Inorganic Membranes Research Articles

A low-cost photo-evaporation inorganic membrane preparation and treatment of the simulated high salinity radioactive waste water

Solar-driven desalination is an energy-saving and environmentally benign wastewater treatment technology. A method of in situ self-reduction of graphene oxide (rGO) by cheap geopolymer was introduced, and a photo evaporation membrane device (rGOPGC) for treatment of the simulated high salt liquid radioactive waste (HSLRW) was prepared in the present study. Compared with other rGO based photo evaporation membrane materials, geopolymer matrix has the advantages of low cost, reductant free, simple preparation process and mild conditions. After desalination of simulated seawater, the concentrations of Na+, K+, Ca2+ and Mg2+ ions reached the WHO standard, and the removal rates of radioactive I-, Cs+ and Sr2+ in the simulated high salinity wastewater reached 99.62%, 99.71% and 99.99% respectively; The evaporation rate of rGOPGC remained stable at 1.5 kg/m2/h after 16 cycles in high salinity environment. There was no obvious salt accumulation on the upper surface of the device, indicating its high stability. Furthermore, the evaporation performance at high temperature near the nuclear power plant (NPP) waste water was simulated and tested. Under one solar intensity and 35 °C ambient temperature, the evaporation rate of 1.75 kg/m2/h and the evaporation efficiency of 98.51% were achieved. The results indicated that the rGOPGC device is potential in the concentration evaluation of HSLRW.

Incorporating silica-magnetite synthesized from natural resources into the cation exchange membranes

Inorganic material-incorporated cation exchange membranes (CEMs) with improved properties have drawn attention for reverse electrodialysis (RED). This paper deals with improving CEMs properties by incorporating silica–magnetite inorganic materials from natural resources. First, silica and magnetite were extracted from rice husk and iron sand, respectively. CEMs were prepared using the phase inversion method by incorporating various ratios. The results showed that both silica and magnetite were in micron size with yields of 76.6% and 59.2% wt., respectively. The CEMs containing magnetite materials showed higher ion exchange capacity (IEC) and ionic conductivity than PVC membranes. However, they had a greater swelling degree. The presence of silica reduced the swelling degree from 18.38% to 7.15% leading to membrane strengthening. A maximum IEC and conductivity of CEMs of 0.26 meq/g and 0.524 S/cm were obtained for the membrane prepared with a SiO2/Fe3O4 ratio of 0:4, respectively. However, considering all aspects, the addition of a SiO2/Fe3O4 ratio of 1:3 was the most significant for increasing the fixed cation density and conductivity by 27.49% and 2815%, respectively, compared to other ratios. Thus, this SiO2/Fe3O4 ratio (1:3) should be considered for practical implementation. Performance examination using RED confirmed that the PVC/SiO2/Fe3O4 can be used as CEM for power generating and had comparable performance to commercial membrane.

Multivariate Polycrystalline Metal-Organic Framework Membranes for CO2/CH4 Separation.

Membrane technology is attractive for natural gas separation (removing CO2, H2O, and hydrocarbons from CH4) because of membranes' low energy consumption and small environmental footprint. Compared to polymeric membranes, microporous inorganic membranes such as silicoaluminophosphate-34 (SAPO-34) membrane can retain their separation performance under conditions close to industrial requirements. However, moisture and hydrocarbons in natural gas can be strongly adsorbed in the pores of those membranes, thereby reducing the membrane separation performance. Herein, we report the fabrication of a polycrystalline MIL-160 membrane on an Al2O3 substrate by in situ hydrothermal synthesis. The MIL-160 membrane with a thickness of ca. 3 μm shows a remarkable molecular sieving effect in gas separation. Besides, the pore size and environment of the MIL-160 membrane can be precisely controlled using reticular chemistry by regulating the size and functionality of the ligand. Interestingly, the more polar fluorine-functionalized multivariate MIL-160/CAU-10-F membrane exhibits a 10.7% increase in selectivity for CO2/CH4 separation and a 31.2% increase in CO2 permeance compared to those of the MIL-160 membrane. In addition, hydrophobic MIL-160 membranes and MIL-160/CAU-10-F membranes are more resistant to water vapor and hydrocarbons than the hydrophilic SAPO-34 membranes.

