Polyamide (PA) thin-film composite (TFC) membranes consisting of m-phenylenediamine (MPD) and trimesoylchloride (TMC)　monomers have been widely used in desalination process for decades. Still, a rational design of PA TFC membranes by tailoring monomer species and concentration could further reduce the energy consumption in desalination process. In this study, we prepared PA TFC membranes using mixed amine monomer depends on the number of -NH₂group and investigated the desalination performance of prepared membranes. The crosslinking between amine and acyl chloride group was confirmed by infrared spectroscopy regardless of amine species. Surface morphologies which were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed increased surface roughness.

20 μm의 얇은 폴리에스터(polyester) 부직포 상에 폴리술(polysulfone) 고분자 지지체를 제조하였다. 폴리술폰 표면에 3-aminopropyldimethyl silane을 sol-gel 중합함으로써 폴리실록산 지지체를 제조한 후 MPD 수용액과 TMC 유 기용액의 계면 중합을 실시를 통하여 정삼투 복합박막을 얻었다. FE-SEM/EDX 분석을 통하여 폴리실록산이 표면에 한하여 분포됨을 확인하였다. 1 M NaCl 유도용액/순수 인입용액 하에서의 FO-mode 유량이 146 - 209 LMH로 향상되 었으며 RSF값은 0.42 - 16.3 GMH로 유지함을 확인할 수 있었다.

Owing to high energy efficiency and superior efficacy, membrane-based desalination processes have gained widespread implementation in a wide variety of water treatment applications. Tremendous research efforts on new membrane materials have been made to improve the separation performance of the state-of-the-art thin-film composite (TFC) membranes, particularly polyamide TFC membranes, hoping to overcome the permeability-selectivity trade-off relations. Currently, many nanomaterials such as zeolites, metal-organic frameworks (MOFs), graphene oxide (GO), and carbon nanotubes (CNTs) have been explored to enhance the separation performance of existing polymeric membranes, but it has been argued that the positive transformation of nanomaterials-embedded TFC membranes hold promising potential to realize the sustainable development of current desalination membranes. Here we have tried to discuss some misconceptions and challenging items delaying industrial-scale implementation of nanomaterialsembedded desalination membranes.

We report on a unique fabrication technique, DSC for high performance PA TFC RO membranes. DSC allows the simultaneous and continuous spreading of two reactive monomer solutions to create an unsupported PA layer, which is then adhered onto a porous support to form a membrane. DSC facilitates the characterization of the PA layer structure by easily isolating it. The DSC-PA layer exhibits a thinner and smoother structure with a more wettable and less negatively charged surface than one prepared via conventional interfacial polymerization (IP). DSC enables the formation of an extremely thin (~9 nm) and dense PA layer using a very low MPD concentration, which is not feasible by conventional IP. Importantly, the DSC-assembled membrane shows the excellent water flux and NaCl rejection, exceeding both the IP control and commercial RO membranes.

Flat sheet membranes consisting of a selective layer and a porous support usually require gutter layer to reduce the bulk pores of the substrates. The gutter layer mitigates the geometric restrictions of support, which enables selective layer to have defect-free morphology with thin thickness (< 100 nm). For this reason, the gutter layer has been introduced to many industrial membranes, and the systematical studies of the effects of the gutter layer properties on membrane performance should be needed. Herein, we introduced several gutter layers with different thicknesses into graphene oxide intercalated polymer TFC membranes to determine the relationship between gutter layer properties and total membrane performances. This study provides more practical insight to determine the optimum gutter layer properties in designing TFC membranes.

20 μm의 얇은 폴리에스터(polyester) 부직포 상에 폴리술폰(polysulfone) 고분자 지지체를 제조하였다. 폴리아미드 계면 중합이 일어날 폴리술폰 표면에 폴리 실록산 층이 형성될 수 있도록 실란 화합물을 중합하여 폴리실록산 지지체를 제조하였다. 얻어진 복합막 지지층에서 MPD 수용액과 TMC 유기용액을 계면 중합을 실시한 결과 정삼투 분리용 복합박막을 얻을 수 있었다. FE-SEM을 이용하여 지지층의 구조가 sponge-like 구조임을, EDX를 통하여 폴리실록산이 표면에 한하여 분포됨을 확인하였으며 1 M NaCl 유도용액하에서의 FO-mode 유량 이 79.2 - 117 LMH로 향상되었으며 RSF값은 2.12 - 7.97 GMH로 유지함을 확인할 수 있었다.

제련공정 산업에서 발생하는 희소/유가 금속을 함유한 산 폐수는 금속의 산세정 과정에서 다량 방출된다. 주로 중화나 치환법, 이온교환법 등을 사용하였지만 큰 비용과 친환경적이지 못한 단점이 있다. 이에 본 연구에서는 제련 공정에서 발생하는 희소금속을 함유한 폐산용액을 막분리법을 적용하여 분리하기 위해 내산성이 향상된 thin-film composite NF membranes (TFC-NF)을 제조하고자 하였다. TFC-NF는 다공성 지지막 위에 polyamide 계면중합법을 이용하여 제조하였다. 제조 한 TFC-NF는 15 wt% 황산에 노출한 후, 75psi 압력의 cross-flow 방식으로 내산성 투과실험을 진행하였고 ATR-FTIR, XPS, FE-SEM 등을 통해 막의 특징을 분석하였다.