Enhanced performance arising from low-temperature preparation of Α-alumina membranes via titania doping assisted sol-gel method

A high-efficiency alumina-titania membrane was proposed and fabricated, by using a titania-doping assisted sol-gel method. Two kinds of aqueous titania sols with different particle size distributions were introduced into boehmite sol. The phase transition temperature of alumina from γ to α phase is prone to reducing with the aid of titania doping of 10 dwb%, thus a good α phase membrane was obtained under a relatively lower thermal treatment of 1050 °C. Compared to the α-alumina membrane without the titania addition, the resultant Al₂O₃-TiO₂ membrane presented a better separation precision and higher water permeability. The average pore size was decreased from 16.0 to 9.8 nm, while the pure water permeability was improved from 200 to 233 L m⁻² h⁻¹ bar⁻¹.