Overcoming the Trade-off between Water Permeation and Mechanical Strength of Ceramic Membrane Supports by Interfacial Engineering

Abstract

Porous ceramic membrane supports with high mechanical strength and permeation are required for highly permeable ceramic membranes. The water permeation of a ceramic membrane support is largely dependent on its level of open porosity, which can be however generally detrimental to the mechanical strength. In this work, low-cost kaolin nanoflakes were rationally composited with coarse alumina particles, and multichannel flat-sheet ceramic supports were successfully fabricated by extrusion and subsequent partial sintering. The macroscopic properties, microstructure characteristics, permeability, and mechanical strength of the ceramic membrane supports were systematically established and comprehensively studied. The incorporation of kaolin nanoflakes effectively reduced the sintering temperature to about 1200 °C. An interesting evolution of the pore structure was evidenced with the increase in sintering temperature. Interestingly, the porous ceramic supports prepared at 1400 °C with a nominal pore size of 1.47 μm showed the highest water permeability of 9911.9 ± 357.5 LMHB, and at the same time the flexural strength reached 109.6 ± 4.6 MPa. The much improved permeability was attributed to the unique multilevel pore structures, and the enhanced flexural strength mainly originated from the strongly interfacial bonding, as evidenced by the trans-granular fracture behavior. Also, the ceramic membrane supports exhibited excellent chemical resistance and good removal efficiency for oily wastewater. This work highlights the significant role of interfacial engineering in simultaneously improving the water permeation and mechanical strength, thereby overcoming their trade-off in porous ceramic membrane supports.

Preparation and application of microfiltration porous coal gangue–loess‐based ceramic membrane

“…The reason is that there is a large amount of SiO 2 in the raw material, and when it reacts with H 2 SO 4 and NaOH, the Gibbs free energy is small, which is prone to reverse reaction. However, H + is more prone to react than OH − , so the acid corrosion rate is higher than the alkali corrosion rate 21,23 …”

“…However, H + is more prone to react than OH − , so the acid corrosion rate is higher than the alkali corrosion rate. 21,23…”

Spatially confined growth of carbon nanotubes in the pore channels of microporous ceramic supports with improved filtration efficiency

“…It can be attributed to that CNTs spatially confined in SiC-100 formed a stable membrane structure, which can effectively retain oil droplets, thereby causing the gradual accumulation of oil droplets on the membrane surface. 50 The stable permeation flux of CNTs-300-SiC and CNTs-900-SiC reached 782 L m −2 h −1 and 282 L m −2 h −1 after 40 min, respectively. This was related to the dynamic saturation of membrane fouling caused by oil droplets, resulting in the stable permeate flux.…”

Effects of Pore Arrangement of TiO2-Coated Porous Alumina Membranes on Photocatalytic Properties

“…Porous membranes with photocatalytic properties are expected to be applied in environmental purification as membrane filters to separate and remove harmful organic substances. − Decomposition of pollutants using porous membranes with photocatalytic properties is an environmentally friendly, sustainable, and energy-saving technology. To use membranes to separate and decompose pollutants, it is important to control the pore size to match substances and provide high photocatalytic properties.…”