Episode 389 Vanadium

Vanadium is a metal, and by far its greatest use is in steel alloys, where tiny amounts of vanadium improve steel’s hardness, toughness, and wear resistance, especially at extreme temperatures. As I reported in my book What Things Are Made Of, more than 650 tons of vanadium was alloyed with iron to make the steel in the Alaska Pipeline, and there’s no good substitute for vanadium in strong titanium alloys used in jet planes and other aerospace applications.

Vanadium isn’t exactly one of the well-known elements, but in terms of abundance in the earth’s crust, most estimates indicate that there’s more vanadium than copper, lead, or tin. But it’s difficult to isolate, and it wasn’t produced chemically as a chloride until 1830, when Swedish chemist Nils Sefström named it for the Norse goddess of beauty, Vanadis, perhaps better known as Freyja. It wasn’t until 1867 that pure vanadium metal was isolated by British chemist Henry Roscoe, whose work on vanadium won him the name of the vanadium mica roscoelite.

As a mineral collector, I’m attracted to vanadinite, lead vanadate, because it forms beautiful hexagonal crystals, often bright red and so abundant from one lead-mining area of Morocco that excellent specimens can be had without mortgaging your house. Some vanadinite crystals are like perfect little hexagonal barrels, and others can form needle-like spikes around a central crystal, making the whole thing look like a cactus with caramel-orange spines.

Some of the vanadium for making steel alloys comes from primary mined vanadinite, but much more was once produced as a by-product of phosphorous manufacture, because it’s commonly associated with phosphate rock. And today, a lot of the world’s vanadium comes from refining crude oil and from fly ash residues, which are products of coal combustion. I got curious about why vanadium metal is so closely connected with these organic deposits.

Crude oil actually has lots of trace elements in it, including metals like gold, tin, and lead, but by far the most abundant are nickel and vanadium, as much as 200 parts per million nickel and 2000 parts per million vanadium in some crude oils, especially heavy, tarry oils like those found in Venezuela. In some oil, the nickel and vanadium can add up to 1% by weight of the oil, an incredibly huge amount. Refining Venezuelan crude gave the U.S. a lot of vanadium back in the late 20^th century. But why is it in there?

Oil and coal are both the result of decaying and chemically changing plant matter. Forget dinosaurs; virtually all oil, natural gas, and coal comes from plants – usually marine algae for oil and gas and more woody, land-based vegetation for coal. There’s a class of organic molecules call