We would like to close the tickets from a particular email address after two hours of creation.

Below are the things we have to do if the ticket come from particular email address :

      1) change field name 

      2) close ticket after two hours

For the first step, we wrote a workflow rule and its working fine. Can you please tell us how can we implement the second one?

Note : No need to assign the tickets to anyone. We have to just close it after two hours. 

Thanks 

Samir