Preparation of a thermosensitive surface imprinted polymer based on palygorskite for removal of copper (II) from environment aqueous solution

Abstract

ABSTRACT In this study, a new thermosensitive surface imprinted polymer based on palygorskite was successfully synthesised by a surface imprinting technique and used as an intelligent selective recognition adsorbent for the adsorption of Cu(II) ions from aqueous solution. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) measurements results demonstrated that Cu(II)-imprinted polymer was successfully synthesised. The separation and preconcentration characteristics of Cu(II)-imprinted polymer for Cu(II) were researched by batch and column procedures. optimal intelligent recognition temperature for adsorption is 35°C and intelligent identification and elution of Cu(II) can be achieved by adjusting the temperature. The maximum static adsorption capacity of the ion-imprinted and non-imprinted sorbents for Cu(II) was 35.55 and 9.78 mg g−1, respectively. The relative selectivity factor values (ar) of Cu(II)/Zn(II), Cu(II)/Ni(II), Cu(II)/Co(II) and Cu(II)/Pb(II) were 111.48, 85.37, 98.31 and 73.85 respectively, which were all greater than 1. The Cu(II)-imprinted polymer offered fast kinetics for the adsorption and desorption of Cu(II). Under the optimised conditions (pH-5, temperature-35°C, shaking time-15 min), a detection limit of 0.21 μg L−1 with a relative standard deviation (RSD) of 2.5% for Cu(II) was obtained. Based on Cu(II)-imprinted polymer packed columns, a highly selective pre-concentration method for Cu(II) was established. The accuracy of the method has been certified using national reference materials (GBW 08301). This method has also been successfully used for the determination of Cu (II) in locally collected water samples.