What is a Cermic Membrane made of?

Silicon carbide is a synthetically produced crystalline compound containing pure silicon and pure carbon. Silicon carbide is the second hardest material in the world, only exceeded by diamonds, and the hardest man-made material ever made. On Mohs Scale, which measures mineral hardness based on an ordinal scale ranging from 1-10, SiC scores 9.5, while diamonds score 10. Due to its strength and durability, silicon carbide has been employed for various industrial applications since the late 19^th century, when the material was first produced. Silicon carbide was made in an attempt to create artificial diamonds. Now, this element has found its way to ceramic membranes for liquid filtration, providing a porous support structure, which filtered water can permeate. Due to its hardness, SiC ensures thermal and mechanical stability, which is vital for many industrial applications, especially if frequent cleaning or sterilization processes are required. Using solid and long-lasting material secures a high-quality product with long service life and unique advantages.

Coating and sintering ensure high performance and endurance. The silicon carbide grains are sintered together into a membrane with one or several parallel flow channels for the water to flow and retain the unwanted particles.

The sintering of silicon carbide involves a temperature of approximately 2100°C, whereas oxide-based membranes are sintered at merely 1200-1600 °C. Producing silicon carbide ceramic membranes demand correct manufacturing equipment, experience, caution, and clearly defined preventative measures.

A special coating is placed in the ceramic membrane’s flow channels to achieve the desired effects. This unique coating material containing silicon carbide is dried and sintered at a high temperature in an inert atmosphere. The exclusive coating layer equips the membranes with their ruggedness and durability, but it also determines the membranes’ flow channel pore size and water flux. Dive into how a ceramic membrane is manufactured and the unique ceramic membrane coating. 

Silicon carbide provides a porous support structure, which filtered liquid can permeate while impurities are rejected. Moreover, SiC delivers the highest water flux for any membrane material, making silicon carbide ceramic membranes capable of handling even the most complex and strenuous liquid filtration tasks. Add to this, silicon carbide enables reduced fouling, which reduces downtime caused by backwash and chemical cleaning-in-place (CIP). This is supported by the material’s hydrophilic attributes, meaning that silicon carbide is water-loving as the material’s surface absorbs liquids and repels oils. Furthermore, silicon carbide is inert in all pH values from 0-14 and thermally resistant up to 800°C. Lastly, SiC contributes to low power usage and low pressure. All these advantages and features ensure that silicon carbide ceramic membranes can operate effectively with long service life. This has made SiC a key player in manufacturing ceramic membranes for water filtration systems.

• Hydrophilic material
• Chemically inert pH 0-14
• Thermally resistant up to 800°C
• Low power usage and low pressure
• Long service lifetime