Salt storage and induced crystallisation in porous asymmetric inorganic membranes

Processing brines to recover strategic mineral salts using evaporation ponds requires large surface areas and are slow, even in arid climates. Here we show a novel membrane macropore storage mechanism that induces fast salt crystallisation in mesoporous top-layers in inorganic asymmetric membranes, stemming from 789 million nucleation points per metre square of surface area. During membrane pervaporation, dissolved salts are retained mainly in the macropores of the substrate which subsequently provide ideal conditions for crystal nucleation and growth on the membrane surface upon drying. This novel pore storage mechanism is attained owing to the solution flow modulation of the mesoporous titania and gamma-alumina layers that is counterbalanced by the flow of water during pervaporation. Therefore, pore size control is imperative to avoid flooding in the macroporous substrate. This work further shows the fundamental properties of the salt storage mechanism described by a single salt production coefficient, and a global salt production coefficient for metal chloride salts. This technology could potentially be considered for unlocking and process strategic global minerals from brines.

Artificial Intelligence based modeling of pervaporation process for alcohol dehydration

In this study, an Artificial Intelligence/artificial neural network (ANN) based approach is used to model the pervaporation process for alcohol dehydration using an inorganic membrane. The Deep Learning Toolbox of MATLAB was used to model an artificial neural network. ANN was developed with a single hidden layer and a variable number of neurons. Results showed that minimum Mean Squared Error was found with 12 neurons for permeate flux and 15 neurons for selectivity, and thus, the same number of neurons were considered for further simulations. Model predictions showed a good fit with experimental results with 0.96 and 0.98 correlation factors for permeate flux and selectivity, respectively, which provide confidence in the model predictions.Later, trained neural networks were used to study the effects of operating parameters. A maximum value of flux 5.8 kg/m2h was found at 90 °C feed temperature and 2.9 kPa permeate pressure. Similarly, the highest selectivity for water 1099 was found at 100 dm3/h flow rate and 0.96 kg/kg isopropanol concentration.

Dye Waste: A significant environmental hazard

Dyes are the substances that are used to impart color to textiles, fabrics, leather, or other materials. These are such colored substances that bond chemically to any substrate to which they are being applied. Any fabric’s attraction is its color. Regardless of how great its development is, if not colored as expected to be, it will fall flat as a business material. Therefore, the turn of events and utilization of manufactured colors for texture coloring has formed into a multibillion-dollar industry. In actual, humanity has known about the specialty of adding color to texture since 3500 BCE. They look attractive after coloring but their waste is toxic to the environment. Scientists, then again, are worried about their toxic nature. Engineered colors adversely affect all parts of life. Dyes have harmful effects upon water bodies as much waste from industries goes to rivers, lakes, etc. which ultimately causes water pollution. So, quick prevention measures need to be taken for saving the environment from dye waste. This paper likewise tells the classification and toxicity of some synthetic dyes and provides a brief idea about present methods for the removal of dyes from the environment which includes adsorption, chemical precipitation, inorganic materials usage, membrane filtration, and ion exchange. It also provides aspects affecting adsorption of color like arrangement pH, adsorbent portion, and temperature.

Dimethylimidazolium-Functionalized Polybenzimidazole and Its Organic-Inorganic Hybrid Membranes for Anion Exchange Membrane Fuel Cells.

A quaternized polybenzimidazole (PBI) membrane was synthesized by grafting a dimethylimidazolium end-capped side chain onto PBI. The organic–inorganic hybrid membrane of the quaternized PBI was prepared via a silane-induced crosslinking process with triethoxysilylpropyl dimethylimidazolium chloride. The chemical structure and membrane morphology were characterized using NMR, FTIR, TGA, SEM, EDX, AFM, SAXS, and XPS techniques. Compared with the pristine membrane of dimethylimidazolium-functionalized PBI, its hybrid membrane exhibited a lower swelling ratio, higher mechanical strength, and better oxidative stability. However, the morphology of hydrophilic/hydrophobic phase separation, which facilitates the ion transport along hydrophilic channels, only successfully developed in the pristine membrane. As a result, the hydroxide conductivity of the pristine membrane (5.02 × 10−2 S cm−1 at 80 °C) was measured higher than that of the hybrid membrane (2.22 × 10−2 S cm−1 at 80 °C). The hydroxide conductivity and tensile results suggested that both membranes had good alkaline stability in 2M KOH solution at 80 °C. Furthermore, the maximum power densities of the pristine and hybrid membranes of dimethylimidazolium-functionalized PBI reached 241 mW cm−2 and 152 mW cm−2 at 60 °C, respectively. The fuel cell performance result demonstrates that these two membranes are promising as AEMs for fuel cell applications.

