IN THIS RESEARCH, MIXED MATRIX MEMBRANES (MMMS) BASED ON MATRIMID AND POLY ETHER BLOCK AMIDE (PEBAX) POLYMERS WERE PREPARED AND THEIR PROPERTIES WERE INVESTIGATED. THE EXPERIMENTS RELATED TO THE PERMEATION OF MEMBRANES WERE PERFORMED AND RESULTS SHOWED THE ENHANCED GAS SEPARATION PROPERTIES OF THE MMMS COMPAIRING TO THE PRISTINE MEMBRANES. THE PERMEATION TESTS OF THE MEMBRANES WERE CARRIED OUT FOR BOTH PURE AND MIXED CO2/CH4 GASES. THE CHARACTERIZATION OF PERMEATE/RETENTATE GASES IN MIXED GASES SERIES OF MEMBRANE SEPARATION TESTS WAS PERFORMED USING A GAS CHROMOTOGRAPHY INSTRUMENT. STRUCTURAL CHARACTERIZATION OF THE MEMBRANES AND THEIR THRMAL BEHAVIOR WERE INVESTIGATED BY USING SEM, TGA AND THE RESULTS WERE DISCUSSED.

POLYMERIC MEMBRANES, DESPITE MANY ADVANTAGES, ARE SUFFERING FROM POOR WETTABILITY, THERMAL AND MECHANICAL INSTABILITY, SOLVENT RESISTANCE, ETC. THE DEFICIENCIES RESTRICT THE MEMBRANES APPLICATIONS IN MOST OFSEPARATION PROCESSES. SO FAR, SEVERAL METHODS HAVE BEEN PROPOSED TO CIRCUMVENT THE AFOREMENTIONEDDEFICIENCIES ACCORDING TO THE DESIRED PURPOSES.IN GENERAL, NANOMATERIALS CAN BE INCORPORATED INTO/ONTO A POLYMERIC MEMBRANES BY BLENDING WITH THE DOPE SOLUTION OR BY ATTACHING THEM TO OUTERMOST SURFACE OF THE MEMBRANE SURFACES VIA PHYSICAL OR CHEMICAL APPROACHES [1]. SURFACE TREATMENT OF MEMBRANES CAN BE PERFORMED BY PLASMA TREATMENT, SELF-ASSEMBLY OF ORGANIC OR INORGANIC COMPOUNDS, GRAFT POLYMERIZATION AND FILLERS ADDITION. INCORPORATION OF THE SECONDARY COMPOUND INTO/ONTO POLYMER MEMBRANECAN ENHANCE, FOR EXAMPLE, THE WETTABILITY, PERMEATION FLUX AND MECHANICAL STABILITY AND CONSEQUENTLY CAN CONFER DIFFERENT TRAITS TO THE MEMBRANE. THE RECENT EMERGENCE OF COLLOIDAL PARTICLES WITH NANOSIZED PORES HAS INITIATED NEW INVESTIGATIONS WITH A NUMBER OF NOTABLE ADVANCEMENTS [2]. ADDITION OF NANOPARTICLES ACCORDING TO THEIR INHERENT CHARACTERISTICS AND CONTENT OF FILLERS MIGHT IMPROVE THE POLYMERS’ CRUCIAL PROPERTIES SUCH AS TENSILE MODULUS, STRENGTH, STIFFNESS, ELECTRICAL CONDUCTIVITY, DIELECTRIC COEFFICIENT, SOLVENT AND HEAT RESISTANCE, WETTABILITY ETC. [3]. IF THE POLYMER MATRIX LACKS SUFFICIENT COMPATIBILITY WITH THE NANOPARTICLES, MIXING SHEAR STRESS ALONE CANNOT RESULT IN HOMOGENOUS DISPERSION OF THE NANOPARTICLES. THEREFORE, DEPENDING ON THE MATRIX–FILLER COMBINATION, THEIR COMPATIBILITY HAS TO BE ENHANCED BY THE SURFACE FUNCTIONALIZATION OF THE FILLERS WITH ORGANIC SURFACTANTS OR OTHER CHEMICAL AGENTS [3]. THIS STUDY INVESTIGATES THE EFFECTS OF SILICA SURFACE MODIFICATION WITH DIFFERENT CHEMICAL MOIETIES, AND THE EFFECT OF THE SURFACE FUNCTIONALITY ON THE BULK MODIFIED MEMBRANES PHYSICOCHEMICAL PROPERTIES.

MIXED MATRIX MEMBRANES (MMMS) ARE A NEW GENERATION OF MEMBRANES WHICH ARE PREPARED TO IMPROVE THE PERFORMANCE OF PRESENT POLYMERIC MEMBRANES. SOME INORGANIC FILLERS SUCH AS POROUS MOLECULAR SIEVE TYPE MATERIALS AND ZEOLITE TYPE ARE INCORPORATED WITHIN A POLYMERIC MATRIX TO IMPROVE THE RESULTANT MMMS SEPARATION PERFORMANCE. THE MATHEMATICAL TOOLS FOR PREDICTING THE SEPARATION PERFORMANCE OF MMMS POTENTIALLY CAN SAVE TIME AND MONEY OF CARRYING OUT EXPERIMENTS AND ASSIST THE MMMS STRUCTURAL DESIGN. OXYGEN AND NITROGEN PERMEABILITY’S THROUGH DISPERSED PHASE OF ZEOLITE 4A WERE PREDICTED WITH ABSOLUTE ERROR OF 5% AND 9%, RESPECTIVELY. THEN USING THE DIFFERENT MODELS OF MMMS PERMEABILITY PREDICTIONS SUCH AS MAXWELL, MODIFIED MAXWELL, PAL, FELSKE AND MODIFIED FELSKE, OXYGEN AND NITROGEN PERMEABILITY’S OF DIFFERENT ZEOLITE 4A - POLYVINYL ACETATE MMMS WERE PREDICTED. THE MAXIMUM ABSOLUTE RELATIVE ERROR OF 2.1% WAS FOUND FOR MODIFIED MAXWELL MODEL AND THE MINIMUM ONE WAS FOUND FOR THAT MODIFIED FELSKE MODEL AS 1.1 %.

