Of all the reasons to split up a party, the players arguing might actually be a good one. Sequester them in different rooms and pop between them, GMing each in turn.
Try designating part of each room as the "naughty corner" and insisting the recalcitrant players sit there until they can cooperate again.
If your players have an emotional maturity at least as developed as pre-schoolers, it might just work. Oh, wait...
R2-D2: Sand. Why did it have to be... sand?
C-3PO: There's a settlement this way.
R2-D2: Yeah but my tracker says my dreadnought is that way.
C-3PO: It's been here for 19 years. Do you really think it'll be in working order?
R2-D2: Head that way if you like. I'll pick you up before you even get there.
C-3PO: We're four sessions into a new adventure, Jim's had four characters killed, Princess has been captured, and now you want us to split up?
R2-D2: It's not my fault if Obi-Wan was too stupid to remember to return my dreadnought.
C-3PO: Don't you talk about my brother like that!
R2-D2: Whoa... calm down.
C-3PO: You never really liked him! What, are you glad he's gone?!
R2-D2: No! I never—
C-3PO: You go that way! Find your stupid dreadnought!
GM: Uh... maybe we can stop here for tonight.
C-3PO: No! We keep playing! Ben would have wanted it that way.