Preparation of ZrO2/TiO2/Al2O3 Nanofiltration Lab-Scale Membrane for Filtering Heavy Metal Ions

Abstract

ZrO2 is an excellent ceramic preparation material that can maintain chemical stability in medium–strong acid and alkali environments. The sintering impregnation method was used to prepare the ZrO2/TiO2/Al2O3 composite nanofiltration membrane (ZTA membrane). Nano-ZrO2, submicron TiO2, and microporous Al2O3 were used as the surface layer, the transition layer, and the support layer, respectively. The structure and phase of the membrane were measured by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The composite membrane’s retention, hydrophilic and hydrophobic properties were characterized and evaluated using a UV–Vis spectrophotometer, a water contact angle tester (WCA), and a dead-end filtration device. With the increase in separation layer deposition time, the retention rate of methyl blue increased, and the water flux decreased. At a deposition time of 75 min, the retention rate of methyl blue was more than 80%, and the water flux reached 337.5 L·m−2 h−1 bar−1 at −1 bar transmembrane pressure. The membranes are hydrophilic and have different interception abilities for metal ions, and the order of retention effect is Ag+ > Cu2+ > Mg2+ > Na+, and Ag+ and Cu2+ reached 65.3% and 50.5%, respectively. The prepared ZTA composite nanofiltration membrane has potential application value in heavy metal ion filtration.