Separation Science and Technology, Vol.41, No.15, 3409-3430, 2006
Selective solubilization of nitrophenols and adsorption on ion exchange resins in nonaqueous conditions
Separation of nitrophenols (NP) has been studied by selective solubilization in organic solvents of different polarities. o-NP dissolves very well in heptane and toluene while intermolecular hydrogen bonding among p-NP molecules decreases its solubilization in these solvents. Thus partial separation of o-/p-nitrophenols is achieved by selective solubilization of o-NP in heptane. The trace amounts of p-NP from the o-NP solutions are removed by its selective sorption on basic ion exchange resins. The sorption of nitrophenols, individually and in mixtures, is experimentally determined from their solutions in heptane, toluene, and methanol by using weakly basic Indion-850 and Duolite A-308 resins and strongly basic Indion-810 resin. The equilibrium adsorption studies show very selective adsorption of p-NP from heptane with a high loading capacity on Indion-850.