Polysulfone Mixed Matrix Membranes Research Articles

Carbon Dioxide/Nitrogen Separation Through Oxygenated Carbon Nanotubes‐Containing Polysulfone Membranes

AbstractMultiwalled carbon nanotubes (MWCNTs)‐containing polysulfone (PSf) mixed matrix membranes (MMM) are prepared using phase inversion by immersion precipitation. MWCNT are functionalized with oxygen groups to allow the dispersion of the filler in the polymer solution. Membranes with 0, 1, 3 and 5% w/w MWCNTs in PSf are prepared. The addition of the filler changed the permeability of pure PSf. The best results are found for the 1 wt% membrane, with increase in CO2 permeability of 660% and ideal selectivity CO2/N2 of 547%. The MMM also exhibited good thermal stability for gas separation. DSC and SEM results revealed that the addition of 1wt% of the filler caused changes in chain arrangements and membrane morphology.

Pillared cloisite 15A as an enhancement filler in polysulfone mixed matrix membranes for CO2/N2 and O2/N2 gas separation

The Cloisite 15A (C‒15A), an organically modified montmorillonite clay, was further modified with iron (Fe) pillars. Mixed matrix membranes (MMMs) were fabricated by incorporating Fe pillared Cloisite 15A (P–C15A) at different loading percentage of 0.1–1.5 wt% within the polysulfone (PSf) matrix. Fabricated membranes were characterized using thermal studies (TGA and DSC) and scanning electron microscopy (SEM). The morphological studies of fabricated MMMs confirmed that the P–C15A was well embedded through the PSf matrix. To investigate the effect of P–C15A incorporation, MMMs were tested for their gas permeation behavior using pure CO2, N2, and O2 gases. The gas permeation of MMMs was increased with the increase in loading percentage of P–C15A, whereas the gas selectivity was maintained at par to that of neat PSf membrane until it diminished at 1.5 wt% percentage of P–C15A causing mineral agglomeration. PSf/P–C15A (1 wt%) MMMs exhibited 232% and 274% increase in CO2 and O2 gas permeability respectively, while showing minimal variation in the selectivity of O2/N2 and CO2/N2 compared to that of neat PSf membrane. Furthermore, the gas separation performance of neat and P–C15A incorporated MMMs were compared with the Robeson upper bound. The PSf/P–C15A (1 wt%) MMM shown to have CO2 permeability of 18.01 barrer with the CO2/N2 and O2/N2 gas pair selectivities of 4.95 and 18.34 respectively, which depicted closeness towards the Robeson upper bound.

Functionalized KIT-6/Polysulfone Mixed Matrix Membranes for Enhanced CO2/CH4 Gas Separation.

The development of mixed matrix membranes (MMMs) for effective gas separation has been gaining popularity in recent years. The current study aimed at the fabrication of MMMs incorporated with various loadings (0–4 wt%) of functionalized KIT-6 (NH2KIT-6) [KIT: Korea Advanced Institute of Science and Technology] for enhanced gas permeation and separation performance. NH2KIT-6 was characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and N2 adsorption–desorption analysis. The fabricated membranes were subjected to FESEM and FTIR analyses. The effect of NH2KIT-6 loading on the CO2 permeability and ideal CO2/CH4 selectivity of the fabricated membranes were investigated in gas permeation and separation studies. The successfulness of (3-Aminopropyl) triethoxysilane (APTES) functionalization on KIT-6 was confirmed by FTIR analysis. As observed from FESEM images, MMMs with no voids in the matrix were successfully fabricated at a low NH2KIT-6 loading of 0 to 2 wt%. The CO2 permeability and ideal CO2/CH4 selectivity increased when NH2KIT-6 loading was increased from 0 to 2 wt%. However, a further increase in NH2KIT-6 loading beyond 2 wt% led to a drop in ideal CO2/CH4 selectivity. In the current study, a significant increase of about 47% in ideal CO2/CH4 selectivity was achieved by incorporating optimum 2 wt% NH2KIT-6 into the MMMs.

