2 hours transfer time at T3, Mongolian airlines to Lufthansa, is this enough?

Hello, on 17th June I will be arriving from Mongolia to Beijing (T3), scheduled arrival 8.25am, then I need to check in with Lufthansa and board a plane that leaves 10.30am. I will have exactly 2 hours if the plane arrives on time? Is this enough? (I will buy both tickets separately..so I assume I will need to leave the transit area, go to the departure hall, then security etc.). is this too tight? Can you tell me what exactly will be the procedures I will need to go through upon arrival? (I will have no check-in luggage, only a small bag with me). Thank you.