Hossam Tieama - Academia.edu (original) (raw)
Papers by Hossam Tieama
Frontiers in Chemistry
Modified cellulose acetate membranes with bentonite clay (CA/bent) and TiO2 nanoparticles (CA/TiO... more Modified cellulose acetate membranes with bentonite clay (CA/bent) and TiO2 nanoparticles (CA/TiO2) using the phase inversion method are successfully prepared and characterized. These Membranes are favored due to their high salt rejection properties and recyclability. The IR and EDX spectral data indicate the formation of modified membranes. The Scan Electron Microscope micrographs show that the modified membranes have smaller particle sizes with higher porosity than the neat membrane. The average pore diameter is 0.31 µm for neat cellulose acetate membrane (CA) and decreases to 0.1 µm for CA/0.05bent. All modified membranes exhibit tensile strengths and elongation percentages more than the neat membrane. The higher tensile strength and the maximum elongation% are 15.3 N/cm2 and 11.78%, respectively, for CA/0.05bent. The thermogravimetric analysis of modified membranes shows higher thermal stability than the neat membrane. The modified membranes exhibit enhanced wettability and hydr...
American Journal of Applied Chemistry, 2015
Novel polyvinyl chloride grafted poly (ethylene imine), PVC-g-PEI membranes have been successfull... more Novel polyvinyl chloride grafted poly (ethylene imine), PVC-g-PEI membranes have been successfully synthesized by solvent evaporation technique using THF/ethanol as a solvent mixture. PEI was incorporated into PVC in different portions to increase the weak hydrophilicity of PVC membranes and to enhance physicochemical membranes surface properties. Membranes preparation conditions of PVC-g-PEI and their applications for water desalination process were optimized and discussed in details. PVC-g-PEI membranes were characterized by FTIR, morphologically using SEM, thermally using TGA&DSC, and mechanically using universal testing machine. Poly (ethylene glycol), PEG was then added to PVC-g-PEI membranes as a pore forming additive to increase pores density area and improve efficiency of the permeation flux of membranes. Addition of PEG portions increased permeation flux of PVC-g-PEI membranes (452 L/D/M 2 513 L/D/M 2 and605 L/D/M 2) and salt rejection performance for mono membrane (33.5%, 30.8%and 27.4 %) for 3%, 2% and 1% NaCl solutions, respectively. Ion Exchange Capacity (IEC) for (PVC-g-PEI) membrane was 2.3 meq/gm and water uptake was 23%.All filtration experiments results were carried out at a trans-membrane pressure of 0.3 MPa at room temperature. The results showed that the permeate quality and quantity almost stable upon long run, thus PVC-g-PEI membranes can be used effectively for water treatment applications e.g. Nano-filtration and desalination.
Applied Biochemistry and Biotechnology, 2010
ρ-Benzoquinone-activated alginate beads were presented as a new carrier for affinity covalent imm... more ρ-Benzoquinone-activated alginate beads were presented as a new carrier for affinity covalent immobilization of glucoamylase enzyme. Evidences of alginate modification were extracted from FT-IR and thermal gravimetric analysis and supported by morphological changes recognized through SEM examination. Factors affecting the modification process such as ρ-benzoquinone (PBQ) concentration, reaction time, reaction temperature, reaction pH and finally alginate concentration, have been studied. Its influence on the amount of coupled PBQ was consequently correlated to the changes of the catalytic activity and the retained activity of immobilized enzyme, the main parameters judging the success of the immobilization process. The immobilized glucoamylase was found kept almost 80% of its native activity giving proof of non-significant substrate, starch, diffusion limitation. The proposed affinity covalent immobilizing technique would rank among the potential strategies for efficient immobilization of glucoamylase enzyme.
Today, membrane separation technologies are widely used in many areas of water and wastewater tre... more Today, membrane separation technologies are widely used in many areas of water and wastewater treatment. Membrane processes can be used to produce potable water from surface water, groundwater, brackish water, or seawater, or to treat industrial wastewaters before they are discharged or reused. Membrane separation systems have many advantages over traditional water or wastewater treatment processes, lower operating and maintenance costs in comparison to conventional systems consisting of coagulation, clarification, and aerobic and anaerobic treatments. • Membrane separation systems are easy to operate and the performance is more reliable. • Membrane systems give a compact and modular construction, which occupies less floor space in comparison to the conventional treatment systems. In this review, we will introduce fundamental concepts of the membrane and membrane-separation processes, such as membrane definition, membrane classification, membrane formation, module configuration, tra...
