suggest a method to seperate O2 to from air (b.pt of O2=90K ,b.pt of N2=77K)

Oxygen can be seperated from air by fractional distillation.Pressure is increased and temperature of air is lowered.When water vapour and liquid air is cooled down at high pressure, liquid seperates and only pure oxygen remains and for seperating nitrogen from oxygen , we need to lower done the temperature of air mixture at -182.95 degrees, at this temperature, oxygen turns liquid while nitrogen will remain a gas and can be easily seperated.