If you are only using a single catalog,You could simply marked unwanted images as Rejected,then could delete them or export all others to a new catalog.This way you don't have to create multiple collections,export them,reimport the corrected images.
You may refer How to flag, label, and rate photos in Lightroom
What you are trying to achieve sounds workable,but make sure when you reimport all the exported catalogs,keep them on your Internal/External drive not the Nas drive.
Thaks fo quick answer.
I make collections by year. Just to short out the list. Then i delete all bad images from collection.
As i have understand lightroom dont delete the master image.
As i mentioned i have 60000 photos. Now in collections about 25000.
To delete the master images of the bad ones?
Why not to storage pictures and catalogs in NAS?
Storage images on NAS but not the catalog,as it needs to be stored on a local disk.