I already have a Facebook account. My telephone has been changed since that account was created. I have a new number because my phone was off for 2 months.
Is it possible to create a new account, even though I already have one?
Yes I am sure you can... Did you try it?
Yes, you can indeed create it. It did it to for a customer and it worked out!
Yes you can create. May be you need to verify the mobile number
You should be able to create a new account, yes. But you will either need a email address different from the one associated with the first account or create the account directly from your phone via the mobile page (which does not require an email address).
That aside I do suggest to look in into the security and recovery options of your old account. At least delete your old non-existing phone number out of it. For most people the associated mobile number is the only way to perform an account recovery (since they never looked into setting up the recovery options). So you might end up locking yourself out of the old account if you don't update or remove the old number.