(Bloomberg) -- United Airlines presents itself as the unrivaled leader in cleaner jet fuel. A recent ad campaign featuring the garbage-can-dwelling Oscar the Grouch as the airline’s new “chief trash officer” publicizes its commitment to turn banana peels and old socks into less-polluting jet fuel. In another ad, the company says it’s “investing in more sustainable aviation fuel production than any other airline in the world.”Most Read from BloombergAston Martin Owner Lawrence Stroll Sells F1 Tea