SUPER CAPACITORS CAN BE A SUITABLE RESPONSE TO ACCRUING DEMAND TO THE CLEAN ENERGY TECHNOLOGY BECAUSE OF THEIR HIGHER ENERGY DENSITIES COMPARED TO CONVENTIONAL CAPACITORS AND THEIR HIGHER POWER DENSITIES AND CYCLE LIFE COMPARED TO BATTERIES [1]. THEREFORE, THERE ARE SEVERAL TRENDS TO FIND APPROPRIATE MATERIALS FOR MAKING SUPERCAPACITORS’ ELECTRODES, WHICH SHOULD ILLUSTRATE A REVERSIBLE BEHAVIOR AND NONZERO CURRENT. NANO COMPOSITES, A COMBINATION OF NANO-DIMENSIONAL PHASES WITH DISTINCT DIFFERENCES IN STRUCTURE, CHEMISTRY AND PROPERTIES, CAN BE THE GOOD CANDIDATE FOR THIS PURPOSE. IN THIS STUDY, WE HAVE PREPARED A NANOCOMPOSITE CONTAINING OF NANOSTRUCTURED NICKELOXIDE AND COBALT OXIDE IN SILICA MEDIA BY SOL-GEL METHOD [2]. NICKEL NITRATE, COBALT NITRATE AND TETRAETHYLORTHOSILICATE IN MOLAR RATIO OF NICKEL TO COBALT SALTS OF 0, 0.35, 0.5, 0.65 AND 1 WERE DISSOLVED IN A SOLUTIONS OF ACETYL ACETONE, ETHANOL AND ETHYLENE GLYCOL. ONE DROP OF CONCENTRATED NITRIC ACID WAS TO THE REACTION MIXTURE AS THE CATALYST OF PREPARATION OF NICKEL OXIDE AND COBALT OXIDE PRECURSOR. THEN, SOL WAS PREPARED BY PUTTING THE MIXTURE IN A 70OC OVEN FOR 10 HOURS. THEN THE REACTION MIXTURE TRANSFERRED TO AN ELECTRICAL FURNACE WHICH ITS TEMPERATURE WAS ROSE TO 550OC FOR 5 HOURS. THE PREPARED NANOCOMPOSITES HAVE DIFFERENT COLORS FROM PURPLE TO BLACK DEPENDS TO THE RATIO OF NICKEL OXIDE TO COBALT OXIDE RATIO. THE CRYSTAL STRUCTURE AND MORPHOLOGY OF THE PREPARED MATERIALS WERE CERTIFIED BY XRD, SEM AND TEM. THEN, THE CAPACITIVE BEHAVIOUR OF THE PREPARED NANOCOMPOSITES WAS STUDIED BY CYCLIC VOLTAMMETRY STUDIES USING A STANDARD THREE-ELECTRODE CONSISTING OF AN AG/AGCL REFERENCE ELECTRODE, A PLATINUM GRID AUXILIARY ELECTRODE AND A CARBON PASTE WORKING ELECTRODE CONTAINING OF GRAPHITE + THE NANOCOMPOSITES POWDER IN A SOLUTION OF 1 M KOH AND THE EFFECT OF CHEMICAL COMPOSITION OF MIXED OXIDE WAS INVESTIGATED.

THIS STUDY INVESTIGATES THE GAS SEPARATION PERFORMANCE OF MIXED MATRIX MEMBRANES BASED ON THE POLYSULFONE (PSF) WITH THE ADDITION OF SILICA NANOPARTICLES. THE PERMEABILITY AND SELECTIVITY OF N2, AR, CH4 AND H2 GASES WERE INVESTIGATED AT 6 BAR AND 25OC. THE MEMBRANES WERE PREPARED BY SOLUTION-CASTING METHOD. TWO DIFFERENT CONCENTRATIONS OF POLYMER IN THE CASTING SOLUTIONS (10 AND 15 WT.%) WITH TWO VALUES OF NANOSILICA CONTENTS (10 AND 20 WT.%) WERE CONSIDERED. THE OBTAINED RESULTS INDICATED THE INCREASE IN PERMEABILITY OF APPROXIMATELY ALL GASES, BUT ENHANCEMENT IN H2/N2, H2/CH4 AND CH4/N2 SELECTIVITY BY INCREASING THE AMOUNTS OF NON-PERMEABLE SILICA NANOPARTICLES IN THE MEMBRANES.

THIS PAPER CONSIDERS THE FABRICATION OF PES/MWCNTS MIXED MATRIX HOLLOW FIBER MEMBRANES. TWO TYPES OF HOLLOW FIBER WITH AND WITHOUT MWCNTS WERE FABRICATED TO INVESTIGATION OF THEIR MORPHOLOGY. RESULTS SHOWED THE APPEARANCE OF FINGER LIKE MACROVOIDS IN TOP LAYER OF HOLLOW FIBERS BY ADDITION OF 0.5% MWCNTS IN THE POLYMERIC SOLUTION. FURTHERMORE, THE DENS LAYER OF THEM BECOMES THINNER.