A page ownership on Facebook can easily be transferred from one Facebook account to another.
In order to do so, another Page Admin has first to be defined for the page, and it is then possible to remove the other Admin, even when it is oneself.
First, open the Page from the administrator’s profile, and find the Settings menu.
There, find the Page Roles menu entry
Scroll down to the Assign a New Page Role section, and look for the person that has to be added as Admin
Select the corresponding role, Admin, and click on Add
There are now 2 admins – the previous and new one, and it is possible to delete the previous one by pressing Edit button, and then Remove button in the options uncovered
Confirm the operation – and it is done ! The new Admin can now administer the page, and the previous admin has no access to it anymore.