Suitable idiom for using instead of immunize

Solution 1:

When you boil it to kill the microbes, you are sterilizing the water through Sterilization.

Dictionary.com meaning:

ster·i·lize [ster-uh-lahyz]
verb (used with object),

ster·i·lized, ster·i·liz·ing.

1. to destroy microorganisms in or on, usually by bringing to a high temperature with steam, dry heat, or boiling liquid.
2. to destroy the ability of (a person or animal) to reproduce by removing the sex organs or inhibiting their functions.
3. to make (land) barren or unproductive.
4. Informal. to delete or remove anything comprising or damaging from: to sterilize a government document before releasing it to the press.
5. Informal. to isolate or completely protect from unwanted, unauthorized, or unwholesome activities, attitudes, influences, etc.: You can't sterilize children against violence.

Solution 2:

And by sterilizing you are making the water Potable.

fit or suitable for drinking: potable water.