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.

To develop the protein materials by the reutilization of dead flatfish from fish farms in Jeju island, the physicochemical characteristics and the functional activities of collagen peptide extracts were investigated. Flatfish skin collagen peptide (FSCP) and flatfish protein hydrolysate (FPH) were manufactured from dead flatfish. The differences of pH, moisture and fat contents between FSCP and FPH were not significant, fat contents were analyzed less than 0.3%, and trans-fat, saturated fat and cholesterol were not detected in both samples. Protein contents of FSCP and FPH showed about 92% and 95%, respectively. In the analysis of amino acids, glycine and hydroxy proline content in FSCP was 24.22% and 6.15%, respectively, showed a typical characteristics of the collagen protein, but essential amino acids contents such as threonine, valine, methionine, isoleusine, leusine and phenylalanine were relatively higher than those of FPH. Average molecular weight of FSCP was measured as 1,102 which was almost equal value with that of tuna collagen peptide. The antioxidant activities and functional properties showed high but did not show significant difference between two samples.

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.

In this study, the photocatalytic decomposition characteristics of single toluene, toluene mixed with benzene, toluene mixed with acetone, and toluene mixed methyl mercaptan (MM) by UV reactor installed with TiO2-coated perforated plate were studied. The photocatalytic decomposition rate of single toluene, toluene mixed with benzene, toluene mixed with acetone, and toluene mixed with MM fitted well on Langmuir-Hinshelwood (L-H) kinetics equation. The maximum elimination capacity was obtained to be 628 g/m ·d for toluene mixed with MM, respectively. The negative effect in photocatalytic decomposition of toluene are found to be in the order of acetone>benzene>MM.