Chitosan modified inorganic nanowires membranes for ultra-fast and efficient removal of Congo red

Chitosan modified hydrogen titanate nanowires membrane is prepared through a simple immersion-filtration method, which can be used to adsorb anionic dyes. The adsorption kinetics data shows that the adsorption process follows the pseudo-second-order model. Thermodynamics analysis reveals the adsorption is a spontaneous process. During the dynamic adsorption process, chitosan modified hydrogen titanate nanowires membrane shows excellent removal rate of 99.5% and adsorption capacity of 374.4 mg g−1 for Congo red. The membrane exhibits excellent cyclic adsorption performance and satisfactory removal rate in the pH range of 2.5–12.5. After 15 adsorption–desorption cycles, the removal rate and permeability of Congo red remain above 98.7% and 1120.0 L m-2h−1 bar−1, respectively.

Reactional Processes on Osmium-Polymeric Membranes for 5-Nitrobenzimidazole Reduction.

Membranes are associated with the efficient processes of separation, concentration and purification, but a very important aspect of them is the realization of a reaction process simultaneously with the separation process. From a practical point of view, chemical reactions have been introduced in most membrane systems: with on-liquid membranes, with inorganic membranes or with polymeric and/or composite membranes. This paper presents the obtaining of polymeric membranes containing metallic osmium obtained in situ. Cellulose acetate (CA), polysulfone (PSf) and polypropylene hollow fiber membranes (PPM) were used as support polymer membranes. The metallic osmium is obtained directly onto the considered membranes using a solution of osmium tetroxide (OsO4), dissolved in tert–butyl alcohol (t–Bu–OH) by reduction with molecular hydrogen. The composite osmium–polymer (Os–P)-obtained membranes were characterized in terms of the morphological and structural points of view: scanning electron microscopy (SEM), high-resolution SEM (HR–SEM), energy-dispersive spectroscopy analysis (EDAX), Fourier Transform Infra-Red (FTIR) spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The process performance was tested for reduction of 5–nitrobenzimidazole to 5–aminobenzimidazole with molecular hydrogen. The paper presents the main aspects of the possible mechanism of transformation of 5–nitrobenzimidazole to 5–aminobenzimidazole with hydrogen gas in the reaction system with osmium–polymer membrane (Os–P).

Mixed ionic-electronic conducting composite-based ceramic-carbonate dense membranes for CO2/O2 counter-permeation and CO oxidation

Dense inorganic membranes made of the ionic conductor Ce0.80Sm0.15Sr0.05O2-δ and the electronic-ionic conductor Sm0.6Sr0.4Al0.3Fe0.7O3-γ were infiltrated with molten carbonates. One side of the membrane is supplied with CO, and the opposite side is fed with O2. The CO oxidation and CO2/O2 counter-permeation fluxes are studied as functions of temperature and weight percent of the mixed ionic-electronic conductor phase. The O2 counter-permeation was correlated to the oxygen ionic flux counter-permeation consumed for CO oxidation and CO32− formation for CO2 permeation. The Ce0.80Sm0.15Sr0.05O2-δ/Sm0.6Sr0.4Al0.3Fe0.7O3-molten carbonates system exhibits higher oxygen ionic flux counter-permeation than Ce0.80Sm0.15Sr0.05O2-δ-molten carbonates system, producing a larger amount of CO conversion in the first case. The limiting factor for the O2 counter-permeation and CO2 permeation in triple-phase membranes is the oxygen ionic conductivity. In dual-phase membranes, the redox reaction for oxygen dissociation becomes vital for oxygen ionic flux. However, the limiting factor for the O2 permeation flux is the oxygen ionic transport in the ceramic phase. On other hand, the limiting factor for the CO2 permeation is attributed to both the ionic transport in the molten carbonates and the ceramic phase. The weight percent of the perovskite Sm0.6Sr0.4Al0.3Fe0.7O3 was varied to study the effect of its electronic property on the CO2/O2 counter-permeation flux and CO oxidation, establishing that the electronic nature of Sm0.6Sr0.4Al0.3Fe0.7O3 enhances the formation of oxygen ions. This increases the carbonate ions concentration on the surface of the CO-supply membrane side, which raises the driving force for CO2 permeation. Also, the CO2 formation rate on the oxygen supply side is faster than on the CO-supply membrane side. The formation rate of molecular oxygen is lower than the CO2 formation rate.

