Manipulating the organic-salt selectivity of N-2-hydroxyethylpiperazine based poly-ester-amide (PEA) membranes for antibiotic-NaCl separation

N-2-hydroxyethylpiperazine was used to prepare poly-ester-amide (PEA) nanofiltration membranes. • The organic-salt selectivity of the PEA membrane can be manipulated by adding NaOH as a catalyst of the IP reaction. • The N-2-hydroxyethylpiperazine based PEA membrane was used for incomycin hydrochloride desalination. • The N-2-hydroxyethylpiperazine based PEA-NF membrane show good antifouling performance. Precisely controlling nanofiltration (NF) membranes to achieve high-precision separation of organics and salts is a highly challenging topic. Interfacial polymerized (IP) poly-ester-amide (PEA) membranes offer more possibilities to tailor the pore and surface properties to achieve specific separation performance. This work introduces a type of N-2-hydroxyethylpiperazine (NAZ) based NF membranes, and the effects of monomer and NaOH concentrations on the membrane performance, especially for the selectivities, including organic salt selectivity and divalent salt-monovalent salt selectivity of the membranes, were investigated. It was found that the monomer ratio of TMC to NAZ and the concentration of NaOH in the NAZ solution are very sensitive to the selectivity of the resulting PEA membranes. The PEA-NF membrane prepared at an optimal condition exhibited a high organic-salt selectivity (78 for sucrose/NaCl), and maintained a good water permeance of 8.5 L·m −2 ·h −1 ·bar −1 . It fully rejected lincomycin hydrochloride (LH) and with >80% NaCl passage, showing good potential in antibiotic-salt separation. Meanwhile, the PEA membrane also presented good antifouling performance. This work highlights the advantage of PEA-NF membranes in organic salt separations and provides a reference for developing organic-selective nanofiltration membranes. Download: Download high-res image (69KB) Download: Download full-size image