For the past six years, 22-year-old Boyan Slat has been working to perfect a way to filter vast amounts of plastics out of the world’s oceans. He has a prototype now that might just prove successful.For the past six years, 22-year-old Boyan Slat has been working to perfect a way to filter vast amounts of plastics out of the world’s oceans. He has a prototype now that might just prove successful.