High Performance Hybrid Graphene Nano Filters as a Total dissolved solid remover

Graphene, a single-layer carbon sheet with its distinctive two-dimensional (2D) single-atomic-thick sp2 hybridized hexagonal packed lattice structure which is nearly friction less with high chemical inertness, and pliability which can be manufactured sustainably in great amounts with less expense, has shown many unique properties, Graphene has attracted tremendous research interest in recent years, owing to its exceptional properties. The scaled-up and reliable production of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (GO), offers a wide range of possibilities to produce nano-filters containing graphene membrane which is capable to remove ninety percent of the heavy contaminants from different sources of water and to reduce the level of total dissolved solids, salinity, and neutralizes the pH level further inorganic membrane used in synergism with graphene oxide shows improved efficiency and reduction in cost of production of separation membranes. In this review, we demonstrated real world application of graphene, Fabricated with Several Metal Oxides in synergism to illustrate enhanced photocatalysis properties, Flexural strength and anti-fouling characteristics of the material in comparisons to conventional membrane, photocatalytic metal oxides nanoparticles such as Titania TiO2, Zirconia ZrO2, Alumina Al2O3, and Silica SiO2 functions in the presence of Multiple Spectrums of Light by absorbing photons and releasing Oxygen Radical which degrades harmful water pollutants into less harmful substances.

SiC foam with a hollow skeleton and microporous strut wall used as a membrane contactor for the liquid-liquid extraction of Ce3+ and Pr3+

Membrane contactors have received considerable attention for extraction due to non-dispersive mass transfer through porous membranes. The past decades have seen the rapid development of organic hollow fiber membrane contactors, but very few studies have explored the applications of inorganic membranes in extraction, possibly due to their high costs. In this work, a novel SiC foam material with a hollow skeleton and microporous strut wall was used as a ceramic membrane contactor (HS-FCMC) for rare earths extraction. The foam's structure was characterized by scanning electron microscopy (SEM), X-ray micro-computed tomography (micro-CT), and mercury intrusion porosimetry (MIP). The flow and concentration fields inside and outside the foam cell were simulated by computational fluid dynamics (CFD), and the mass transfer through the ceramic membrane was analyzed. Based on the nitric acid–Ce3+/Pr3+–P507–kerosene chemical system, the extraction efficiency of Pr3+ and Ce3+ using the HS-FCMC reached 96.13% and 92.86%, respectively. A comparison study with poly tetra fluoroethylene (PTFE) hollow fibers was also conducted. The results indicate that the HS-FCMC is suitable for rare earths extraction due to the multiscale porous structure and chemical stability of the hollow-skeleton SiC foam. This research advances the knowledge of inorganic membrane extraction methods.

Evaluation of membrane-assisted hybrid processes for the separation of a tetrahydrofuran-methanol-water mixture

The combination of pervaporation (PV) and distillation provide considerable potential for the separation of azeotropic multicomponent mixtures. However, only a proper techno-economic evaluation of these processes compared to a reference process enables a reliable evaluation of benefits. Within this work, the potential of a PV-assisted distillation process is evaluated for the mixture of tetrahydrofuran methanol and water compared to a heat-integrated pressure-swing distillation process. Since initial evaluations reveal a significant potential of the PV-assisted processes regarding the required energy demand, experimental investigations of three polymeric and two inorganic membranes were conducted. A detailed characterization of the most promising membranes PERVAP™ 4155–40 and Hybrid Silica HybSi® AR was performed, and the latter one provided the highest permeance and selectivity. Based on the derived flux models, an economical optimization was performed. Despite the energy-benefits of the PV-assisted processes, the reference process was still evaluated more favorable under the considered framework, mainly caused by high investment and cooling costs. The current study illustrates the benefits of a tight integration of model-based process design and experimental investigations. Despite possible energy savings and promising performance metrics of the membrane, an assessment of the techno-economic performance of these processes is of major importance to identify applications.

