The formation of the inclusion complexes between two phenylethanol isomers [1‐phenylethanol (1‐PE) and 2‐PE)] and three cyclodextrins namely α‐cyclodextrin (α‐CD), β‐cyclodextrin (β‐CD) and HP‐β‐cyclodextrin (HP‐β‐CD) was studied. Phase‐solubility studies showed the two isomers formed 1:1 stoichiometric inclusion complexes with these cyclodextrins and the aqueous solubility of 1‐PE and 2‐PE significantly increased with increasing the cyclodextrin concentration. In this study, β‐CD was chosen as a host molecule, and solid inclusion complexes of β‐CD with two phenylethanol isomers were prepared via the co‐precipitation method for the enhancement of their thermal stability and sustained release. The presence of the two isomers in the inclusion complexes was confirmed by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H‐NMR) spectra. X‐ray powder diffraction (XRD) results indicated new crystalline phases for the inclusion complexes. Differential scanning calorimetry (DSC) studies for the inclusion complexes have also shown the formation of supramolecular inclusion complexes between β‐CD and the two isomers. Thermogravimetric analysis (TGA) results demonstrated that the thermal stability of the two isomers was increased as a result of the formation of the inclusion complexation with β‐CD. The release study suggested that β‐CD provided protection for 1‐PE and 2‐PE against evaporation, and 1‐PE in the inclusion complex had a lower release rate than that of 2‐PE. The results have been confirmed with PM3 and B3LYP/6‐31G(d) calculation. It indicates that β‐CD is a proper wall material for increasing thermal stability and the controlled release of 1‐PE and 2‐PE. Copyright © 2015 John Wiley & Sons, Ltd.

A hyper-crosslinked resin chemically modified with thiourea (TM-HPS) was synthesized, characterized, and evaluated for the removal of heavy metal ions (Pb 21 , Cd 21 , and Cu 21 ) from aqueous solutions. The structural characterization results showed that a few thiourea groups were grafted on the surface of the resin with a big BET surface area and a large number of narrow micropores.Various experimental conditions such as pH, contact time, temperature, and initial metal concentration of the three heavy metal ions onto TM-HPS were investigated systematically. The results indicated that the prepared resin was effective for the removal of the heavy metal ions from aqueous solutions. The isotherm data could be better fitted by Langmuir model, yielding maximum adsorption capacities of 689.65, 432.90, and 290.69 mg/g for Pd 21 , Cd 21 , and Cu 21 , respectively. And the adsorption kinetics of the three metal ions followed the pseudo-second-order equation. FTIR and XPS analysis of TM-HPS before and after adsorption further revealed that the adsorption mechanism could be a synergistic effect between functional groups and metal ions and electrostatic attraction, which may provide a new insight into the design of highly effective adsorbents and their potential technological applications for the removal of heavy metal ions from aqueous solutions.

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