Synthesis of 4-Aminobenzoylpiperazine and Ppreparation of Composite Nanofiltration Membrane

A new monomer,4-aminobenzoylpiperazine,was synthesized from 4-aminobenzoic acid and 1-formyl piperazine.The structure was identified by FT-IR and 1H NMR spectroscopy.The resulting 4-aminobenzoylpiperazine was used as an aqueous monomer to fabricate a thin film on porous polyethersulfone(PES)ultrafiltration membranes by interfacial polymerization with trimesoyl chloride(TMC)as organic monomer.The influence of monomer concentration on membrane performance was studied.The optimal concentrations of the monomers were 4-aminobenzoylpiperazine 1% and TMC 0.25%.The salt rejection of prepared composite nanofiltration membranes for Na2SO4 was 97.5%.