Nanoscale phase transition seeds-assisted low temperature preparation of α-Al2O3 ultrafiltration membrane

α-Al 2 O 3 nanoparticles with a particle size of ~10 nm were synthesized from aluminum alkoxide precursor chelated by oxalic acid at 500 °C and added to boehmite sol as phase transition seeds (PTS) in low temperature preparation of α-Al 2 O 3 ultrafiltration (UF) membrane. With the PTS doping of 2.5 wt%, a single phase α-Al 2 O 3 membrane with small pore size of 7.2 nm was prepared at 950 °C. After long-term static and dynamic corrosion tests, the as-prepared α-Al 2 O 3 UF membrane was found to no significant degradation in performance, displaying a stable MWCO and water permeability of 15 kDa and 85 L/(m 2  h bar) respectively. In the decolorization of vinegar fermentation wastewater, the COD removal was 63% whereas the color removal could reach 98%. Furthermore, the contaminated membrane could be reused many times after cleaning, confirming the excellent durability and practicality of α-Al 2 O 3 UF membrane in wastewater treatment .