NUS Enterprise

Cost Effective Kaolinite-Based Porous Ceramic Supports with High Permeability and Mechanical Strength

Technology #13322n

Cost Effective Kaolinite-Based Porous Ceramic Supports with High Permeability and Mechanical Strength

HONG Liang; CHEN Xinwei; ZHOU Yi’en

Department of Chemical & Biomolecular Engineering

Industry Problem

Ceramic membranes are made of inorganic materials such as alumina, titania, zirconia oxides, silicon carbide. Advantages of ceramic membranes are (1) high chemical, mechanical and thermal stability; (2) high abrasion resistance; (3) high durability. Disadvantages are high weight and considerable production costs of ceramic components.

To lower costs, it is preferred to use low cost inorganic materials e.g. kaolinite (clay). However, kaolinite is deemed to be unsuitable as a material for inorganic membranes due to its poor sinterability and consequently, a matrix with poor mechanical strength due to weakly jointed particles.  This  is  due  to  the  structure  of  kaolinite,  which  comprises  of  randomly  oriented individual stack of flakes and thus, difficult to achieve good contact between the particles for the onset of necking during sintering. Furthermore, kaolinite’s sintering temperature is less than

1200 °C to prevent phase separation to mullite and highly crystalline cristobalite, SiO2. 


This technology relates to a mechanically stable (4 ‐ 32 MPa) and highly permeable (Darcy's permeability of ~1.4 x 10‐15  to

1.5 x 10‐13  m2) porous ceramic which is made from doped kaolinite, depending on how the dopant is varied. The dopant is

used in a small percentage. The pore size of the structure can be tailored according to the needs of the end user. The technique of fabricating the porous structure is also applicable to the fabrication of planar porous ceramic membrane or panels.


Figure 1:   Micrographs   of   sintered   doped‐kaolinite matrix at 5% dopant level

Figure 2: Pore size distribution of the sintered kaolinite matrix (1150°C for 6 h) with varying degree of doping (0% to 20%)

Figure 3: An example of mechanical strength and Darcy’s permeability of a doped sintered kaolinite matrix with varying degree of doping (0% to 20%)

Value Proposition

·  Cost effective

·  Low sintering temperature (<1200 deg C) compared to other ceramic materials.

·  Tunable pore size from 1 – 10 μm with varying mechanical stability and permeability.

·  High mechanical strength (up to 32 MPa).

·  High permeability (up to 1.5 x 10‐13 m2) due to interconnected pore channels with the structure.

Other Potential Application

·  Catalyst support

·  Energy storage and accumulation

·  Thermal and acoustic insulation

·  Impact absorption

·  Lightweight structures

For more information, contact:

NUS Industry Liaison Office

  :+65 6516 7175



Ref : 13322N

Principal Investigator: Assoc. Prof. Hong Liang


This research is supported by the Singapore National Research Foundation under its Environment & Water Research Programme and administered by PUB, Singapore’s national water agency.