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4-Nitrophenol is a highly toxic environmental pollutant. It is a challenge to selectively remove it from a mixture of various pollutants. Herein, we report a study on the selective adsorption of 4-nitrophenol by using molecularly imprinted polymers (MIPs). The imprinted polymer was synthesized using cellulose as a framework, onto which, the complex of the imprinting molecule (i.e., 4-nitrophenol) and a candidate material [namely, 2-(dimethylamino)ethyl methacrylate. DMAEMA] was grafted. The obtained MIP showed an excellent adsorption capacity with good selectivity. Also, the adsorption of 4-nitrophenol by the obtained MIP was fast and the adsorbent exhibited good recyclability. The thermodynamics and kinetics of the adsorption process of 4-nitrophenol by MIP was thoroughly studied, where an otherwise-equivalent non-imprinted polymer was used as a control in the experiments. The selectivity of the MIP adsorbent for 4-niteophenol was evaluated by two types of experiments: (1) adsorption experiments in single-component adsorbate systems (containing 4-nitrophenol, 3-nitrophenol, catechol, or hydroquinone), and (2) competitive adsorption experiments in binary adsorbate systems (containing 4-nitrophenol plus either 3-nitrophenol, catechol or hydroquinone). The selectivity coefficient for 4-nitrophenols was twice of those of other phenols (that were all around 2), indicative of the extent of the affinity of MIPs to these phenolic compounds. The recyclability of the adsorbent was evaluated for 5 adsorption–desorption cycles, where the adsorption capacity of the last cycle remained over 90.2% of that of the first cycle. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, we report a study of the design and synthesis of a bifunctional cellulose derivative on the removal of phenols and heavy-metal ions in wastewater treatment. A radical polymerization was performed in an ionic liquid, 1-allyl-3-methylimidazolium chloride, to graft two monomers, butyl methacrylate and 4-vinyl pyridine, on the backbone of cellulose. The effects of the five reaction conditions on the yield of final products were evaluated. The grafted celluloses were characterized by means of Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. Adsorption experiments were carried out on the cellulose- g-poly(butyl methacrylate- co-4-vinyl pyridine) to evaluate the capacity of the removal of 2,4-dichlorophenol (2,4-DCP) and Cu(II) in water. The adsorption isotherms were measured at five temperatures and interpreted by a Langmuir model of adsorption. The thermodynamics of the adsorption suggested that the binding process was mildly exothermic for Cu(II) and endothermic for 2,4-DCP. Kinetic studies were interpreted with a pseudo-second-order adsorption model. The process of the adsorption of 2,4-DCP could be described overall by the model, whereas the adsorption of Cu(II) involved two processes. This was due to adsorption both on the surface and inside the adsorbent. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41830. [ABSTRACT FROM AUTHOR]