The world's biggest iron ore producer Rio Tinto will raise $9 billion in U.S. investment-grade bonds as it seeks to fund its recently-closed buyout of Arcadium Lithium, the miner said on Wednesday. Rio is offering the fixed and floating rate debt in eight tranches with terms varying from two years to 40 years.

Rio Tinto (NYSE:RIO) sold $9B of U.S. investment-grade bonds, as the miner raised funds for its recently-closed buyout of Arcadium Lithium, Bloomberg reported Tuesday. The debt was sold in eight parts,

Rio Tinto Group said it’s seeking to sell bonds in the US to help repay a bridging loan used to finance its $6.7 billion acquisition of Arcadium Lithium Plc.