In order to remove fluoride ions from aqueous solution, PVC-Al(OH)3 beads were prepared by immobilizing Al(OH)3 with polyvinyl chloride (PVC). The prepared PVC-Al(OH)3 bead was characterized by using SEM, EDS and Zeta potential. Dependences of pH, contact time and initial fluoride concentration on the adsorption of fluoride ions were studied. The optimal pH was in the range of 4～10. The adsorption was rapid during the initial 12 hr, and equilibrium was attained within 72 hr. The adsorption rate of fluoride ions by PVC-Al(OH)3 beads obeyed the pseudo-second-order kinetic model. The maximum adsorption capacity obtained from Langmuir isotherm model was found to be 62.68 mg/g.

The solid phase extractant (PVC-D2EHPA bead) was prepared by immobilizing di-2-ethylhexyl-phosphoric acid (D2EHPA) with polyvinyl chloride (PVC). The prepared PVC-D2EHPA beads were characterized by using fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The removal experiments of Cu(II) by PVC-D2EHPA beads conducted batchwise. The removal kinetics of Cu(II) was found to follow the pseudo-second-order model. The equilibrium data fitted well with Langmuir isotherm model and the maximum removal capacity was 2.6 mg/g at 20℃. The optimum pH region was in the range of 3.5 to 6. and the standard free energy (△G o ) was between -4.67 ∼-4.98 kJ/mol, indicating the spontaneous nature of Cu(II) removal by PVC-D2EHPA beads.

The adsorption characteristics of the methylene blue (MB) were studied using three activated carbons such as ACA and ACB with similar specific surface area (1,185 and 1,105 m 2 /g), and ACC with relatively high specific surface area (1,760 m 2 /g). The surface chemical properties of these activated carbons were investigated by X-ray photoelectron spectroscopy (XPS). The results indicated that ACA had more functional groups (with phenol, carbonyl, and carboxyl etc.) than ACB (with carbonyl and carboxyl) and ACC (with carboxyl). The isotherm data were fitted well by Langmuir isotherm model. The adsorption capacities of ACA, ACB, and ACC for MB were 454.7 mg/g, 337.7 mg/g, and 414.0 mg/g, respectively. As phenol and carboxyl content of the surface on activated carbon increased, MB adsorption capacity was increased. Although ACA had a smaller specific surface area than ACC, the content of phenol and carboxyl group was abundant, so MB adsorption capacity was found to be higher than ACC.