[lukan]

You might want to learn something about engineering first. And run some numbers.

And read about them, who tried something way less ambitioned:

https://en.wikipedia.org/wiki/The_Ocean_Cleanup

And still were not that effective.

[boffinAudio]

Oh, this is just a thought experiment, the engineering isn't within our grasp.

I'd imagine some sort of floating device which can build copies out of itself with the plastics it finds is not far away, but it probably does involve a fair bit of science before it becomes more than just fiction..

[lukan]

If we would have that tech, we also could then release the engineered plastic eating bacterias. Way easier.

But currently we want some plastic to remain intact.