We get platinum from road dust

You have already given the girl a ring made of a coin . Of course, she was delighted, but next time she asked for a real jewel. Money for the jewelry salon is still not enough. What to do? After all, it already has a gold ring since 2013, when you smelted gold from old microcircuits , and there are no more microcircuits left.

Fortunately, there is another option. Another noble metal is literally lying underfoot. If you did not know, in ordinary road dust on road asphalt there is a very high concentration of platinum, since many vehicles use platinum catalysts. So, we take a brush and go on the highway to collect precious dust.

The instruction for the extraction of platinum was published in Ammen’s book, “ Recovery and Processing of Precious Metals ”.
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See also O.E. Zvyagintsev, " Refining of gold, silver and metals of the platinum group " (pp. 120-127).

An American amateur chemist named Arthur and his friend tested in practice the platinum method of refining described in textbooks and recorded a video . First of all, the guys collected a bag of dust from the highway.



It should be sifted, discarding large pieces, pebbles, cigarette butts and stuff. The platinum particles are very small, sometimes the size of just a few atoms, so you should filter as carefully as possible: through a coffee filter.



At the exit we have a large pile of dust, mainly from particles of concrete and rubber.



The smallest filtered particles fall asleep in a glass and weigh. Arthur got 146 grams of dust: this is just for the first test. To make a real platinum jewel, you have to collect more dust.



Dust mixed with sodium carbonate and melted in a furnace to a state of syrup.



A drop of metal will settle at the bottom of the glass.





This piece needs to be ignited to burn impurities.



At the bottom of the glass from the furnace there is a tiny ball made of an alloy of metals with a very high melting point, that is, of platinum group metals.





The ball is ignited to the melting point of platinum in order to finally remove impurities.





The ball is already shiny. From 150 grams of dust, an ingot with a diameter of 0.58 mm (0.33 mm in the narrowest point) turned out.



In the magnifying glass it is very clearly visible, but it is unlikely to weigh it: the scales do not take that weight.

Then dissolve the ingot and precipitate platinum with ammonium chloride.



The whole process is documented on video.



Separating silver and other trash impurities, we get a grain of platinum. The author has calculated that about 6.7 grams of precious metal comes out of a ton of road dust.



6.7 grams of a ton is a lot. The authors of the video believe that roughly the same concentration of platinum in mines in Russia and South Africa (South Africa accounts for 68% of world production of Pt).