Corrosion resistant ZrO2/SiC ultrafiltration membranes for wastewater treatment and operation in harsh environments. Issue 15 (December 2021) - Bortot Coelho, Fabrício Eduardo
Graphical abstract: Highlights: Defect-free ZrO2 separation layer was obtained with pore size of 60 nm. The membrane presents a high permeability (360 Lm −2 h -1 bar -1 ) with low fouling. High retentions of humic acid, indigo dye, and hemoglobin were observed. In a pilot test, 99.91 % of oil was removed from an olive oil/water emulsion. No pore size change in long-term corrosion tests at basic and acid baths. Abstract: This work focused on the fabrication of a ZrO2 /SiC ultrafiltration membrane by dip coating a high porous SiC support with a ZrO2 slurry prepared by ceramic processing. The membranes were sintered in different temperatures (1000−1300 °C). With the optimal temperature, it was obtained a mechanically strong, homogenous, and defect free separation layer with 45 μm of thickness and average pore size of 60 nm. A pure water permeability of 360 L.m −2 h −1 bar -1 and high retentions of humic acid, indigo dye, and hemoglobin were observed. In a pilot test with an olive oil/water emulsion, 99.91 % of oil was removed without fouling. Long-term corrosion tests at basic and acid baths did not cause change in pore size and morphology. In conclusion, the ZrO2 /SiC membrane has potential to operate in harsh conditions ( e.g. heavily contaminated industrial effluents or urban wastewaters) and when severe membrane cleaning and disinfection are required, such as food and pharmaceutical industries.