Found this: Billy Coutu was the first, and to date only, player banned from the NHL for life for violence in 1927; he assaulted referee Jerry Laflamme and tackled referee Billy Bell before starting a bench-clearing brawl during a Stanley Cup game between the Boston Bruins and Ottawa Senators. The penalty was commuted after two-and-a-half years, but Coutu never played in the NHL again.
Raffi Torres was suspended 41 games in 2015 (the same number of games Shane Pinto was suspended for gambling issues). Torres was for an illegal check to the head on Jakob Silfverberg and interference (longest non-lifetime suspension in NHL history; suspension length was issued because Torres had nine previous instances of NHL rule violations which required supplemental discipline rather than the check itself)