The removal of n-butanol (BuOH) from 2,5-dimethylfuran (2,5-DMF) is an important issue in the sustainable production of 2,5-DMF from fructose in biphasic organic solvents such as BuOH. The formation of an azeotrope (at 90 mol % 2,5-DMF) renders conventional distillation ineffective for producing pure 2,5-DMF. Here we describe a highly butanol-selective adsorption process based upon zirconium terephthalate (UiO-66) metal organic frameworks. In particular, defects created by monoacid modulators lead to increased surface polarity and pore volume, leading to enhanced butanol selectivity and capacity. The adsorption behavior of 2,5-DMF and BuOH in pristine (nonmodulated), benzoic acid-modulated (BA) and formic acid-modulated (FA) UiO-66 MOFs, as well as the structural and textural characteristics of these materials, are investigated in detail via a suite of characterization methods. Unary adsorption isotherms show a tunable increase in the BuOH adsorption selectivity in the order UiO-66 < BA-UiO-66 < FA-UiO-66...