1. Using a fake name
This is the reason most facebook
accounts get suspended. What do
you expect when you use the name
of an object as a name? Always use
your real name on facebook and
even if you must use a fake name, it
must still be a normal name.

2. Posting on walls in rapid
succession
When you’re posting stuffs or links
on friends’ wall and groups rather
too fast, Facebook might have a
feeling you’re a bot and kick you
out. Some of these bans can be
automated so be careful.

3. You’re sending too many friend
requests
Sending too many requests or
sending friend requests to people
you don’t know might get you into
trouble. There’s a limit to the
number of requests you can send
daily and you should get a warning
when you reach this limit. Trying to
proceed after you get the warning
might be dangerous. Also, when you
send requests to people you don’t
know and you get reported, I don’t
think it’s good for you.

4. Posting offensive updates and
pictures
You’re supposed to behave yourself
in a public place like facebook,
right? Posting offensive stuffs isn’t
right, you don’t need to be told.

5. Posting duplicated texts in too
much messages
This is spamming and you can get
banned by facebook bots if you do
this. I hate spammers, so does
Facebook.

6. You’re poking rather too much
I’m not sure how far this is true but
it’s rumored that your account
might be disabled when you’re
poking people rather “too much”

7. Your account is a potential risk to
other facebook users
Just a few months back, there was a
problem with facebook
with pornographic pitures all over
the place. It was caused by a virus
and I read that facebook “isolated”
accounts affected by the virus. You
should also be careful with
applications you use on facebook.

8. You’re liking too many fan pages
There’s a limit to how much pages
you can like daily and ignoring the
warning and passing this limit
might get your account in trouble.

9. Suspicious payment information
Paying for facebook advertisement
or game credit with a credit card
carrying a name different from
your facebook name may get your
account disabled

10. Having more than one account
Lots of people have two or more
facebook accounts and facebook
may decide anytime to delete
duplicate accounts. It does happen,
so be careful.

more at(source)
https://greenloaded.com/technology/12-reasons-facebook-account-may-banned/