Yes, you can. All the information you need, plus a link to the online reservation form, can be found at this page.
The library also has a few 'first come, first served' rooms on the third and fourth floor: 3001, 3002, 4003, 4010, 4011, and 4013.
However, all group study rooms for designed for group use, so if you are sitting alone in an open room and a group asks to use it, please relinquish the space, and find other seating in the Library.