An amazing recipe for producing clean energy!

MIT engineers discovered that when pure aluminum from soda cans is exposed to seawater, it creates bubbles and naturally generates hydrogen.

This type of gas can be used to power an engine or fuel cell without producing carbon emissions. Furthermore, this basic reaction can be sped up by including a common stimulant: caffeine.

In the study, published in the journal Cell Reports Physical Science, the scientists showed that they could produce hydrogen gas by dropping pre-treated pebble-sized aluminum pellets into a cup of filtered seawater.

The aluminum is pre-treated with a rare metal alloy that effectively washes the aluminum into a pure form that can react with seawater to generate hydrogen.

The salt ions in the seawater can in turn attract and recover the alloy, which can be reused to generate more hydrogen in a sustainable cycle.

The team found that this reaction between aluminum and seawater successfully, if slowly, produces hydrogen gas.

They threw some coffee grounds into the mixture and, surprisingly, found that the reaction rate sped up.

Ultimately, the team discovered that a low concentration of imidazole—an active ingredient in caffeine—was enough to dramatically speed up the reaction, producing the same amount of hydrogen in just five minutes, compared to two hours without the added stimulant.

The team is working to develop a small reactor that can be operated on a naval vessel or underwater vehicle.

The ship will carry a supply of aluminum pellets (recycled from old soda cans and other aluminum products) and a small amount of gallium, indium and caffeine.

These components can be periodically fed into the reactor and some of the surrounding seawater to produce hydrogen on demand.

The hydrogen could power an engine to power it or generate electricity. “This is very interesting for marine applications, like boats or underwater vehicles, because you don’t have to carry seawater, it’s readily available,” said lead author Ali Kombargi, a doctoral student in MIT’s Department of Mechanical Engineering. “We also don’t have to carry a tank of hydrogen. Instead, we’ll carry aluminum as a fuel, and just add water to produce the hydrogen we need.”

The MIT team is working to develop efficient and sustainable ways to produce hydrogen gas.

Hydrogen gas is seen as a “green” energy source that can power engines and fuel cells without generating emissions that lead to global warming.

But one drawback to fueling vehicles with hydrogen is that some designs require carrying the gas on board like conventional gasoline in a tank, a risky proposition.

Instead, the team looked for ways to power vehicles with hydrogen without constantly transporting the gas, and found a potential solution in aluminum, an abundant and stable natural material that undergoes a straightforward chemical reaction that generates hydrogen and heat when it comes into contact with water.

Source: Interesting Engineering