Transfer Terminal 2 to Terminal 3 in Beijing Airport

Dear All,
Im arriving from Pyongyang (Terminal 2) and have to get a flight in Terminal 3 around 2,5h later.

1. Will the time be enough? I think it will get pretty close.
2. How is the process with the luggage and so on? Can I stay somehow in the transit zone to avoid checking in and out again? Since the luggage wont be forwarded automatically.

Thank you very much in advance