Development Of Ceramic Membranes Research Articles

Construction of anti-fouling ceramic tubular membranes with corrugated inner surfaces using DLP 3D printing

The challenge of membrane fouling persistently hinders the advancement of membrane technology. The construction of patterned membrane surfaces is anticipated to mitigate the effects of membrane fouling significantly. In this study, ceramic microfiltration membranes with corrugated patterns were fabricated by 3D printing combined with the dip-coating process. To assess the impact of surface patterning on ceramic membrane performance, we initially compared the pore size and pure water flux between straight and corrugated membrane tubes. Both configurations exhibited similar parameters: a support pore size of approximately 1 μm, a membrane layer pore size of about 110 nm, and a pure water permeance of around 950 L m−2 h−1·bar−1. The corrugated ceramic membranes demonstrated superior anti-fouling properties compared to their straight counterparts during the filtration of nanoparticle suspensions, oil-in-water emulsions, and bacterial suspensions. Specifically, under a nanoparticle suspension concentration of 2000 ppm, a transmembrane pressure of 0.2 MPa, and a flow rate of 1.0 m s−1, the corrugated membrane achieved a stable flux of approximately 1.7 times greater than that of the straight membrane. Furthermore, we explored the effects of surface patterning on fluid dynamics through numerical simulations. The enhanced turbulence dissipation rate in the patterned membrane tubes suggests increased surface turbulence and an improved capacity to remove contaminants. This research offers novel insights into the development of ceramic membranes with enhanced anti-fouling capabilities for water treatment.

A comprehensive study on the development of ceramic membranes from natural Kashmir clay and its application in pH-mediated removal of Indigo carmine dye

A comprehensive study on the development of ceramic membranes from natural Kashmir clay and its application in pH-mediated removal of Indigo carmine dye

Tuning Nanopores in Tubular Ceramic Nanofiltration Membranes with Atmospheric-Pressure Atomic Layer Deposition: Prospects for Pressure-Based In-Line Monitoring of Pore Narrowing

Atomic layer deposition (ALD) is known for its unparalleled control over layer thickness and 3D conformality and could be the future technique of choice to tailor the pore size of ceramic nanofiltration membranes. However, a major challenge in tuning and functionalizing a multichannel ceramic membrane is posed by its large internal pore volume, which needs to be evacuated during ALD cycling. This may require significant energy and processing time. This study presents a new reactor design, operating at atmospheric pressure, that is able to deposit thin layers in the pores of ceramic membranes. In this design, the reactor wall is formed by the industrial tubular ceramic membrane itself, and carrier gas flows are employed to transport the precursor and co-reactant vapors to the reactive surface groups present on the membrane surface. The layer growth for atmospheric-pressure ALD in this case proceeds similarly to that for state-of-the-art vacuum-based ALD. Moreover, for membrane preparation, this new reactor design has three advantages: (i) monolayers are deposited only at the outer pore mouths rather than in the entire bulk of the porous membrane substrate, resulting in reduced flow resistances for liquid permeation; (ii) an in-line gas permeation method was developed to follow the layer growth in the pores during the deposition process, allowing more precise control over the finished membrane; and (iii) expensive vacuum components and cleanroom environment are eliminated. This opens up a new avenue for ceramic membrane development with nano-scale precision using ALD at atmospheric pressure.

High efficiency manganese cobalt spinel structure catalytic ozonation ceramic membrane for in situ BPA degradation and membrane fouling elimination

In recent years, micropollutants contamination in aquatic environments has received increasing attention. Bisphenol A (BPA), an endocrine-disrupting compound, has emerged as a substantial threat to water safety owing to its widespread presence in various aquatic environments. To address this issue, this study focused on the development of ceramic membranes incorporating manganese-cobalt oxides (MCOs) to catalyze the ozone-based degradation of BPA. The catalytic layer was prepared by hydrothermal in-situ growth method, which enhanced BPA degradation during water treatment and improved the ceramic membrane’s resistance to contamination. Moreover this study investigated the synergistic effect of catalytic ozone oxidation in mitigating ceramic membrane pollution and degrading micropollutants. The catalytic mechanism and the contamination modeling were examined systematically to determine the mechanism of micropollutant contamination on ceramic membranes. The experimental results showed that the modified ceramic membrane exhibited a higher BPA removal efficiency (90.6%) and flux recovery (99.5%) than the unmodified membrane (64.2% and 79%, respectively). Furthermore, the MCOs-modified ceramic membrane (CCM) effectively enhanced the generation of hydroxyl radicals during ozonolysis. This enhancement resulted in better degradation of organic pollutants in water, thus improving the quality of the treated water. The combination of ceramic membrane catalytic separation with ozone oxidation technology offers a potential solution for the degradation of emerging pollutants and the mitigation of ceramic membrane pollution.

