Traveling in January from Hangzhou to Maputo,my connecting flight is in Beijing both Air China.

According to your situation, it is a domestic to international transfer at PEK. Both airlines are located in T3. The detailed transfer procedures are the following:
1:Flight Arrival & Transfer Procedures
2:Inspection & Quarantine
3:Exit and Entry Frontier Inspection
4:Security Check
5:Customs inspection
6:Waiting & Boarding
You don't need to collect the luggage and recheck them. But generally speaking, the 2 hour's transfer time is tight. You need to complete the mentioned transfer procedures ASAP.

Thank you so much Austin,I’m really worried about the time as well because my connecting flight leaves at 12:10am midnight