Egyptian Journal of Chemistry
Frontiers in Chemistry
Modified cellulose acetate membranes with bentonite clay (CA/bent) and TiO2 nanoparticles (CA/TiO... more Modified cellulose acetate membranes with bentonite clay (CA/bent) and TiO2 nanoparticles (CA/TiO2) using the phase inversion method are successfully prepared and characterized. These Membranes are favored due to their high salt rejection properties and recyclability. The IR and EDX spectral data indicate the formation of modified membranes. The Scan Electron Microscope micrographs show that the modified membranes have smaller particle sizes with higher porosity than the neat membrane. The average pore diameter is 0.31 µm for neat cellulose acetate membrane (CA) and decreases to 0.1 µm for CA/0.05bent. All modified membranes exhibit tensile strengths and elongation percentages more than the neat membrane. The higher tensile strength and the maximum elongation% are 15.3 N/cm2 and 11.78%, respectively, for CA/0.05bent. The thermogravimetric analysis of modified membranes shows higher thermal stability than the neat membrane. The modified membranes exhibit enhanced wettability and hydr...
American Journal of Applied Chemistry, 2015
Novel polyvinyl chloride grafted poly (ethylene imine), PVC-g-PEI membranes have been successfull... more Novel polyvinyl chloride grafted poly (ethylene imine), PVC-g-PEI membranes have been successfully synthesized by solvent evaporation technique using THF/ethanol as a solvent mixture. PEI was incorporated into PVC in different portions to increase the weak hydrophilicity of PVC membranes and to enhance physicochemical membranes surface properties. Membranes preparation conditions of PVC-g-PEI and their applications for water desalination process were optimized and discussed in details. PVC-g-PEI membranes were characterized by FTIR, morphologically using SEM, thermally using TGA&DSC, and mechanically using universal testing machine. Poly (ethylene glycol), PEG was then added to PVC-g-PEI membranes as a pore forming additive to increase pores density area and improve efficiency of the permeation flux of membranes. Addition of PEG portions increased permeation flux of PVC-g-PEI membranes (452 L/D/M 2 513 L/D/M 2 and605 L/D/M 2) and salt rejection performance for mono membrane (33.5%, 30.8%and 27.4 %) for 3%, 2% and 1% NaCl solutions, respectively. Ion Exchange Capacity (IEC) for (PVC-g-PEI) membrane was 2.3 meq/gm and water uptake was 23%.All filtration experiments results were carried out at a trans-membrane pressure of 0.3 MPa at room temperature. The results showed that the permeate quality and quantity almost stable upon long run, thus PVC-g-PEI membranes can be used effectively for water treatment applications e.g. Nano-filtration and desalination.
Applied Biochemistry and Biotechnology, 2010
ρ-Benzoquinone-activated alginate beads were presented as a new carrier for affinity covalent imm... more ρ-Benzoquinone-activated alginate beads were presented as a new carrier for affinity covalent immobilization of glucoamylase enzyme. Evidences of alginate modification were extracted from FT-IR and thermal gravimetric analysis and supported by morphological changes recognized through SEM examination. Factors affecting the modification process such as ρ-benzoquinone (PBQ) concentration, reaction time, reaction temperature, reaction pH and finally alginate concentration, have been studied. Its influence on the amount of coupled PBQ was consequently correlated to the changes of the catalytic activity and the retained activity of immobilized enzyme, the main parameters judging the success of the immobilization process. The immobilized glucoamylase was found kept almost 80% of its native activity giving proof of non-significant substrate, starch, diffusion limitation. The proposed affinity covalent immobilizing technique would rank among the potential strategies for efficient immobilization of glucoamylase enzyme.
Today, membrane separation technologies are widely used in many areas of water and wastewater tre... more Today, membrane separation technologies are widely used in many areas of water and wastewater treatment. Membrane processes can be used to produce potable water from surface water, groundwater, brackish water, or seawater, or to treat industrial wastewaters before they are discharged or reused. Membrane separation systems have many advantages over traditional water or wastewater treatment processes, lower operating and maintenance costs in comparison to conventional systems consisting of coagulation, clarification, and aerobic and anaerobic treatments. • Membrane separation systems are easy to operate and the performance is more reliable. • Membrane systems give a compact and modular construction, which occupies less floor space in comparison to the conventional treatment systems. In this review, we will introduce fundamental concepts of the membrane and membrane-separation processes, such as membrane definition, membrane classification, membrane formation, module configuration, tra...
Egyptian Journal of Chemistry