Layer-by-Layer 코팅법 기반 수처리막 제조 및 나노여과 분리막의 특성 평가

초록

Global water scarcity has intensified interest in organic solvent nanofiltration (OSN) technologies that purify and recycle spent organic solvents. In this study, we fabricated thin-film membranes via a facile layer-by-layer (LBL) coating technique—renowned for its precise thickness control—and evaluated their nanofiltration performance. A polyacrylonitrile (PAN) support was prepared by non-solvent induced phase separation (NIPS) using a 19 wt% PAN solution. Sequential deposition of a chitosan cationic layer and three anionic layers [polyacrylic acid (PAA), graphene oxide (GO), and a PAA–GO blend] yielded a range of LBL membranes. Notably, the chitosan/PAA three-layer membrane (PAN(CS/PAA)3) achieved a pure water permeability of 9.25 LMH/bar, NaCl and MgSO4 rejection rates of 33.77% and 78.43%, and Congo red and methyl orange removal efficiencies of 95.5% and 77.79%, respectively. These results demonstrate that LBL coating enables fine-tuning of membrane chemistry and structure to achieve both high permeation and selectivity, confirming their practical applicability in OSN and water treatment.

키워드