A high efficiency and rapid adsorbent for removing sunset yellow FCF by amine-modified microporous polymer

A high specific surface area amine-modified polymer of intrinsic microporosity (NH 2 -PIM-1) was synthesized by reducing nitriles to amines in the polymer of intrinsic microporosity (PIM-1) as an adsorbent to remove sunset yellow FCF (SY) from aqueous solution. The physicochemical properties of NH 2 -PIM-1 were characterized by infrared spectra (IR), scanning electron microscope (SEM), thermogravimetric analysis (TGA), nuclear magnetic resonance (NMR) and N 2 adsorption-desorption isotherms measurement. The effect of initial solution pH value, dosage of adsorbent, contact time and initial SY concentration were systematically investigated. The sunset yellow FCF adsorption equilibrium was attained after 10 min and the adsorption capacity could reach 348.16 mg/g, which was superior to most of the other adsorbents previously reported. Kinetics and isothermal model experiments indicated that the adsorption of sunset yellow matched the pseudo-second-order kinetic model and Langmuir model, respectively. Thermodynamic analysis showed that the adsorption was endothermic, spontaneous and physical adsorption process. These results suggested that the NH 2 -PIM-1 was a rapid and efficient kind of adsorbent for removal of sunset yellow FCF.