The ocean has about 20 million tons of gold in it — that’s round 700 TRILLION DOLLARS value of gold! On this episode of Reactions, we discover how, for over a century, folks have struggled to gather it. And we see if, the place they failed, we are able to succeed.

Video Transcript:

The ocean has round 20 million tons of gold in it. That’s one thing like $700 trillion value of gold.

And the cubic mile of seawater behind me has someplace round one million {dollars} value.

So how do I get a few of that?

(vague)Hey, I’m Sam Jones, I’m right here for reactions.

All proper, I’m prepared.

I’m in fact, not the primary particular person to have considered this. In 1872, a British chemist named Edward Sonstadt found that there was gold in seawater, however he didn’t really attempt to get wealthy off of it.

The primary particular person to attempt was New England pastor, Prescott Ford Jernegan in Eighteen Nineties. The story goes that he comes down with typhoid fever. He’s completely delirious, clinging to life and he has a weird dream the place he sees seawater being became gold.

So he survives the typhoid and he’s like, all proper, I’m gonna try this. And he creates what he calls the gold accumulator.

It was primarily a wood field with holes in it that inside had a sheet of stable mercury that was blended with a secret ingredient. After which it had a wire hooked up to a battery that ran by the mercury and electrified it.

Jernegan was promoting this bizarre electrified wood field to folks in order that they might get wealthy fast by sucking gold out of the water.

This can be a chemical course of that scientists typically discuss with as a rip-off, the science simply wasn’t there,

However not all makes an attempt to get gold out of seawater had been scams.

In 1900 inventor Henry Clay Bull filed a patent for a technique of extracting gold from seawater, the place he lowered the acidity of seawater to supposedly pull out dissolved ions, together with gold ions, however there’s no document of Bull even making an attempt his personal machine.

Within the Nineteen Twenties, Nobel Laureate, Fritz Haber spent years engaged on this and truly got here up with what was apparently a legit course of that includes a large centrifuge.

However then he realized he made a quite simple mathematical error early on, and his course of turned out to value extra money than you’d really get again in gold however the place all of them failed, I believe I can succeed, proper?

I imply, it could actually’t be that arduous.

Obtained it.

So we’ll boil off the water in seawater, which can simply depart the salt behind after which I’m gonna try to extract gold from that.

Hmm, now that I’ve salt, I simply have to separate the gold from the opposite stuff in it.

Usually when folks extract gold from rock or sediment in nature, they use a way referred to as a gold cyanidation the place gold is actually dissolved.

Gold cyanidation depends on an oxidation discount or redox response, which is a kind of response the place electrons are transferred from one species or atom to a different.

On this case, oxygen removes electrons from gold atoms leaving them with a optimistic cost in order that they’ll kind a fancy with negatively charged cyanide.

Hey George, can I get a thumbs up for utilizing cyanide on this video?

Whereas I used to be making an attempt to determine tips on how to purchase one thing that’s been used as a chemical weapon to extract gold, I obtained to pondering, how a lot gold might I really get from this?

In 1990, researchers found out that there’s about one gram of gold for each hundred million tons of seawater.

So I boiled down one liter of seawater and seawater incorporates about 50 femtomole per liter of gold, that equates to about 10 picograms.

$1 gold is about 0.01769 grams of gold. So if I simply need a {dollars} value of gold, I would wish to undergo 2 billion liters.

Hmm, okay.

Effectively, a fast name to a chemist ought to assist me type this out.

If I introduced 100 liters of seawater to your lab and I used to be making an attempt to extract gold from it, what would you inform me to do?

– In the event you introduced it to the lab we might attempt to take away it doing one thing like electrochemistry, the place can we attempt to cut back it by offering electrons to it.

So what’s the downside of simply doing that. I imply, simply convey you buckets and buckets of seawater.

– Effectively, my lab isn’t that large. So this may be actually difficult. It might even be fairly costly to move that a lot seawater as a result of there’s so little gold in that water that you’d have to convey tens of millions of gallons.

– There was some work executed the place folks have really eliminated gold from seawater utilizing steel, natural frameworks.

A steel natural framework, or MOF is clusters of steel ions linked collectively by natural molecules. MOFs might be modified to entice completely different molecules of curiosity and their giant floor space means they’ll take in a number of no matter they’re amassing.

– A small piece of steel, natural frameworks say the dimensions of your hand, might need the floor space of say a soccer discipline.

So then what’s the holdup?

– Effectively, these items bind ions, however a number of ions look comparable and given the small quantity of gold you’re gonna get out of the water, it really finally ends up not being value environment friendly.

– I believe should you have been speaking about doing it profitably. Folks would sort of discover that to be a bit of foolish.

Ah, okay. Effectively for now, I’m not gonna get gold out of this, however I did get to go to the seashore to movie this video. So it wasn’t a complete loss.

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