2. Depopulating the printed circuit board.
3. Separating the copper, usually by incineration.

I've been doing some experiments with step #2 in this process. By using various dilutions of so-called "Basic Piranha" solution (sodium or potassium hydroxide in water, plus strong hydrogen peroxide), the solder is removed, with little effect on other metals except aluminum, which is also removed. The photo below shows that the green solder mask is removed, and you can see that nearly all the solder is gone from the Pentium 4 CPU. The RAM chips and other surface mounted components come off easily with a little pressure from a spatula.

The finger connectors show that some of the gold was dissolved by the process, so this is an indication to remove gold-rich pieces first, and to use a weaker dilution.



> *SAFETY:* Sodium hydroxide (lye, caustic soda) is one of the more hazardous chemicals we use. It forms a corrosive mist when added to water which is easily inhaled. It is particularly harmful to the eyes. Adding hydrogen peroxide increases this danger considerably, so the smallest amount possible should be used.
> 
> The waste water from this procedure contains lead, which is a cumulative toxin. It may also contain silver, so it should be saved, concentrated and smelted.






So it looks like boards might be depopulated with lye+peroxide. In any case this is a good way to remove solder before incineration, cutting down on lead fumes.

* * *

One thing that struck me about the magazine article was the information that hard drive platters contain aluminum + magnesium. Aha -- finally a use for these things. There is a very useful alloy called Zamak or ZA-27, that is made from 28% aluminum, 70% zinc, 2% copper, and 0.02% magnesium. The magnesium is present in a small quantity and yet it is vital to the performance of the alloy. Now here is a source. You can fill your melter with aluminum heat sinks, zinc wheel weights, and a platter and a bit of wire, and what you'll get after it's all melted in a very castable (at 530 degrees C.), low-temperature melting alloy (i.e. a pot metal) that has metallurgical characteristics close to those of mild steel. 
For more details, see www.matweb.com

What can you make from it? Clamps for your glassware! Most glassware clamps are made from pot metal, plated with nickel. A kettle clamp will cost over $100. 

You can nickel plate without electricity as follows:

Add:
nickel chloride, 5 oz/gal or 30 gm/L.
sodium hypophosphite, 1.5 oz/gal or 10 gm/L.
sodium acetate, 8 oz/gal or 50 gm/L.

Use at a temperature of 88 - 94 degrees Celsius. Agitate occasionally. 
Keep the pH between 4 and 6 with sodium hydroxide.
Add small amount of stock as it is used up.

Rate of deposition: 15 microns per hour. That's 600 microinches.
The hardness can be almost doubled by heat treating.

Note: This formula is for plating on iron. I haven't tried it in zinc/aluminum alloy.


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## Evan2468WDWA (Jun 21, 2014)

Thanks for the information Tub Buster. Very useful.


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