Development of ceramic membranes with controllable PFAS mass transfer for passive sampling applications

Polar organic chemical integrative sampler (POCIS) represents a promising passive sampling approach for the monitoring of per- and polyfluoroalkyl substances (PFAS) in water. However, the use of polymer membranes has limited the long-term application of conventional POCIS in the field. This work aimed to develop ceramic membranes with controllable PFAS diffusion and mass transfer suitable for PFAS passive sampling applications. Our results showed that PFAS diffusion through ceramic membranes was strongly dependent on membrane structures and properties, particularly membrane porosity. Through controlling membrane fabrication conditions, including particle size and morphology of the membrane material and sintering temperature, ceramic membranes with a range of PFAS diffusivities and mass transfer rates were obtained that varied by over two orders of magnitude, which substantially expanded the limits of polyethersulfone (PES) membranes. Further, modification of ceramic membranes with a thin TiO2 layer did not influence the PFAS mass transfer. Integrative passive samplers consisting of ceramic membranes and a sorbent receiving phase were then developed and assessed through calibration studies. The passive samplers showed linear uptake of PFAS over an extended period of time up to 25 days, and the PFAS sampling rates were affected by both the type of ceramic membranes and the PFAS structures. Results of this study demonstrated the proof-of-concept of the use of ceramic membranes in PFAS passive sampling applications.

Characterization and application of novel fly ash blended ceramic membrane in MFC for low-cost and sustainable wastewater treatment and power generation.

Field-scale application of the microbial fuel cell (MFC) technology faces a major constraint due to the widely used high-cost proton exchange membrane Nafion, prompting lately, the development of ceramic membranes using different clay minerals. In the present study, the characteristics and applicability of a novel ceramic membrane fabricated using potter's clay (C) blended with varying proportions (0, 5, 10, and 20wt%) of fly ash (FA), designated as CFA0, CFA5, CFA10, and CFA20, were assessed for cost-effective and sustainable use in MFC. On assessing the properties of the membrane, CFA10 was found to exhibit superior quality with fine pore size distribution (average 0.49μm) favoring higher water uptake and less oxygen diffusion. The CFA10 membrane showed a maximum proton mass transfer coefficient (4.32 ± 0.04 × 10-5cm/s) that was about three times that of the control CFA0. The oxygen mass transfer coefficient of CFA10 was 5.13 ± 0.12 × 10-5cm/s, which was about 40% less than in the control. X-ray diffraction (XRD) analysis of CFAmembrane revealed the richness of quartz, which facilitates proton conductance and water retention. The CFA10 membrane fitted MFC demonstrated a peak power output of 4.57W/m3 (twice that in CFA0) with an average of 80.02 ± 0.86% COD removal and 68.03 ± 0.13% coulombic efficiency in a long-term study indicating its improved applicability and durability. Electrochemical kinetics involving cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) also affirmed the efficacy of CFA10 membrane in MFC showing peak current output of 13.95mA and low ohmic resistance (74.2 Ω). The novel (CFA10) ceramic membrane amalgamated with the coal fly ash, a waste of concern, shows promise for high MFC performance at a much reduced (98% less) cost that can be used for sustainable scale-up of the technology.

Development of ceramic membranes for resource recovery from brine through percrystallization

Availability of efficient methods to fractionate a solution into its solid and liquid components is the key to recycling and reuse of industrial effluents. Percrystallization is a novel membrane process where a thin film of warm permeate present at the membrane surface is evaporated through vacuum to crystalize the soluble compounds. Thus, the process separates a solution into crystalline solute and solvent in a single-step and can partly be operated with sustainable sources of energy such as solar and geothermal heat. Since the process is at early stage of exploration, there is no sufficient knowledge about the suitable membrane features for the percrystallization which hampers its further development and potential progress towards commercialization. This work performs a systematic and groundbreaking investigation to identify and develop suitable membranes for percrystallization applications. The study has been carried out by using silicon carbide (Si-C) and polymeric membranes with different porosities and thicknesses. The effect of pore size and surface hydrophobicity on the process operation was investigated by coating the surface of Si-C membranes with methylated silica particles of different sizes. Inherent hydrophobicity of the polymeric membranes was also modified to test their suitability for the percrystallization applications. All the membranes were tested for separation of NaCl crystals from solution by using different concentrations (3.5, 10 and 17.5 wt%) of NaCl at operating temperatures of 50 °C, 55 °C and 60 °C. It was observed that the membranes with the rate of permeation comparable with the rate of evaporation under the applied vacuum are crucial to operate the process. Thus, only less porous and thick Si-C membranes with liquid entry pressure approaching to 1 bar were suitable for percrystallization. The developed membranes yielded water and NaCl flux in the range of 9.43±2 and 1.2 kg/m2.h, respectively. The process outperformed state-of-the-art membrane processes in terms of productivity and simplicity.

