Dual-activation interfacial polymerization based anionic covalent organic framework nanofiltration membrane for high-flux dye separation

•Synthesis of a robust and highly crystalline anionic COF membrane.•The TpPa-SO3Na membrane is suitable for filtration of various organic solvents.•The TpPa-SO3Na membrane exhibits ultrahigh water permeability.•The TpPa-SO3Na membrane shows excellent rejection rate of positively charged dyes.•The TpPa-SO3Na membrane can selectively separate different dye molecules.