Parametric optimization of alumina membrane fabricated via phase inversion for water treatment: Central Composite Design method

Abstract

Alumina membrane is widely used for microfiltration and ultrafiltration has been proven to be effective for water treatment. However, a certain thickness of the flat sheet configuration of alumina membrane limits the mechanical strength and water permeability. The present study applies central composite design (CCD) to optimize parametric study in fabrication of flat sheet alumina membrane. The obtained optimum condition at the blade gap of 1.0 mm and the sintering temperature of 1500 °C exhibits the highest mechanical strength of 697 MPa and pure water flux of 1716 L/m2.h as well as the desired shrinkage and porosity values of 13.86% and 45.18%, respectively. This optimization selection was validated against the ideal membrane morphology structure that has narrowest pore size distribution with peak diameter of 0.14 µm. Further with chemical stability using 1 M HNO3 and 1 M NaOH and results from FESEM-EDX found that there is no significant elemental weight loss. The selected membrane also had bovine serum albumin (BSA) recovery of 53.9 ± 2% at the flux recovery rate (FRR) value of 66.2 ± 2%.