Novel polyamide-hydrazide based reverse osmosis membrane with enhanced antifouling properties

The typical "ridge-valley" structure of traditional reverse osmosis (RO) membranes ensures good permeability with high risk of inducing membrane fouling. It is a challenge to develop a smooth RO membrane without loss of permeability. In this study, cyclobutane-1,2,3,4-tetracarbohydrazide (CBTH) was designed and synthesized, and a composite RO membrane based on CBTH and cyclobutane-1,2,3,4-tetracarboxylic acid chloride (BTC) was constructed. The CBTH-BTC membrane exhibits a smooth selective layer with thickness of 45 nm. The desalination performance test results show that the CBTH-BTC membrane has permeability and desalination performance comparable to the traditional RO membrane (the water permeability coefficient reaches 3.0 L·m−2·h−1·bar−1, and the rejection of NaCl reaches 99.2 %). Importantly, the hydrophilic and smooth surface imparts the membrane with good antifouling properties to hydrophilic, hydrophobic and surfactant pollutants. In this study, RO membranes with good permeability and excellent antifouling performance were successfully prepared from the perspective of reaction monomer design, which provides a new idea to regulate the morphology and antifouling properties of RO membranes.