How to work effectively with unengaging labmates as a graduate student?
From your question, I get that you feel like the big fish in the small pond. It does happen, but you might be able improve your situation and your environment. Here's a few ideas:


If your lab doesn't do it, propose weekly lab meetings or a journal club where science is discussed. Yes, it means more work for you, especially if no one else is interested in leading some of those meetings. But it will bring some science discussion to the group, and might excite their curiosity.
Seek scientific fulfillment in other groups: open the journal club to other related labs at your university, or join a professional organization linked to your discipline. There's plenty of opportunity for grad students to get involved.
Twitter is full of grad students like you. You will find that you can engage in science conversations and get support from fellow graduate students. 


In any case, you have a great opportunity to act as a leader in your group. In the best case scenario, your example will motivate the other students and you will create a better environment. If not, your involvement will be noticed and it will be good for your own career.