A study of different concentrations of bio-silver nanoparticles in polysulfone mixed matrix membranes in water separation performance

Silver/silver oxide nanoparticles (AgNPs) is one of the most effective inorganic compounds that acts as an antibacterial agent against Escherichia coli (E. coli) bacteria. In this study, bio-silver or -silver oxide (bio-AgNPs) was synthesised from the seeds and peels of the Parkia speciosa (P. speciosa) plant, a green reducing agent. The seeds and peels were extracted separately via facile methods using a solution of silver nitrate (AgNO3). The seeds were soaked and peels mixed with the AgNO3 solution. The resulting bio-AgNPs were then incorporated into polysulfone (PSf) membranes at different weight percentages (0.1, 0.3, 0.5, and 1.0 wt%). The results showed that the PSf mixed matrix membrane (MMM) with 1.0 wt% of P. speciosa peel-derived bio-AgNPs (PP1.0) had the most optimum properties with a smaller crystallite size of 51.60 nm, an average diameter of finger-like cavities of 15.23 μm, the smallest mean pore size of 10.20 nm and the highest surface roughness of 39.90 nm. PP1.0 was also found to be highly hydrophilic since it had the lowest contact angle (63.30°) which was corroborated by the highest hydroxyl (−OH) peak (3454.21 cm−1) seen during Fourier-transform infrared (FTIR) spectroscopy analysis. PP1.0 also had the highest water permeation flux (327.73 L m−2 h−1), lowest rejection rate (67.21%), lowest bio-AgNP leaching after water filtration (1.56 μg/L) and the formation of a 16.34 mm2 antibacterial inhibition ring. This proved that PP1.0 had the potential to be applied as an antibacterial membrane for water separation.

Mixed matrix membranes containing aspartic acid functionalized graphene oxide for enhanced oil-water emulsion separation

Polysulfone (PS) mixed matrix membranes (MMMs) containing aspartic acid (AA) functionalized graphene oxide (fGO) with improved flux, oil rejection, and resistance to fouling were fabricated via phase inversion. The membranes hydrophilicity, morphology, porosity, and mechanical properties were analyzed and the impact of fGO loading on them was investigated using contact angle measurements, SEM, AFM, and dynamic mechanical analysis. The results revealed an increase in the membrane’s hydrophilicity, water permeability and oil rejection at very low fGO loadings, i.e., 0.05 – 0.2 wt.%, but no further enhancement was obtained at higher loadings, i.e., 0.4−0.8 wt.%. Water permeability increased by 97 % at 0.2 wt.% fGO membrane compared to pristine membrane and oil rejection reached 97.9 % upon filtration of 200 mL oil emulsion. Moreover, the MMM containing 0.2 wt.% fGO exhibited enhanced fouling resistances as demonstrated by slow flux decline and 90 % flux recovery after two cycles of fouling with bovine serum albumin (BSA).The results indicated that the carboxylic and amino groups introduced by AA functionalization were responsible for the enhanced hydrophilicity and fouling resistance. PS/fGO MMMs provided significant enhancement in performance, mechanical properties and fouling resistance at very low fGO concentration that does not affect the rheology of PS-fGO formulation and therefore requires no alteration to the commercial phase inversion process.

Improving the Selectivity of ZIF-8/Polysulfone-Mixed Matrix Membranes by Polydopamine Modification for H2/CO2 Separation.

Gas separation membranes are essential for the capture, storage, and utilization (CSU) of CO2, especially for H2/CO2separation. However, both glassy and rubbery polymer membranes lead a relatively poor selectivity for H2/CO2 separation because the differences in kinetic diameters of these gases are small. The present study establishing the mixed matrix membranes (MMMs) consist of a nano-sized zeolitic imidazolate frameworks (ZIF-8) blended with the polysulfone (PSf) asymmetric membranes. The gas transport properties (H2, CO2, N2, and CH4) of MMMs with a ZIF-8 loading up to 10 wt% were tested and showing significant improvement on permeance of the light gases (e.g., H2 and CO2). Moreover, the depositional polydopamine (PDA) layer further enhanced the ideal H2/CO2 selectivity, and the PDA-modified MMMs approach the Robeson upper bound of H2/CO2 separation membranes. Hence, the PDA post-modification strategy can effectively repair the defects of MMMs and improved the H2/CO2selectivity.

Synthesis, characterization, and gas separation performances of polysulfone and cellulose acetate-based mixed matrix membranes

ABSTRACT The combination of polymeric and inorganic fillers inside mixed matrix membranes (MMMs) becomes a hot research topic due to the gas permeability-selectivity trade-off in polymeric membranes. Until recently, the problem of voids hampers the real application of MMMs, hence deep understanding on polymer-particle compatibility is required. This study focuses on the synthesis and characterization of polysulfone and cellulose acetate-based MMMs that combined with ZIF-8 and TiO2 particles. ZIF-8 dispersed more uniform than TiO2. The crystallinity of MMMs was higher than pure polymeric membrane. In addition, micro voids in MMMs resulted a slight decrease in CO2/N2 selectivity (from 15 to 12).