Development of a ceramic membrane for emulsion water-diesel treatment

The purpose of this study was the development of a low-cost ceramic tubular membrane, using inexpensive materials, namely natural clay, and graphite as a porogenic agent. Such a low-cost membrane can be used as filters or porous supports for the preparation of multilayer ceramic membranes. Extrusion was used as a shape-forming method for this purpose. Graphite was selected as a porogenic additive. Raw materials were physicochemically and morphologically characterized. A comparative study of the influence of porogen content on membrane characteristics was carried out. Finally a graphite addition of 15 wt% and 850 °C as the sintering temperature were chosen. The obtained membrane had 41 vol% of porosity, diametral compression strength of 4 MPa, and relatively good corrosion resistance in basic and acid conditions. The performance of the membrane support was evaluated for diesel-in-water emulsion depuration as a function of pressure. Filtration test using 15% of porogen sample led to turbidity rejection factor of 95%. Therefore, it was considered that this membrane can be suitable for diesel/water emulsion treatment.

Fabrication and characterisation of hollow fibre ceramic membranes from fly ash

The development of ceramic membrane to treat wastewater is generally limited due to the fact that materials commonly used for fabrication of these membranes such as high purity alumina (e.g. Al 2 O 3 ) are expensive. Thus, the aim and purpose of this present work is to fabricate and characterize low-cost ceramic membranes using abundant and low-cost fly ash as the raw material. However, the presence of unburnt carbon in fly ash would significantly increase membrane porosity which would affect the mechanical strength and removal efficiency. Thus, it is of paramount importance to determine the optimum loading of fly ash during preparation of precursor solution. In the present work, the membrane precursors were prepared using three different fly ash loadings, i.e. 40wt%, 45wt%, and 50wt%. The membranes were fabricated via phase inversion technique and sintered at 1250°C. The membranes were then characterised in terms of its density, shrinkage, volumetric porosity, mechanical strength, and equilibrium water content. The results obtained show that at 45wt % loading, the membrane produced exhibited optimum properties with percent shrinkage, density, and bending strength of 52%, 1.28g/cm 3 , 37MPa, respectively. The higher shrinkage of 45wt% loading membrane as compared to other loadings also affects the cross-sectional morphology of membrane, exhibiting a spongy structure with smaller macrovoids at an average pore size of 7.8µm. In addition, the 45wt% loading membrane was also less porous as compared to other membranes, with 26% porosity and 39% to achieve equilibrium water content.

Analysis of ceramic membrane fouling behavior and cleaning technology

In this paper, while ceramic membrane fouling and its causes were introduced, the calculation of ceramic membrane fouling resistance, membrane fouling analysis methods and several common ceramic membrane cleaning techniques were summarized. In this process, some factors affecting the cleaning effect were also analyzed by enumerating cases, and the future development of ceramic membrane was prospected.

Effect of gradient profile in ceramic membranes on filtration characteristics: Implications for membrane development

A proper gradient structure in ceramic membranes can reduce the thickness of the top active layer and therefore enhance the filtration performance and enable a good mechanical stability simultaneously. We designed and fabricated different gradient ceramic membranes including 1-, 2-, and 3-layer ceramic membranes using a simplified single sintering process. To the best of our knowledge, the preparation of the ceramic membrane with gradient porous structure within the top layer and the effect of gradient profile on filtration performance have not been investigated to date. The gradient profile in the top layers can be easily controlled by choosing the slurries with different alumina grain sizes. The 3-layer membrane exhibited the highest water flux and the lowest membrane resistance due to the advantages of gradient porous structure. It retarded internal fouling because foulants smaller than the surface pore size in the gradient porous structure could be easily swept through the membrane by permeate flow as demonstrated by particle size retention tests. Fouling mechanisms were largely size dependent and were similar between different membranes. Transitionary stage between pore blocking and cake filtration was observed from bovine serum albumin (BSA) and sodium alginate foulants but not from activated sludge. Rate and severity of membrane fouling decreased with increasing gradient profile in ceramic membranes. The gradient membrane has the lowest total resistance. This study demonstrated a breakthrough in ceramic membrane development, i.e., developing the gradient porous membrane to enhance the filtration performance.

