There is no concept of an actual clipboard in web applications; in standalone applications, sure, but in browser based applications. If you want to persist state across pages, there are two ways. One would be to set the value as a HttpServletRequest attribute with key as "key" and then retrieve it on the next page using request.getAttribute("key"). Another way would be to use sessions to persist user data.
Since you are using JSF things should be pretty easy. Just use your backing bean methods to retrieve the desired value from the current page, set it in session, let the navigation handler decide which page to next go to using the return value of the backing bean method and in the backing bean of that page retrieve the session stored value and then remove it from the session.
All the above has been explained assuming you know JSF, if you don't it's about time you started reading some good books. Actually, what you ask for here encompasses the complete technical architecture of your application, so it's kind of hard to explain it. Good books / tutorials and trial and error are your way to go.