Effect of surface-etched modification on halloysite nanotubes (HNTs) for polysulfone mixed matrix membrane in CO2/CH4 separation

Mixed matrix membranes (MMMs) were fabricated from a 25 wt% of polysulfone (PSf) with halloysite nanotubes (HNTs) selected as the inorganic filler. The incorporation of 1 wt% to 5 wt% of HNTs in the membrane is promising in improving the performance of the membrane for gas separation due to its barrier properties. HNTs was modified by surface-etched method before it is embedded into the membrane in order to reduce the interfacial defects as well as the agglomeration in the membrane. This study further investigated the improvement of the polymer-clay interface interaction, characterize the functional groups, structure and surface area of the newly modified clay and also mechanical properties of the membrane. From the FTIR spectra, it can be seen that the functional group of surface-etched HNTs reduced in intensities compared to the unmodified HNTs. There are no distinct changes in XRD pattern for both unmodified and modified HNTs and tensile strength shows an increment in MMMs embedded with modified clay compared to unmodified clays. The incorporation of surface-etched HNTs was able to improve the membrane properties to a desired membrane that can be applied in the CO2 and CH4 separation.

Evaluation of silica sodalite infused polysulfone mixed matrix membranes during H2/CO2 separation

Global warming and environmental degradation have stimulated the drive towards the capture of large point source carbon emissions and reducing high energy intensity of industrial processes. Mixed membranes infused with high porosity silica sodalite are potential useful for pre-combustion CO2 capture. However, development of high quality mixed matrix membranes is a challenge. In this study, silica sodalite (SSOD) infused polysulfone (PSF) membranes were developed and evaluated for pre-combustion CO2 capture. The SSOD was obtained via topotactic conversion of layered silicates; and the membrane was prepared using the phase inversion method. The physicochemical nature of the SSOD and the SSOD/PSF was checked using XRD, SEM, and N2 physisorption at 77 K. Single gas permeation used to check membrane quality. N2 physisorption shows that the SSOD possesses higher surface area of 56.56 m2/g and pore volume of 0.181 cm3/g, when compared to that of the hydrothermally-synthesized hydroxy sodalite (HSOD) crystals (surface area: 27.43 m2/g; pore volume: 0.084 cm3/g). The SSOD/PSF membrane is asymmetric with higher mechanical strength than the ordinary PSF. Loading the PSF with SSOD enhanced its H2 permeance from 4.9 × 10−7 mol/m2·s·Pa but with a decrease in H2/CO2 separation factor from 2.2 to 0.6. While the enhanced H2 permeance is attributed to the enhanced porosity of the SSOD, the ideal selectivity is low but still within the values reported in literature. Increasing the SSOD loading up to 10 wt% enhanced the quality and performance of the PSF membrane, displaying H2 permeance of 6.5 × 10−7 mol/m2·s·Pa and a separation factor of 1.1. Though results reported in this study are promising, a robust synthesis protocol that will further enhance both the H2 selectivity and H2 permeance of the membrane is required. Furthermore, more studies are required on the process optimization and techno-economic feasibility for pre-combustion CO2 capture.

Enhancement of CO2 permeation properties of polymeric membrane by incorporating metal organic framework

This research work focuses on the fabrication of mixed matrix membranes (MMMs) for the enhancement of CO2 removal from CH4. Zeolitic imidazolate framework (ZIF-8) with a framework of 0.34 nm pore size which favours CO2 adsorption is used as filler in this work. Different loadings of ZIF-8 filler were incorporated into polysulfone (PSf) polymer matrix. From the EDX mapping, the morphology of the ZIF-8/PSf MMMs has shown compatibility between the polymer and filler phases. The MMMs demonstrated an increment of 8°C in glass transition temperature, Tg compared to the pure PSf. Based on the permeation results, MMM loaded with 1 wt% of ZIF-8 showed the highest performance with CO2 and CH4 permeability of 33.12 Barrer and 0.85 Barrer respectively, and CO2/CH4 ideal selectivity of 38.8. The development of this new type of MMM has great potential to be utilized in CO2/CH4 separation process.

