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The crystal structure of poly (vinylidene fluoride) (PVDF) and morphology of composite membranes prepared from mixture of PVDF, Polyvinylpyrrolidone (PVP) and Sodium Maghnite nanoclay has been investigated in this research work. Several analytical methods were used for the characterisation of synthesised membrane samples such as FTIR spectroscopy, X-ray diffraction (XRD), porosity and contact angle It was found the effect of adding of increasing amounts of Maghnite can improve the piezoelectric phase of PVDF. These is confirmed by the increase of the Beta crystal phase ratio. It was proved also that the synthetised membranes occurs different interaction with Serum Albovine protein by the increase of the fouling index fluxes for the membrane with reach content of Maghnite. Which confirm that the deposition effect of BSA in the membrane surface with high amounts of ß crystal structures. [ABSTRACT FROM AUTHOR]

The objective of this research is to manufacture new filter pellets based on polyacrylamide (PAM) activated carbon (GAC), iron oxide (Fe2O3), zinc oxide (ZnO) and kaolin and to evaluate their effectiveness in removing chromium and nickel from water. The synthesized filter pellets were characterized by FTIR, XRD and X-ray fluorescence. The XRF validation method would involve known amounts of chromium and nickel being retained by the filter pellets. the application of XRF gave precise measurements of the concentrations of Cr(VI) and Ni(II) fixed in the filter pellets. It was found that the values of the retention rates of Cr(VI) ions are higher in comparison with Ni(II) ions .The inclusion of inorganic additives influences the ability of filter pellets (FP) to retain Cr(VI) and Ni(II). FP2 (ZnO) showed reduced retention for both ions in comparison to FP1 (Fe2O3) and FP3 (Kaolin). FP3 (Kaolin) displayed better retention capacities for Cr(VI) and Ni(II) ions. The conductometric approach was also used to evaluate the retention of ions by the filter pellets. Comparing the conductivity of the feed solution with that of the filtered solution and the comparison between the different materials provided information on the most effective filter pellets for this purpose. [ABSTRACT FROM AUTHOR]

Matrix hybrid membranes, based on polyvinylidene fluoride (PVDF), poly (N-vinylpyrrolidone) (PVP), silica gel (SG) and zinc oxide (ZnO) were synthesized by phase inversion via immersion precipitation method. The characterization of membrane samples was performed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), optical microscopy, contact angle, porosity, mean pore size and water permeability measurements. The FTIR analysis showed the appearance of new bands attributed to the functional groups of SG and ZnO. The XRD analysis confirmed a modification in the structure of membranes. The prepared membranes were used for the removal of hexavalent chromium (Cr(VI)) from aqueous solution. Membrane filtration experiments show that the water permeability and Cr(VI) rejection ratios increase with increasing the weight ratio ZnO (%)/SG (%). The maximum values of the Cr(VI) rejection rate and water permeability were respectively 85% and 685 L/m2hbar for weight ratios (0.75% of ZnO/0.25% of SG). [ABSTRACT FROM AUTHOR]

Microalgae represent an important source of valuable bioproducts (such as food, nutraceuticals, antioxidants, and pigments) and biofuel. They grow spontaneously in surface water and represent a contaminant that has to be separated. There is thus an urgent need to develop technologies to harvest and refine them. Depending on the microalgae species, different biocompounds can be found and appropriate separation and purification methods must be refined and selected. In this work, microalgae harvested in the Hammam Boughrara dam, situated in Tlemcen (north‐west of Algeria), were used as source to recover and fractionate bio‐derived molecules using membrane‐assisted processes. This study identified a suitable strategy to fractionate biomolecules using ultrafiltration (UF) membranes. To maintain a stable permeate flux it was necessary to decrease the complexity of the solution prior to UF. This was achieved by separating triacylglycerols (TAGs) and pigments, after breaking cells, by solid–liquid–liquid extraction with a green solvent. The UF of the remaining aqueous phase permitted a recovery factor of 70% of the proteins and more than 85% of the carbohydrates in the retentate. The TAGs that were not recovered in the green solvent, and remained in the aqueous phase, were separated in the permeate with a purity of about 70% and a recovery factor of about 60%. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]