In this study, pitch crosslinked by oxygen function groups was made into activated carbon (AC) and pore structure was observed. The oxygen functional groups were introduced by the addition of waste PET for pitch synthesis. Activation agent ratios used to obtain the AC during the activation process were 1:1, 1:2 and 1:4 (pitch:KOH, w/w). The oxygen content in the prepared pitch was characterized by elemental analysis. Also, the molecular weight of pitch was investigated by MALDITOF. Specific surface area and micropore volume of the prepared AC were determined by the argon adsorption–desorption analysis and calculated using the Brunauer–Emmett–Teller and Horvath–Kawazoe equations, respectively. Micropore fraction of PET-free AC was smaller than that of PET-added AC. At high activation agent ratio, mesopores were created when the micropore structure collapsed. However, in the PET-added AC, due to the oxygen crosslinking effect, the micropore structure and micropore size were maintained even at a high activation agent ratio. Therefore, PET AC was found to have a higher micropore fraction than that of PET-free AC.

Membrane-based CO2 capture is an energy-saving way to separate CO2 from N2 in post-combustion. Chabazite (Si-CHA) zeolites with a pore size of 0.37 nm × 0.42 nm are expected to separate CO2 from larger N2 (0.364 nm) by recognizing minute size differences. The pore mouth size on the Si-CHA zeolites outer surface was reduced via the chemical vapor deposition (CVD) to increase the molecular sieving effect by disfavoring the penetration of N2. The CVD process was conducted on CHA membranes to improve their CO2/N2 separation performance. Compared to the intact CHA membranes, the CO2/N2 max separation factor for CVD-treated CHA membranes increased by ~2.5 fold under dry conditions and by ~6.4 fold under wet conditions. It is noteworthy that the membrane kept its separation performance without degradation in the presence of H2O.

하전된 마이크로채널의 전기이중층에서 계면동전기 흐름에 의해 발생되는 흐름전위는 일반적 Helmholtz-Smoluchowski 관계식으로부터 중공사 멤브레인 기공의 제타전위를 결정하는데 적용된다. 흐름전위는 실제 운전상황이나 물리화학적 조건에서의 표면특성 및 기공과 입자간 상호작용에 대한 유용한 실시간 정보를 제공함이 알려져 있다. 무리화학적 인자들이 주공사에 의한 여과에 미치는 영향을 투과플럭스와 흐름전위의 동시적 모니터링으로 고찰하였다. 특히, 본 연구에서는 중공사의 위치에 따른 흐름전위를 측정함으로써 중공사 길이 방향과 멤부레인 오염 진행에 따라 달라지는 케이크층 효과를 규명하는 실험방법을 다루었다. 실험결과, 입자농도가 증가할수록 투과플럭스는 감소하나 흐름전위는 증가하였다. 입자농도가 증가하면서 케이크층 성장은 활발하지만 쌓인 하전 입자들의 표면전하 효과로 흐름전위는 증가한 것이다. 용액의 이온화 세기를 KCI 0.1 mM에서 10mM로 증가하면 투과플럭스와 흐름전위가 함께 감소하였다. 이는, 이온화 세기의 증가로 라텍스입자 주위의 Debye 길이 감소로 치밀한 케이크층이 형성되고, 전기이중층의 얇아진 확산층에 의한 이온흐름의 약화로 흐름전위는 감소한 것을 판단된다.