본 연구에서는 다공성 Polyacrylonitrile (PAN) 중공사막을 지지체막으로 하여 Poly styrene sulfonic acid (PSSA) 와 polyethyleneimine (PEI)을 이용하여 layer-by-layer법으로 선택층을 형성시켰다. 코팅용액에 Mg염을 첨가하여 염석법(salting out method)을 이용하였다. 코팅용액의 이온세기, 고분자 농도, 코팅시간 등을 달리하여 나노여과막을 제조하였으며 NaCl, MgCl2, CaSO4 100 mg/L를 공급액으로 하여 2 atm의 구동 압력에서 투과도와 염 배제율을 평가하였다. PSSA 20,000 ppm, 코팅시간 3분, 이온세기 1.0, PEI 30,000 ppm, 코팅시간 1분, 이온세기 0.1의 조건으로 코팅한 막이 가장 우수한 성능을 보여 주었다. 100 ppm의 NaCl, MgCl2, CaSO4 공급액에서 각각 20.4, 19.4, 18.7 LMH의 투과도와 67, 90, 66.6%의 염 배제율을 나타내었다.

본 연구에서는 다공성 PAN(Polyacrylonitrile) 중공사 분리막을 지지체로 이용하여 계면중합반응을 통해 나노여과막을 제조하였다. 지지체로는 PAN을 사용하였으며 수용상으로는 피페라진으로 중공사 분리막 내부에 코팅한 후 유기상인 TMC와 반응하여 계면중합이 일어나도록 진행하였다. 지지체로 사용된 UF 중공사 분리막은 분획분자량 10,000, 30,000, 100,000Da를 각각 사용하였으며 피페라진(Piperazine) 농도를 0.1%, 02%, 0.3%, TMC(Trimesoyl Chloride)의 농도를 0.05%, 0.1%, 0.2%로 변화시켜 제조 하여 5bar에서의 수투과도(LMH)와 MgSO4 2000ppm, Na2SO4 2000ppm, NaCl 500ppm 수용액으로부터 염배제율(Rejection, %)을 확인하였다.

In this study, the oxyfluorination of PAN-based carbon fibers was undertaken at room temperature using fluorine-oxygen mixtures, and the influence of oxyfluorination on properties was investigated. The surface characteristics of the modified fiber were determined by using X-ray photoelectron spectroscopy (XPS) and dynamic contact angle analyzer. The oxyfluorination of carbon fibers was one of the more effective methods to increase surface wettability by the formation of semicovalent C-F bond and C-O bond depending on reaction conditions. When oxygen mole fraction is increased from 0.5 to 0.9, it is probable that attached fluorine atoms at the surface of the fibers reacted with other components. As increased oxyfluorination time and decreased its pressures, semi-covalent peak is increased at 0.5 of oxygen mole fraction. The total surface free energy of oxyfluorinated carbon fibers decreased with increasing oxygen mole fraction over 0.5. These results indicate that the surface of carbon fibers became much more hydrophilic after the short oxyfluorination. The surface free energy of oxyfluorinated carbon fibers progressively decreased after 10 min treatment. The polar components of surface free energies were however, significantly higher for all oxyfluorinated samples than that for the untreated carbon fiber.

Zeolite (FZ), prepared from fly ash, was immobilized with polyacrylonitrile (PAN) to fabricate PAN/FZ beads. The prepared PAN/FZ beads were characterized by scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The optimum ratio to prepare PAN/FZ beads was 0.3 g of PAN to 0.3 g of FZ. The diameter of the prepared PAN/FZ beads was about 3 mm. Sr and Cu ion adsorption experiments were conducted with PAN/FZ beads. A pseudo-second-order model fit the kinetic data for Sr and Cu ion adsorption by PAN/FZ beads well. The equilibrium data fitted well with the Langmuir isotherm model, and the maximum adsorption capacities were 96.5 mg/g and 74.6 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as Gibbs free energy (ΔGo), enthalpy (ΔHo) and entropy (ΔSo) were determined. The positive values of ΔHo revealed the endothermic nature of the adsorption process and the negative values of ΔGo were indicative of the spontaneity of the adsorption process.