With an estimated use of 320 tons of gold a year for the production of electronic devices, such as mobile phones and laptops, “e-waste” may become the focus of a new gold rush. Billions of pounds worth of gold are laying to waste in old circuit boards. Around $15.5 billion make up for total value of gold used in all our gadgets, but only 15% of that is ever recovered.
In 2001, 197 tons of Gold were used , making up 5.3% of the world’s supply. By 2012, that number rose to 7.7%, making up 320 tons. Some of the valuable metals and materials inside the typical phone are, but not limited to:
- Gold: 0.034 grams = $1.82
- Copper: 16 grams = $0.18
- Silver: 0.35 grams = $0.36
- Platinum: 0.00034 grams = $0.02
Although these numbers seem low, compared to a typical gold ore, the gold yield is incredibly high. A ton of gold ore, depending on the source it came from, can yield from 0.3 to 5 grams of gold per metric ton. In comparison, a ton of cell phones can yield as much as 280 grams of gold, and that’s not including the other precious metals and materials. The plastic and glass could also be recycled from used cell phones.
Three different methods are required to extract the precious metals from your cellular devices. The first step would require a cyanide recovery process for the gold removed from motherboards and connectors. During this stage, the gold will dissolve which you will be able to filter out.
The next step would be having you recovering the gold from the chips. This portion requires burning them in an environmentally friendly way, then grinding what is left into a fine powder. That powder is then melted into a crucible with borax and lead, giving you a solid mass of mixed metals. As for the third step, recovering palladium from ceramic capacitors, the process is similar to recovering gold from the chips. You would first crush the capacitors into a fine powder, then the palladium is removed and melted in a crucible with borax and led.
The chemicals and processes required to “surface-mine” these mobile devices individually would not be very cost efficient, but companies such as Umicore in Belgium recycle mobile phones at a massive scale. After the entire process is over, less than .5% of the electronic waste process is deemed unfit to be returned and is instead burned for energy generation.