Synthesis and characterisation of sodium trititanate whisker surface Cd(ll) ion-imprinted polymer and selective solid-phase extraction of cadmium

摘要

A new surface ion-imprinted polymer (IIP) was synthesised with sodium trititanate whisker in the presence of Cd(II), chitosan (CTS) and γ-glycidoxypropyl trimethoxysilane (KH-560). The prepared surface IIP was characterised by using FTIR, UV, XRD and SEM. A batch of adsorption experiments were performed to evaluate the adsorption behaviour of Cd(II) using inductively coupled plasma atomic emission spectrometry (ICP-AES). The effects of solution pH and sorbent amount on the extraction of Cd(II) from aqueous solutions were studied. The adsorption kinetics and adsorption isotherm were also obtained. The Langmuir isotherm can fit the experimental equilibrium data. Under the optimum conditions, the value of the adsorption was above 99%, and the maximum adsorption capacity was 52.34 mg/g. In accordance with the parameters distribution coefficient (K_d) and selectivity coefficient (K), the selectivity for Cd (II) of the prepared imprinted polymer was higher than non-imprinted polymer. Finally, the reuse of imprinted sorbent was discussed and showed that it could be reused nine times with about 5.0%-6.0% regeneration loss. The detection limit of 0.024 μg·mL~(-1) with the relative standard deviation (RSD) of 1.74% (C = 1.0 μg·mL~(-1), n = 13) of this method was obtained.