Which process is used to separate the ortho-nitrophenol and meta-nitrophenol?

Steam distillation Fractional distillation Zone distillation vaccum distillation

Steam distillation

The ortho and para isomers can be separated by steam distillation. o-Nitrophenol is steam volatile due to intramolecular hydrogen bonding while p-nitrophenol is less volatile due to intermolecular hydrogen bonding which causes the association of molecules.