Yazar "Nigiz, Filiz Ugur" seçeneğine göre listele

Listeleniyor 1 - 7 / 7
  • [ X ]
    Öğe
    Application of Response Surface Methodology for Optimization of Copper Removal Using a Novel Polymeric Adsorbent
    (Springer, 2022) Unugul, Tuba; Nigiz, Filiz Ugur; Bozbas, Seda Karayunlu
    Depending on the increase in the world population, the need for consumption and industrial resources is increasing day by day. In the wastewater caused by industrial production, a serious amount of heavy metals and water pollution caused by inorganic dyestuffs occur. In this study, graphene nanoplate/natural zeolite/sodium alginate bio-composite adsorbent was prepared and copper removal from wastewater by adsorption method was investigated. The characterization of the adsorbent was carried out by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction and Brunauer-Emmett-Teller. In addition to batch adsorption tests, isotherm, kinetic and thermodynamic studies, experimental optimization was carried out with experimental parameters determined by the surface response methodology. Four experimental parameters (adsorbent dosage, metal concentration, solution pH, and contact time) were evaluated in a versatile way to determine the efficiency of heavy metal adsorption. The highest copper removal was obtained as 92.9% and 91.4%, respectively, in the experimental and model study at the adsorbent dosage of 0.5 g, the solution pH of 4.5, and the copper concentration of 20 ppm. The parametric results was meet with the optimization results with an R-2 value of 0.9834. The three most commonly used adsorption isotherms at 25 degrees C were calculated. The high R-2 value was found to be 0.9834 for the Langmuir isotherm model. It was determined that the adsorption kinetics matched the pseudo-second-order kinetics.
  • [ X ]
    Öğe
    Electrospun Gum Arabic-Pvdf Based Adsorbent and Filter Production for Gray Water Treatment
    (Springer, 2025) Katirci, Aysenur; Kahraman, Seniyecan; Nigiz, Filiz Ugur
    Gray water is a major component of domestic wastewater, containing pollutants such as surfactants, dyes, oils, nitrates, and phosphates. Effective treatment of gray water is critical in terms of increasing water scarcity and sustainable water management. In this study, gum arabic (GA) was used as a low-cost, biocompatible, and functional additive to enhance the properties of polyvinylidene fluoride (PVDF) membranes. Electrospinning was employed to fabricate nanofiber membranes by incorporating GA into PVDF at different weight ratios (1-5 wt%). The membranes were characterized using SEM, FTIR, TGA, and DSC to assess morphological, chemical, and thermal properties. SEM analysis revealed uniform fiber distribution without pilling, and GA addition slightly reduced fiber diameters. Thermal analysis confirmed improved thermal stability and altered degradation behavior with GA. Results showed that the contact angle decreased with GA addition, indicating increased hydrophilicity. Tensile strength increased from 6 MPa to 12.5 MPa at 3 wt% GA. Adsorption experiments for methylene blue (MB), oil, microplastics (MP), and anionic surfactants (LAS) were optimized using response surface methodology (RSM). Filtration tests demonstrated rejection rates of 99% for MB, 87% for oil, and 100% for MP. LAS rejection efficiency increased from 26 to 67.63% at 2 wt% GA. However, adsorption performance remained limited. The results show that the developed PVDF/GA membranes have high potential in the filtration-based treatment of gray water and that this technology can be applied to similar types of wastewater.
  • [ X ]
    Öğe
    Evaluation of Halloysite Nanotube-Loaded Chitosan-Based Nanocomposite Membranes for Water Desalination by Pervaporation
    (Springer Int Publ Ag, 2022) Unugul, Tuba; Nigiz, Filiz Ugur
    In this study, halloysite nanotube (HNT)-loaded chitosan-based nanocomposite membranes were synthesized and used for pervaporative desalination of water. Structural and morphological properties of the nanocomposite membranes were investigated. The effects of the HNT content, feed temperature, and feed NaC1 concentration on the flux and salt rejection were investigated. As the HNT content was increased, the degree of swelling decreased. At all temperature values, higher than 99% of salt rejections were achieved. The flux value increased from 1.63 to 4.89 kg/m(2)h, when the HNT content increased from 0 to 20 wt% at 30 degrees C. While the highest salt rejection value was obtained as 99.90% using the 10 wt% HNT-loaded nanocomposite membrane, the highest flux value was obtained as 5.81 kg/m(2)h using the 20 wt% HNT-loaded membrane at 50 degrees C. The pervaporation desalination results showed that HNT simultaneously increased the swelling resistance and the separation capability of the chitosan membrane.
