Ceramic Membranes

Ceramic membrane is one of the inorganic membranes. It is a solid membrane material in membrane separation technology. It mainly uses different specifications of inorganic ceramic materials such as alumina, zirconia, titania and silica as the support. Ceramic membrane has high separation efficiency, stable effect, good chemical stability, acid and alkali resistance, organic solvent resistance, bacteria resistance, high temperature resistance, pollution resistance, high mechanical strength, good regeneration performance, simple separation process, low energy consumption, operation and maintenance. It has many advantages such as simplicity and long service life. It has been successfully used in many fields such as food, beverage, plant (medicine) deep processing, biomedicine, fermentation, fine chemical industry, etc. It can be used in the separation, clarification, purification, concentration, and removal of the process Bacteria, desalination, etc.

Applications:

Figure 1. Ceramic membrane are used in oil - water separation.

• Wastewater treatment: Membrane bioreactor is a new type of water treatment technology combining ceramic membrane separation unit and biological treatment unit. It has the advantages of high treatment efficiency, good effluent quality and simple operation. At present, ceramic membranes are mainly used for the treatment of oily wastewater, chemical and petrochemical wastewater, papermaking and textile wastewater, domestic wastewater and launching wastewater.
• Catalytic reaction: Combining ceramic membrane with catalytic reaction constitutes the catalytic reaction of ceramic membrane. Membrane catalysis is mainly because the membrane itself is a catalyst and has catalytic activity, or the membrane is treated with a catalytically active substance and has a catalytic function. The initial successful application of membrane catalysis is the use of thin-walled palladium membranes in the hydrorefining of ethylene and in the perfume and pharmaceutical industries with particularly high hydrogenation selectivity requirements.
• Sterilization and filtration: The application of ceramic membrane in the food industry is mainly to solve food quality problems. It can be used to sterilize and filter milk, fruit wine, beverages, liquor, etc., and the effect is very significant. The special feature is that steam can be used to sterilize the entire equipment, which guarantees the product quality.

Classification:

• Tubular ceramic membranes: The wall of the tubular ceramic membrane tube is densely covered with micropores. Under the action of pressure, the raw material liquid flows inside or outside the membrane tube. Small molecular substances (or liquids) penetrate the membrane, and large molecular substances (or solids) are trapped by the membrane to achieve separation, concentration, purification and environmental protection purposes.
• Flat ceramic membranes: The surface of the flat ceramic membrane is densely covered with micropores. According to the range of the membrane pore size, the permeability of the molecular diameter of the substance is different. The pressure difference between the two sides of the membrane is the driving force, and the membrane is the filter medium. Under a certain pressure when the feed liquid flows through the surface of the membrane, only water, inorganic salts, and small molecular substances are allowed to pass through the membrane, and macromolecular substances such as suspended solids, glues and suspensions of microorganisms are prevented in the water.

References:

1. S. Smart, C. X. C. Lin, L. Ding, K. Thambimuthu and J. C. Diniz da Costa. Environmental applications of graphene-based nanomaterials [J]. Energy Environ. Sci., 2010, 3, 268–278.
2. Chi Zhang, Jaka Sunarso and Shaomin Liu. Designing CO₂-resistant oxygen-selective mixed ionic–electronic conducting membranes: guidelines, recent advances, and forward directions [J]. Chem. Soc. Rev., 2017, 46, 2941-3005.
3. Gilvan Barroso, Quan Li, Rajendra K. Bordia and Gunter Motz. Polymeric and ceramic silicon-based coatings – a review [J]. J. Mater. Chem. A, 2019, 7, 1936–1963.