Tiny robots are coming to take away heavy
metal. But don’t worry,
your Mastodon albums are safe.
One of the more challenging aspects of industrialization
is dealing with waste. That waste can include
some pretty dangerous stuff, including heavy
metals like lead, mercury and arsenic. Some
scientists in Europe are proposing a new way
to remove these toxins from wastewater -
tiny robots.
These robots are incredibly simple in design.
Imagine a tube of material that has three
layers. The outer layer is graphene oxide,
which adsorbs lead. Yes, ad-sorbs. That means
it holds particles of the metal against the
surface of the microbot, the way that sand
holds onto molecules of water.
The microbot’s middle layer is nickel, making
the tube ferromagnetic. This allows a human
to control the movement of microbots by applying
an external magnetic field.
The inner layer is platinum. The purpose of
this layer is to provide the microbots with
propulsion. First, you add hydrogen peroxide
to the wastewater. The platinum reacts with
the hydrogen peroxide, causing it to break
down into water and oxygen. The oxygen forms
into bubbles, which escape the microbot tube
through the back. It’s like a tiny jet engine.
According to the scientists, releasing a sufficient
number of microbots into wastewater removes
95% of lead in just an hour. Once the microbots
have done their job, you’d use a magnetic
field to move them to a collection point and
lift them out.
One quick bath in a special acidic solution
later and the microbots are ready for another
go. On top of that, you can reclaim the lead
ions from the solution and reuse them as well.
As for the other heavy metals in wastewater,
the scientists hope to increase the adsorptive
abilities of the microbots to soak those up
in the future. They also hope to improve the
manufacturing process to bring down the costs.
This could help developing countries process
wastewater responsibly while still allowing
them to manufacture the technologies we demand,
such as batteries. It will help cut down on
the environmental impact our consumption has
on other parts of the world. Maybe it could
even help us treat lead contamination in water
supplies and head off future emergencies.
What do you think? Is this solution the right
direction or should we concentrate more on
switching to technologies that don’t produce
so many heavy metals in the first place? Let
us know, and don’t forget to come back and
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