By Clara Denina
LONDON, March 16 (Reuters) - Rio Tinto RIO.AX RIO.L has asked Swiss investment bank UBS UBSAG.UL to explore a possible public listing of its Pacific Aluminium smelting business on the Australian Stock Exchange (ASX), two industry sources said on Friday.
The mining group has tried to sell the division many times without success, including in 2017, when it added two alumina refineries in Australia to the portfolio to make it more appealing, the sources said.
The addition of QAL and Yarwun alumina refineries, however, doubled the $1 billion price tag and interest waned, they added.
"Rio Tinto wasn't satisfied with the level of the offers, so they decided to appoint UBS to try and do an IPO," one of the sources said.
"There were three bidders left at the end of the process: U.S. producer Century Aluminium CENX.O , private equity firm Apollo Management and Britan's Liberty House," the source added.
The sources declined to be named because they are not authorised to speak to the press.
Rio had mandated Deutsche Bank DBKGn.DE to help with the sale process.
Rio Tinto declined to comment and UBS was not immediately available to comment.
Pacific Aluminium originally included Rio Tinto's Bell Bay, Boyne Island and Tomago smelters in Australia, and the Tiwai Point smelter in New Zealand.
Rio inherited the assets as part of its $38 billion acquisition of Canadian aluminum maker Alcan Inc.
Aluminium prices rose 34 percent in 2017 as China, the world's biggest producer, cut output to fight pollution.
Chief executive Jean-Sebastien Jacques, who took over in July 2016, is seeking to divest all but Rio Tinto's best-performing units.
Rio sold its Coal & Allied thermal coal division in 2017 for $2.7 billion and it is also in the process of selling two Australian coking coal mines.