How to Stop Twitter Updates on Facebook
Facebook and Twitter are social networking sites that allow you to post messages that friends and followers can read. The Twitter Facebook application links the two sites so that Facebook posts are sent to your Twitter feed and Twitter posts (tweets) are sent to your Facebook status. You can stop tweets from updating your Facebook status without stopping your Facebook posts from being sent to your Twitter account. You can completely unlink both accounts so that neither account is updated by the other.
Open a Web browser.
Log in to your Facebook account.
Navigate to the Twitter Facebook application web page (see Resources).
Remove the check next to "Facebook Profile" in the "App permissions" section of the page.
Click the "Want to disconnect your Twitter and Facebook accounts?" to completely unlink both accounts.