  • [ X ]
    Öğe
    Graphene oxide-sodium alginate membrane for seawater desalination through pervaporation
    (Elsevier, 2020) Nigiz, Filiz Ugur
    In this study, graphene oxide (GO) filled sodium alginate membranes were synthesized and used for pervaporative desalination studies. The morphological, structural, thermal, and mechanical properties of membranes were determined. In the desalination studies, the effect of temperature and GO content on the separation performance was investigated. The addition of GO improved both the mechanical and thermal properties of the membrane as well as the separation performance. Higher than 99.4% of total rejection values were achieved by all the membranes at all studied temperatures. The flux value gradually increased from 1.63 kg/m(2).h to 4.89 kg/m(2).h when the GO concentration in the matrix increased from 0 wt% to 2 wt%. The highest flux of 8.11 kg/m(2).h with a rejection of 99.41% was obtained at 60 degrees C by using 2 wt% of GO loaded alginate membrane. The highest rejection of 99.95% with a flux of 3.46 kg/m(2).h was achieved at 40 degrees C by using 1 wt% of GO filled alginate membrane.
  • [ X ]
    Öğe
    Improved Oil-Water Separation Performance of Polylactic Acid by Halloysite Nanotube Incorporation
    (2022) Nigiz, Filiz Ugur
    In this study, polylactic acid (PLA)-based nanocomposite membranes were prepared and used for the purification of simulated oil/water based wastewater. The lubricant oil (lubricating oil) was chosen as model oil. In order to increase the hydrophilicity of the membrane and improve its filtration performance, 0-20 wt.% of Halloysite nanotubes (HNT) were added into the PLA matrix. The effects of the HNT ratio on the oil/water swelling ratios (adsorption ratio), water flux, and oil rejection were determined. According to the results, optimal flux-oil rejection results were obtained with 5 wt.% of HNT incorporated nanocomposite membranes. The highest oil rejection of 94.9% was obtained using 5 wt.% of HNT incorporated membrane with a flux value of 1542.9 LMH.
  • [ X ]
    Öğe
    Preparation and Characterization an Active Carbon Adsorbent from Waste Mandarin Peel and Determination of Adsorption Behavior on Removal of Synthetic Dye Solutions
    (Springer International Publishing Ag, 2020) Unugul, Tuba; Nigiz, Filiz Ugur
    In this study, carbonized mandarin peel (CMP) was prepared and characterized and the adsorption behavior of the activated carbon for methylene blue (MB) and methyl orange (MO) removal was investigated. Adsorbent (CMP) was characterized by means of scanning electron microscopy (SEM-EDS), X-ray diffraction (XRD), thermo-gravimetric analyses (TGA), and Fourier transform infrared spectroscopy (FTIR). In the adsorption studies, the effects of initial dye concentration, solution pH, adsorbent dosage, and contact time on dye removal were investigated. In the same conditions, MB showed higher adsorption capacity than that of the MO. Therefore, the isotherms, kinetics, and thermo-dynamical adsorption studies were performed for MB. The appropriate adsorption isotherm for MB using CMP was determined as Langmuir isotherm. The kinetic values are well defined by the pseudo-second order kinetic model. The highest MB removal of 99.77% was obtained with CMP concentration of 5 g/L when the dye concentration was 5 mg/L at pH value of 6.9. After solvent regeneration, the adsorbent maintained 95.17% of its regeneration activity. The results show that CMP can be used as a low-cost and natural adsorbent to remove synthetic dye from the effluent of the textile wastewater.
  • [ X ]
    Öğe
    Selective Separation of Carbon Dioxide in Flue Gases with Metal Organic Framework Doped Polyether Block Amide Membrane
    (Springer Int Publ Ag, 2025) Nigiz, Filiz Ugur
    Carbon dioxide (CO2) is a polluting gas in the atmosphere that has a greenhouse effect and directly causes global warming. Carbon dioxide is produced from natural sources and industrial sources as a result of combustion. When carbon dioxide from these sources is not used correctly, it is released into the atmosphere and the concentration in the atmosphere increases. This change in the atmosphere causes global warming and climate change. Therefore, reducing carbon dioxide emissions in the atmosphere is vital. In this study, polyether block amide (PEBA, Pebax 1657) nonporous membranes were prepared and tested for the separation of carbon dioxide from simulated flue gas. In order to increase the carbon dioxide selectivity and permeability, a zirconium-based metal organic framework (MOF, MIL 140B) was prepared and incorporated into the matrix. The effect of MIL 140B additive was investigated in single and mixed gas separation experiments. Additionally, the effects of pressure and concentration on separation performance were studied. As a result, it was seen that the produced membrane had an excellent structure and the MIL 140B additive significantly increased both the mechanical properties (14.56 MPa) of the membrane and the separation performance. The highest separation result of was obtained as 77.2 CO2 selectivity and 93.5 Barrer carbon dioxide permeability with 4 wt. % MIL 140B doped membrane.