Research progress and prospect of membrane method in seawater/brine extraction of lithium

With the widespread promotion of new energy electric vehicles for lithium batteries worldwide, the demand for lithium is surging. And the industry chain of lithium is in the process of technological transformation and upgrading, the extraction of lithium from salt lake brine is becoming the main source. Comprehensively compare the precipitation method, adsorption method, calcining leaching method, extraction method, and other processes used in the extraction of lithium from brine, membrane separation is a high-efficiency and energy-saving separation and purification technology without phase change at room temperature, and it has become the most promising energy-saving and environmentally-friendly new technology in the lithium extraction industry. At present, the research on membrane processes with lithium separation effect mainly includes membrane-adsorption, membrane-solvent extraction and membrane-electrodialysis, etc. And membrane-electrodialysis technology has been successfully applied to extract lithium from salt lake brine in industry. However, the existing shortcomings of organic membranes, such as membrane blockage, organic matter dissolution loss, and environmental pollution, limit the promotion of membrane-electrodialysis in the lithium extraction industry. Inorganic ceramic membranes are divided into microfiltration, ultrafiltration and nanofiltration according to the pore size. The separation process is mainly based on the “physical screening” theory, and the inorganic ceramic membrane material has stable chemical structure, good mechanical properties, simple preparation process, high temperature resistance, uniform pore size, It has many advantages such as narrow pore size distribution range and long life. Therefore, the development of new inorganic membrane materials has attracted widespread attention from the academic community and has become a hot issue in the study of lithium extraction by membrane methods.

Coordination Polymer Glasses with Lava and Healing Ability for High-Performance Gas Sieving.

Coordination polymer (CP) glasses offer a way to tackle the fabrication challenges encountered by inorganic porous membranes and show great potentials for size-exclusive gas separation. However, their processability and performance still cannot simultaneously meet the requirements for high-performance membrane separation. Herein, we have developed a series of CP glasses (M-P-dmbIm, M=Zn, Cd, Cu, and Mn), which possess low vitrification temperature as well as low viscosity (η) and lave capability above the transition temperatures. The derived glass (ag M-P-dmbIm) membranes show outstanding performances for H2 /CO2 , H2 /N2 , and H2 /CH4 separation, which all far surpass the Robeson upper bound and even rival against the best of the state-of-the-art gas separation membranes. The low viscosities not only allow us to hot-cast or hot-press the CP glasses into thin membranes within 5 min without sacrificing their selectivity and permeability, but also endow the resulted glass membranes with healing ability.

Coordination Polymer Glasses with Lava and Healing Ability for High‐Performance Gas Sieving

AbstractCoordination polymer (CP) glasses offer a way to tackle the fabrication challenges encountered by inorganic porous membranes and show great potentials for size‐exclusive gas separation. However, their processability and performance still cannot simultaneously meet the requirements for high‐performance membrane separation. Herein, we have developed a series of CP glasses (M‐P‐dmbIm, M=Zn, Cd, Cu, and Mn), which possess low vitrification temperature as well as low viscosity (η) and lave capability above the transition temperatures. The derived glass (agM‐P‐dmbIm) membranes show outstanding performances for H2/CO2, H2/N2, and H2/CH4 separation, which all far surpass the Robeson upper bound and even rival against the best of the state‐of‐the‐art gas separation membranes. The low viscosities not only allow us to hot‐cast or hot‐press the CP glasses into thin membranes within 5 min without sacrificing their selectivity and permeability, but also endow the resulted glass membranes with healing ability.

Separation of H2O/CO2 Mixtures by MFI Membranes: Experiment and Monte Carlo Study.

The separation of CO2 from gas streams is a central process to close the carbon cycle. Established amine scrubbing methods often require hot water vapour to desorb the previously stored CO2. In this work, the applicability of MFI membranes for H2O/CO2 separation is principally demonstrated by means of realistic adsorption isotherms computed by configurational-biased Monte Carlo (CBMC) simulations, then parameters such as temperatures, pressures and compositions were identified at which inorganic membranes with high selectivity can separate hot water vapour and thus make it available for recycling. Capillary condensation/adsorption by water in the microporous membranes used drastically reduces the transport and thus the CO2 permeance. Thus, separation factors of αH2O/CO2 = 6970 could be achieved at 70 °C and 1.8 bar feed pressure. Furthermore, the membranes were tested for stability against typical amines used in gas scrubbing processes. The preferred MFI membrane showed particularly high stability under application conditions.

