High temperature resistant polyamide thin film composite nanofiltration membrane based on polyethylene substrate

Abstract

High temperature wastewater is difficult and dangerous to treat, and it is necessary to take appropriate methods for treatment and recycling. Membrane separation technology is a novel approach for treating high-temperature wastewater with many benefits of enhanced efficiency, reduced energy consumption, and ecological preservation. However, most polymer composite membranes struggle with separation performance at high temperatures. Herein, we have successfully prepared a thin-film composite (TFC) nanofiltration (NF) membrane that is resistant to high temperatures, based on polyethylene (PE) substrate. The hydrophobic PE substrate was modified by tannic acid/diethylenetriamine (TA/DETA) coating, and then PA/PE TFC membrane was fabricated by interfacial polymerization (IP). The optimized PA/PE-60 membrane presented outstanding high-temperature resistance and stability. When the temperature rose to 90 °C, the permeance increased to 32.9 L m⁻² h⁻¹ bar ⁻¹, and the Na₂SO₄ rejection remained at 98.1 %. Overall, our work provides a method to prepare high temperature resistant NF membranes.