A favored CO2 separation over light gases using mixed matrix membrane comprising polysulfone/polyethylene glycol and graphene hydroxyl nanoparticles

A novel polysulfone (PSF) mixed matrix membrane blended by polyethylene glycol (5 and 10wt.%) was synthesized in which the graphene hydroxyl (G-OH) nanoparticles incorporated. Polyethelene glycol (PEG) as an affordable additive provides a proper CO2 affinity. Moreover, the G-OH nanoparticles was enhanced the CO2 permeability in MMMs through Lewis acid- base interaction between electron withdrawing oxygen of −OH and CO2. First, PSF membrane was modified via adding PEG. Obtained results were shown that the CO2 permeability increased significantly from 15.9 Barrer (for neat PSF) to 28.2 Barrer (for PSF/PEG (10wt%), while a fairly significant increase in CO2/CH4 selectivity (from 12.23 for neat PSF to 12.81 for PSF/PEG (10wt%) at the pressure of 2bar and temperature of 35°C. Second, the G-OH nanoparticles were incorporated (1, 2, 3, 4 and 5wt%) into the both PSF/PEG (5wt%) and PSF/PEG (10wt%) matrix to prepare the PSF/PEG/G-OH MMMs. Results showed the best CO2/CH4 selectivity was obtained at 5wt% loading of G-OH for both PSF/PEG (5wt%) and PSF/PEG (10wt%) were 20.94 and 22.39, respectively; at pressure of 8bar. The separation properties of membranes were also evaluated at higher feed pressure and the obtained results were discussed.

The influence of Fe doped TiO2 as inorganic additive on the properties of polysulfone ultrafitration membrane

Recent development of utrafiltration (UF) technology for the mixed matrix polymeric membranes plays an important role to improve membrane properties. In this paper, the effects of inorganic additives prepared by green synthesis route towards polysulfone (PSf) membrane performance at different concentrations of Fe-TiO 2 (1.0wt%, 3.0wt% and 5.0wt%) have been experimentally investigate d . The blended membranes were fabricated via phase inversion using PSf as based polymer, N-metyl-2-pyrrolidone (NMP) as solvent, distilled water as a non-solvent, polyethylene glycol (PEG) as pore performing agent and Fe doped TiO 2 nanomaterial as inorganic additive. The characterization and morphology of the polysulfone mixed matrix membranes were analyzed via scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle and porosity. The performances of the membrane were evaluated in terms of pure water flux (distilled water) and rejection (humic acid) by using membrane permeation testing unit. The results of microscopic images revealed that the membranes incorporated with Fe doped TiO 2 have the asymmetric structure while the number and length of finger-like pores at top layerslightly increased from 3.0 wt% to 5.0 wt%, indicating the effect of hydrophilicity. Furthermore, the increasing of Fe-TiO 2 percentages also increased the porosity of membrane, as well as rejection percentages and hydrophilicity of membrane.

Cu2O photocatalyst modified antifouling polysulfone mixed matrix membrane for ultrafiltration of protein and visible light driven photocatalytic pharmaceutical removal

This study explains synthesis, characterization of an effective and efficient mixed matrix polysulfone (PSF) ultrafiltration membrane modified with Cu2O photocatalyst, synthesized using electrodeposition method, for pharmaceutical removal. Cu2O photocatalyst, polyethylene glycol, and N-methyl-2-pyrrolidone were used as additive, pore former, and solvent, respectively in the phase inversion method. Characterization techniques, such as XRD, FTIR, FESEM, FESEM-EDX, and AFM were used to characterize the photocatalyst and blended membranes so as to analyze their structural and functional attributes. Further, the membranes were analyzed by using permeation techniques to analyze their flux profiles. Similarly, antifouling nature and hydrophilicity of the membranes were studied by permeating aqueous BSA solutions and measuring the static water contact angle (SWCA), respectively. The pharmaceutical removal studies were carried out using ibuprofen (IBP). The additive improves the membrane attributes, such as flux improved from 34.24 L m−2 h−1 to 179.54 L m−2 h−1 deciphering improved porosity and pore size distribution; SWCA decreased from 71.5° to 45.3° showing increase in the hydrophilicity of the membranes; BSA adsorption decreased from 56 µg cm−2 to 27 µg cm−2; and successful removal of IBP at 86% was achieved under visible light conditions with a removal rate of 32.63 × 10−3 min−1.