The occurrence and dietary intake related to the presence of microplastics in drinking water in Saudi Arabia.

The implications and health effects of microplastics (MPs) ingestion are still unclear, yet researchers and organizations around the world are increasingly examining the levels of microplastics and nanoplastics in the environment. This study investigated the presence and the quantity of microplastics in bottled and tap water from five regions in Saudi Arabia and estimated the dietary intake of microplastics. Thirty samples of drinking water were collected from the retail markets in Saudi Arabia. The samples included plastic bottled drinking water, 2 glass bottles, and 2 samples of tap water to represent ground water and desalinated seawater. Sample preparation in the laboratory involved a vacuum-assisted filtration with an inorganic filter membrane (0.2-µm pore size). Identification and classification of microplastics particles using Fourier-transform infrared microspectroscopy (FTIR microspectroscopy). The particle size range screened for in this study was 25-500μm. Microplastics were identified in 17 out of 30 samples. The average of the detected microplastic particles was 1.9 pcs/L (lower bound estimate, LB) and 4.7 pcs/L (upper bound estimate, UB), respectively. The most frequently identified plastic type was polyethylene (PE), followed by polystyrene (PS), and polyethylene terephthalate (PET). Given an average recommended water intake of 3.7 and 2.7 L per day for men and women, respectively, the corresponding daily exposure to microplastics would result in 0.1-0.2 pcs/kg bw. The estimate for high water consumers increases to a daily exposure of 1.7-1.9 pcs/kg bw based on the recommended intake for water in hot weather by the WHO. From these results, we conclude that the level of dietary intake of microplastics from drinking water in Saudi Arabia is low, and according to current state of knowledge, microplastics from drinking water do not pose any concern to the consumers in Saudi Arabia.

Development of Fly Ash Coal/TiO2 Pored Composite Materials in The Making of Ceramic Membrane for Water Treatment Process

The ceramic membrane is a synthetic membrane, also called an inorganic membrane. The objectives of this study are to evaluate the characteristics of fly ash ceramic membrane and their performance for water treatment. The ceramic membrane fabrication process uses a printing process with a pressure of 1 atm with a burning temperature of 1100°C for 7 hours. The stages of this research include 1) composition optimization experiments with variations in the composition of fly ash and kaolin clay and temperature, 2) Characterization of ceramic membranes obtained by X-ray diffraction (XRD) and scanning electron microscope (SEM) tests. Optimization is carried out by varying the composition using a ratio of fly ash kaolin clay MB1: 40%: 20 %: 30%; MB2: 30%: 30%: 30%; MB3: 20%: 40%: 30% with a combustion temperature of 1100°C with a combustion process time of 7 hours. From the research results obtained, the porosity test results MB1 porosity 42%; The porosity of MB2 is 44%; The porosity MB3 is 50.22% from the porosity test results showing the higher composition of coal fly ash, the smaller porosity obtained. This phenomenon occurs during the combustion or sintering process to minimize the membrane pores. The structure of the membrane pores can be seen by the characterization test using SEM. SEM test results show that the MB1 ceramic membrane has delicate pores so that it has the potential to be applied. The experimental results showed that the utilization of fly ash for ceramic membrane material was promising for water treatment due to its excellent properties and filtration performance.

Catalytic Membrane Reactors: The Industrial Applications Perspective

Catalytic membrane reactors have been widely used in different production industries around the world. Applying a catalytic membrane reactor (CMR) reduces waste generation from a cleaner process perspective and reduces energy consumption in line with the process intensification strategy. A CMR combines a chemical or biochemical reaction with a membrane separation process in a single unit by improving the performance of the process in terms of conversion and selectivity. The core of the CMR is the membrane which can be polymeric or inorganic depending on the operating conditions of the catalytic process. Besides, the membrane can be inert or catalytically active. The number of studies devoted to applying CMR with higher membrane area per unit volume in multi-phase reactions remains very limited for both catalytic polymeric and inorganic membranes. The various bio-based catalytic membrane system is also used in a different commercial application. The opportunities and advantages offered by applying catalytic membrane reactors to multi-phase systems need to be further explored. In this review, the preparation and the application of inorganic membrane reactors in the different catalytic processes as water gas shift (WGS), Fisher Tropsch synthesis (FTS), selective CO oxidation (CO SeLox), and so on, have been discussed.