Development of hollow fiber membranes with alumina and waste of quartzite

The development of ceramic membranes with different geometries and compositions extends the possibilities of industrial applications, inducing advantages in terms of increased permeability, membrane area by volume module and chemical, thermal and mechanical resistance. The use of low-cost raw materials is a trend that has grown in scientific research. The aim of this work is to prepare membranes with hollow fiber geometry from alumina and residue of quartzite, by the technique of immersion precipitation in distilled water from a mixture of ceramic mass with a solution of polyethersulfone and, synthesized in temperatures of 1100 oC to 1500 °C. The hollow fiber membranes were characterized by chemical analysis, X-ray diffraction, particle size distribution, scanning electron microscopy, apparent porosity, flexural strength and permeated water flow by the membranes. The results indicated that the sintering temperature has direct influence on the formation of the mullite phase, and the properties of apparent porosity and permeate flow. The higher the sintering temperature (1400-1500 ° C) increase the formation of the mullite phase, the lower the porosity, as well as the lower the permeate water flow in the membranes. However, there was increase in flexural strength in the hollow fiber membranes with high temperature.

Influence of sintering temperature on the development of alumina membrane shaped by centrifugal casting for gas separation

Abstract The development of ceramic membranes for the most diverse separation processes has gained high visibility, mainly due to their better performance in harsh environments in comparison to polymeric materials. Among the different techniques used to prepare tubular ceramic membranes, the centrifugal casting (CC) is interesting for obtaining highly homogeneous structures, essential for gas separations. This study assessed the influence of two sintering temperatures (1450 and 1500 °C) of alumina membranes prepared by CC on the membrane morphology and on the permeation of helium, nitrogen and oxygen gases. The membranes were characterized by their morphology, apparent porosity, and gas permeation. The results indicated that the sintering temperature is a fundamental parameter for controlling membrane properties, an increase of only 50 °C led to a tenfold decrease in the gas permeate flux, indicating densification of membrane porous structure. This was in accordance with the results observed in the membrane micrographs and the apparent porosity.

Development of porous ceramic membrane from natural zeolite – clay for microfiltration

Indonesia has a large amount of natural zeolite and clay. These materials are potential for ceramic membrane production. The aims of this study were to describe the characteristic of ceramic membrane development from natural zeolite and clay. With an addition of TiO2, ceramic membrane was produced by dry process by pressing at 5 tons for 30 minutes. From the results of the investigation, it can be concluded that the natural zeolite and clay from Banyumas may be utilized for obtaining ceramic membranes for microfiltration at low sintering temperature of 900°C. Optimum addition of TiO2 was 5%wt. At this condition, the densities of ceramic membranes were 1.44 gr/cm3, 1.8 gr/cm3, and 1.5 gr/cm3. The porosities of ceramic membranes were 53.29%, 31.099%, and 35.42%. The water absorption values of ceramic membranes were 36.83%, 17.06%, and 23.61% for natural zeolite, clay, and natural zeolite – clay respectively.

Evaluating the feasibility of pyrophyllite-based ceramic membranes for treating domestic wastewater in anaerobic ceramic membrane bioreactors

This study laid great emphasis on anaerobic ceramic membrane bioreactor (AnCMBR) treatment of domestic wastewater for facile and enhanced energy recovery. To this end, the performance of the natural-based ceramic (i.e., pyrophyllite-based) membranes was mainly explored in this study by evaluating filtration and treatment performances. 92.9±5.5% chemical oxygen demand (COD) removal and stable methane production were successfully achieved in a bench-scale AnCMBR while maintaining a slightly long hydraulic retention time (HRT). Comparative filtration experiments with commercialized ceramic membranes suggested that the pyrophyllite-based membrane separation in AnCMBR treatment of wastewater at long HRT is feasible. However, short HRT operations resulted in substantial levels of sludge washout. Future improvements of AnCMBR technology in cost-effective ceramic membrane development, increased flux, and harsh environmental conditions would make AnCMBR competitive with anaerobic membrane bioreactor (AnMBR) technology.