Development of a novel graphene oxide-blended polysulfone mixed matrix membrane with improved hydrophilicity and evaluation of nitrate removal from aqueous solutions

In this study, four types of mixed matrix membranes were fabricated using polysulfone (as the base polymer) and different contents of graphene oxide (GO) nanosheets (as modifier) through wet phase inversion method. Based on the amounts of GO (0, 0.5, 1, and 2 wt%), the synthesized membranes named as M1, M2, M3, and M4, respectively. The membranes characteristics were evaluated using FE-SEM, FT-IR, and water contact angle measurements. In addition, the performance of the prepared membranes was investigated in terms of basic parameters: filtrate water flux, nitrate removal efficiency, and antifouling properties. Results showed significant improvements of the characteristics of modified membranes with GO. Accordingly, the permeability and hydrophilicity were enhanced and water flux was considerably improved. At operating pressure of 4 bar and nitrate concentration of 110 mg/L, the removal efficiency for unmodified membrane (M1) was 15.5% and for modified M2, M3, and M4 membranes were 22.78%, 39.12%, and 41.37%, respectively. In addition, the results of flux recovery ratio (FRR) showed that the anti-fouling properties of the GO modified membranes were improved due to the increase in membrane surface hydrophilicity.

EVALUATION OF IRON OXIDE DECORATED ON GRAPHENE OXIDE (FE3O4/GO) NANOHYBRID INCORPORATED IN PSF MEMBRANE AT DIFFERENT MOLAR RATIOS FOR CONGO RED REJECTION

In this study, iron oxide decorated graphene oxide (Fe3O4/GO) with three different molar ratio of Fe decorated on GO nanoplates (Fe percentage: 5 wt%, 10wt%, 20 wt%) were synthesized. First, GO nanoplates were synthesized using natural graphite powder according to the Hummers method. Fe3O4/GO nanohybrid was then prepared by co-precipitation of FeCl3.6H2O and FeSO4.7H2O with GO in the presence of ammonia hydroxide (NH4OH). The nanohybrid was characterized using X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM). The polysulfone (PSf) mixed matrix membranes containing 0.4 wt% of the nanohybrid were prepared by phase inversion method. The effect of different molar ratio of Fe3O4/GO nanohybrid on the membrane morphology was examined by several approaches such as porosity & pore size analysis, contact angle, and Field Emission Scanning Electron Microscopy (FESEM) & Energy Dispersive X-Ray (EDX). The mixed-matrix membranes performance were evaluated by measuring the membrane permeate flux and Congo Red (CR) rejection. All the PSf-Fe3O4/GO mixed-matrix membrane showed enhanced hydrophilicity, permeate flux and CR rejection compared to the neat PSf membrane. Experiment showed that the PSf-Fe3O4/GO mixed-matrix membrane with 5 wt% of Fe decorated onto GO nanoplates was having the best performance with the highest permeate flux of 112.47 L/m2.h and the CR rejection of 97±2%.

Sequential Use of UV/H2O2—(PSF/TiO2/MWCNT) Mixed Matrix Membranes for Dye Removal in Water Purification: Membrane Permeation, Fouling, Rejection, and Decolorization

Abstract Performance of a hybrid ultraviolet/hydrogen peroxide (UV/H2O2)–mixed matrix membrane system for an azo dye, acid black 1 [AB1], removal in a water purification process was studied. Different mixed matrix membranes embedded with titanium dioxide (TiO2) nanoparticles, multi-walled carbon nanotubes (MWCNTs), and a mixture of them were fabricated by the phase inversion method. Mixed matrix membranes embedded with MWCNTs resulted in higher pure water flux, and mixed matrix membranes embedded with TiO2 showed lower flux declines in the presence of AB1. However, all the membranes exhibited very low total organic carbon (TOC) rejection and none of the mixed matrix membranes could decolorize the AB1 solution. UV/H2O2 pretreatment of the AB1 solution resulted in enhanced TOC rejection, decolorization, and enhanced antifouling membrane behavior. Combining UV/H2O2 with each type of polysulfone (PSF) mixed matrix membranes (PSF/TiO2, PSF/MWCNT, and PSF/TiO2/MWCNT) resulted in optimal performance in terms of ...

