A new study shows that a swarm of hundreds of thousands of tiny microbots, each smaller than the width of a human hair, can be deployed into industrial wastewater to absorb and remove toxic heavy metals.
The researchers found that the microbots can remove 95% of the lead in polluted water in one hour, and can be reused multiple times, potentially offering a more effective and economical way to remove heavy metals than previous methods.
In the new study, the researchers focused specifically on removing lead from wastewater by designing tube-shaped microbots with three functional layers. The inner layer, platinum, gives the microbots the ability to self-propel themselves through water. When the microbots are finished adsorbing the lead, a magnetic field can be used to collect them all from the water. Then the microbots are treated in an acidic solution to remove the lead ions, which can later be recovered and reused.
The microbots can also be reused for further lead clean-up.