Synthesis of zeolite and γ-alumina nanoparticles as ceramic membranes for desalination applications

Development of ceramic membrane for desalination is gaining interest in order to provide fresh water for human’s life. In this work, a ceramic membrane was developed by coating of porous geopolymer with nanoparticles of gamma alumina (γ-Al2O3) (Al membrane), zeolite (Z membrane), and its combination (Al-Z membrane) which were synthesized through a sol-gel method. Nanoparticles of γ-Al2O3 exhibit rod structures with 10–20 nm in diameter and 40–70 nm in length, a surface area of 326.26 m2/g, total pore volume of 0.10 cm3/g, and an average pore diameter of 2.10 nm. Zeolite nanoparticles were obtained from a composition of 6Na2O: 0.55Al2O3: SiO2: 150H2O having particle sizes in the range from 100 to 400 nm, a surface area of 97.32 m2/g, total pore volume of 0.80 cm3/g, and an average pore diameter of 11.19 nm. The performance of membranes was evaluated by measuring the salt rejection and the flux of NaCl 1% (w/v) solution that was passed through the membrane. The Z membrane demonstrated the highest salt rejection, up to 87.88%, whereas the Al-Z membrane reached 68%. The Al membrane exhibited the lowest salt rejection rate, amounted to 57.14%. The highest flux was obtained using Al membrane, which was to 3.43 × 103 L/m2h on the 54.29% rejection value; whereas the Z membrane reached 3.28 × 103 L/m2h on the 87.88% salt rejection value, and the lowest flux of 2.91 × 103 L/m2h showed by the Al-Z membrane at the 62% salt rejection value. It is promising to use the synthesized γ-Al2O3 and zeolite nanoparticles as alternative ceramic membrane materials to be applied in the desalination.

Development of Ceramic Membrane for Metal Ion Separation of Lignin Extract from Pulp Process

Development of Ceramic Membrane for Metal Ion Separation of Lignin Extract from Pulp Process

Nanoporous ceramic membranes modified by carbon nanotubes used to separate gaseous mixtures

Studies devoted to the development of ceramic membranes, which are capable of separating gaseous mixtures, first and foremost of H2–CH4, are presented in this paper. The membranes from alumina prepared on the basis of thermochemical activation (TCA) products of gibbsite contain a considerable amount of macropores and possess low selectivity in gas separation. In order to reduce the contribution of macropores to the porous structure of membranes, we have introduced glass additives, which sinter more easily than alumina. Tests of the samples, in which a part of TCA product is replaced by glass, have shown that the factor of separation for gaseous mixtures of H2–CH4 increases to 2.2. In the next part of this work, we synthesize the ceramic membranes, which were modified by carbon nanotubes (CNTs) with an external diameter of 3–5 nm. It is shown that when CNTs are introduced into the composition of a ceramic membrane, the selectivity in the separation of gaseous mixtures of H2–CH4 increases to 2.4.

Development of ceramic membranes from low-cost clays for the separation of oil–water emulsion

This work addresses the fabrication of ceramic microfiltration membranes by uniaxial dry compaction method. Four membranes, namely SP1, SP2, SP3, and SP4 were prepared with various compositions of fly ash and titanium dioxide (TiO2) followed by sintering at 1,100°C. The raw materials and the prepared membranes were characterized by particle size distribution, X-ray diffraction and field emission scanning electron microscope, porosity, pore size, and chemical and mechanical stabilities. As the TiO2 content increases in the precursor formulations, the porosity and mechanical stability of the membranes also increase while the average pore size reduces from 2.97 to 1.32 μm. The chemical stability of all the membranes demonstrates to be better in both acidic and basic medium. The performance of the membrane (SP4) is examined for the separation of oil–water emulsion and the membrane exhibits a maximum oil rejection of 99.2%.

Facile fabrication and improved carbon dioxide tolerance of a novel bilayer-structured ceramic oxygen permeating membrane

An asymmetrical Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF)|Pr0.5Ce0.5O2−δ (PrCe) bilayer-structured ceramic membrane is fabricated by a facile technique involving dry pressing of BSCF substrate, wet spraying of PrCe thin film layer (~10μm) and co-sintering of the bilayer structures. The phase reaction, sintering behavior and oxygen permeability of the membrane are systematically investigated using XRD, ESEM, EDX and oxygen permeation studies. The CO2 poisoning resistance of the layer materials is characterized by FTIR and CO2-TPD experiments. The large shrinkage of BSCF substrate and the diffusion of compositional elements from BSCF substrate into the PrCe layer promote the densification of PrCe layer at a temperature as low as 1100°C. The as-fabricated bilayer membrane exhibits not only high oxygen permeation flux, reaching 1.6mLcm−2min−1 at 850°C, but also favorable permeation stability even after the introduction of 10% CO2 into helium sweep gas. After the continuous operation at 850°C under the CO2-containing atmosphere for 800min, the permeation flux remains stable at around 1.35mLcm−2min−1. The facile fabrication and superiority of the bilayer-structured membrane in resistance towards CO2 poisoning thus provides a new way for the development of ceramic membranes for oxygen separation.