The incorporation of graphene oxide into polysulfone mixed matrix membrane for CO2/CH4 separation

Carbon dioxide (CO2) is often found as the main impurity in natural gas, where methane (CH4) is the major component. The presence of CO2 in natural gas leads to several problems such as reducing the energy content of natural gas and cause pipeline corrosion. Thus it must be removed to meet specifications (CO2 ≤ 2 mol%) before the gas can be delivered to the pipeline. In this work, hollow fiber mixed matrix membrane (MMM) were fabricated by embedding graphene oxide (GO) into a polysulfone (PSf) polymer matrix to improve membrane properties as well as its separation performance towards CO2/CH4 gas. The membrane properties were investigated for pristine membrane and mixed matrix membrane filled with filler loading of 0.25%. The synthesized GO and properties of fabricated membranes were characterized and studied using TEM, AFM, XRD, FTIR and SEM respectively. The permeance of pure gases and ideal selectivity of CO2/CH4 gas were determined using pure gas permeation experiment. GO has affinity towards CO2 gas. The nanosheet structure creates path for small molecule gas and restricted large molecule gas to pass through the membrane. The incorporation of GO in PSf polymer enhanced the permeance of CO 2 and CO2/CH4 separation from 64.47 to 86.80 GPU and from 19 to 25 respectively.

Polyamine functionalized graphene oxide polysulfone mixed matrix membranes with improved hydrophilicity and anti-fouling properties

Polyamine functionalized graphene oxide (fGO) based polysulfone mixed matrix membranes with enhanced hydrophilicity, permeability and antifouling properties were synthesized. The effect of chain length of the amine in fGO on the performance of the mixed matrix polysulfone membranes was studied using three different polyamines, ethylenediamine, diethylenetriamine, and triethylenetetramine. Synthesized membranes were characterized for water contact angle, tensile strength, SEM, AFM, EDS, overall porosity, water permeability, fouling resistance, etc. fGO based polysulfone membranes showed higher porosity and permeability, improved structural and mechanical properties, and better anti-fouling potential with high flux recovery after bovine serum albumin (BSA) filtration with little change in BSA rejection. Polysulfone membranes containing 1wt.% ethylenediamine functionalized graphene oxide and 5wt.% polyethylene glycol (PEG-600) additives, displayed remarkably high pure water flux of 170.5LMH/bar, a 3-fold increase over corresponding control membrane, in addition to substantially higher BSA rejection and higher normalized recovered flux after fouling.

The effect of functionalized carbon nano-fiber (CNF) on gas separation performance of polysulfone (PSf) membranes

By mixing functionalized carbon nanofibers as inorganic substances with polysulfone (PSF) membrane, an extraordinary ability to separate CO2 from CH4 as well as N2 from O2 was developed in this study. The series of amine-functionalized-CNFs (F-CNFs)/PSf mixed matrix membrane with various F-CNFs contents (0–1.5wt.%) was prepared by solution casting method. In this paper, characterizations such as; morphology and crystalline structure have been conducted in details to investigate the structures and properties of mixed matrix membranes. The effects of F-CNF loading on the gas separation (O2, N2, CO2 and CH4) performance of the MMMs were evaluated using laboratory-scale gas separation apparatus. The MMMs exhibited higher CO2 permeability and perm-selectivity of CO2/CH4 due to higher interaction of amine groups on F-CNFs with CO2 as compared with the neat PSf membrane. The permeation measurement showed the CO2 and O2 permeability of about 3.57 and 1.58 (GPU), and CO2/CH4 and O2/N2 selectivity of about 7.7, 3.5, respectively, were obtained for MMM with 0.5wt.% F-CNFs loading. As a result, the developed membranes can be efficient for separating CO2 from CH4. The N2 selectivity was increased with addition of 0.5wt.% F-CNFs in the PSf casting solution, and then decreased with higher loading.

Formulation of Mixed-Matrix Membrane (PSF/Zeolite) for CO<SUB>2</SUB>/N<SUB>2</SUB> Separation: Screening of Polymer Concentration

This research investigates the permeability of CO2 and N2 as well as selectivity of CO2 over N2 of polysulfone (PSF) mixed matrix membranes filled with zeolite 4&Aring particles. The membranes were prepared by solution-casting method and utilized to determine the permeation rates of N2 and CO2. It was characterized by FTIR and the gas separation performance was analysed by Design of Expert (DOE) method. FTIR result revealed the intensity of peak for sulfone S=O vibration at 1322 cm-1; it was related to O=S=O bound of polysulfone in the sample. The single concentration variable has low outcome, however the mixture concentration interaction was effectively to lead better selectivity of CO2 over N2. In terms of interaction between mixture concentrations, interaction between PSF and N-Methyl-2-pyrrolidone (NMP) has considerable effect on the permeability of CO2 with the highest F value of 0.46 membrane. NMP exhibited a high degree of polarity and hydrogen bonding which led to effect of selective skin and permeation rate. The model regression equations were developed as the potential use for screening the permeability of CO2 and N2 based on the deviation effect of polymer concentration.