Article I , Section 5, Clause 2
That would be a tough sell. Nearly every member of Congress that's been expelled was kicked out because they sided with the Confederacy during the Civil War. Only a tiny handful of members have been expelled since then. They did manage to expel Jim Trafficant in 2002, though.
Personally, I would introduce a bill to expunge the censure of Paul Gosar from the congressional record. They could easily pass that along party lines, and there IS precedent to expunge a Censure. That would make Schiff the first member Censured since Charles B. Rangel in 2010 (and before that, Gerry Studds in '83... Bob Dornan, Newt and Joe Wilson received congressional "reprimands" but that is considered "less harsh" than a Censure, and is not read aloud into the Congessional record while the member stands before the House and gets rebuked by them)