Burn it.
Burn it and use pyrolisis reactors to make something else or just burn it as fuel with the right filters.
And then please use PEF..
This scheme + just burning in general in modern facilitires will be easier and more logical than the population separating the plastics so they get loaded in a ship sent towards some poor place, as we do now.
https://www.scientificamerican.com/article/does-burning-garbage-to-produce-energy-make-sense/
Not ideal, while relatively clean, it still pollutes.. but way better than other options, including direct landfill.
With the ash, you can make ceramics and concrete.
Flyash:
https://www.sciencedirect.com/science/article/pii/S0008884603003867
Bottomash:
http://iopscience.iop.org/article/10.1088/1757-899X/209/1/012082
So we basically would not throw away anything but reuse 100% of it and save money.. but some pollution would occur.