The present invention relates to a method for supplying oxygen to a water purification process, said method comprising providing an oxygen carrier of at least one copolymer of dimethylsiloxane, ethylene oxide and propylene oxide, adding said oxygen carrier to the water purifying process, and contacting said oxygen carrier with an oxygen containing gas. The invention further relates to the use of at least one copolymer of dimethylsiloxane, ethylene oxide and propylene oxide, as an oxygen carrier in a water purification process.