PubMed İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/397
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Article Citation - WoS: 19Citation - Scopus: 22The Impact of Organic Cotton Use and Consumer Habits in the Sustainability of Jean Production Using the LCA Approach(Springer Heidelberg, 2022-09-14) Fidan, Fatma Sener; Aydogan, Emel Kizilkaya; Uzal, Nigmet; Şener Fidan, Fatma; Kızılkaya Aydoğan, EmelDue to the rise in clothing consumption per person and growing consumer awareness of environmental issues with products, the textile industry must adopt new practices for improving sustainability. The current study thoroughly investigates the benefits of using organic cotton fiber instead of conventional cotton fiber. Because of the extensive use of natural resources in the production of cotton, the primary raw material for textiles, which accounts for the environmental effects of a pair of jeans, a life cycle assessment methodology was used to examine these effects in four different scenarios. The additional scenarios were chosen based on the user preferences for washing temperatures, drying methods, and the type of cotton fiber used in the product. The environmental impact categories of global warming potential, eutrophication potential terrestrial ecotoxicity potential, acidification potential, and freshwater ecotoxicity potential were analyzed by the CML-IA method. The life cycle assessment results revealed that the lowest environmental impacts were obtained for scenario 4 with 100% organic cotton fiber with an improvement of 87% in terrestrial ecotoxicity potential and 59% in freshwater ecotoxicity potential. All of the selected environmental impacts of a pair of jeans are reduced in all scenarios when organic cotton is used. Additionally, consumer habits had a significant impact on all impact categories. Using a drying machine instead of a line dryer during the use phase is just as important as the washing temperature. The environmental impact hotspots for a pair of jeans were revealed to be the eutrophication potential, acidification potential, and global warming potential categories during the use phase, and the terrestrial ecotoxicity potential and freshwater ecotoxicity potential categories during the fabric manufacturing including cotton cultivation. The use of organic cotton as a raw material in manufacturing processes, as well as consumer preferences for washing temperature and drying methods, appears to have significant environmental impacts on a pair of jeans' further sustainable life cycle.Article Citation - WoS: 57Citation - Scopus: 73Removal of Heavy Metals from Aluminum Anodic Oxidation Wastewaters by Membrane Filtration(Springer Heidelberg, 2018-05-27) Ates, Nuray; Uzal, NigmetAluminum manufacturing has been reported as one of the largest industries and wastewater produced from the aluminum industry may cause significant environmental problems due to variable pH, high heavy metal concentration, conductivity, and organic load. The management of this wastewater with a high pollution load is of great importance for practitioners in the aluminum sector. There are hardly any studies available on membrane treatment of wastewater originated from anodic oxidation. The aim of this study is to evaluate the best treatment and reuse alternative for aluminum industry wastewater using membrane filtration. Additionally, the performance of chemical precipitation, which is the existing treatment used in the aluminum facility, was also compared with membrane filtration. Wastewater originated from anodic oxidation coating process of an aluminum profile manufacturing facility in Kayseri (Turkey) was used in the experiments. The characterization of raw wastewater was in very low pH (e.g., 3) with high aluminum concentration and conductivity values. Membrane experiments were carried out with ultrafiltration (PTUF), nanofiltration (NF270), and reverse osmosis (SW30) membranes with MWCO 5000, 200-400, and 100 Da, respectively. For the chemical precipitation experiments, FeCl3 and FeSO4 chemicals presented lower removal performances for aluminum and chromium, which were below 35% at ambient wastewater pH 3. The membrane filtration experimental results show that, both NF and RO membranes tested could effectively remove aluminum, total chromium and nickel (> 90%) from the aluminum production wastewater. The RO (SW30) membrane showed a slightly higher performance at 20 bar operating pressure in terms of conductivity removal values (90%) than the NF 270 membrane (87%). Although similar removal performances were observed for heavy metals and conductivity by NF270 and SW30, significantly higher fluxes were obtained in NF270 membrane filtration at any pressure that there were more than three times the flux values in SW30 membrane filtration. Due to the lower heavy metal (< 65%) and conductivity (< 30%) removal performances of UF membrane, it could be evaluated as pretreatment followed by NF filtration to protect and extend NF membrane life. The water treated by both NF and RO could be recycled back into the process to be reused with economic and environmental benefits.Article Citation - WoS: 15Citation - Scopus: 14Removal of Pesticides From Secondary Treated Urban Wastewater by Reverse Osmosis(Springer Heidelberg, 2022-04-11) Ates, Nuray; Uzal, Nigmet; Yetis, Ulku; Dilek, Filiz B.The residues of pesticides that reach water resources from agricultural activities in several ways contaminate drinking water resources and threaten aquatic life. This study aimed to investigate the performance of three reverse osmosis (RO) membranes (BW30-LE, SW30-XLE, and GE-AD) in rejecting four different pesticides (tributyl phosphate, flutriafol, dicofol, and irgarol) from secondary treated urban wastewater and also to elucidate the mechanisms underlying the rejection of these pesticides. RO experiments were conducted using pesticide-spiked wastewater samples under 10 and 20 bar transmembrane pressures (TMP) and membrane performances were evaluated. Overall, all the membranes tested exhibited over 95% rejection performances for all pesticides at both TMPs. The highest rejections for tributyl phosphate (99.0%) and irgarol (98.3%) were obtained with the BW30-LE membrane, while for flutriafol (99.9%) and dicofol (99.1%) with the GE-AD membrane. The increase in TMP from 10 to 20 bar did not significantly affect the rejections of all pesticides. The rejection performances of RO membranes were found to be governed by projection area as well as molecular weight and hydrophobicity/hydrophilicity of pesticides. Among the membranes tested, the SW30-XLE membrane was the most prone to fouling due to the higher roughness.Article Citation - WoS: 60Citation - Scopus: 66Preparation and Characterization of PSF/PEI Nanocomposite Membranes for Oil/Water Separation(Springer Heidelberg, 2018-06-26) Saki, Seda; Uzal, NigmetUltrafiltration (UF) is one of the significant advanced processes for oily wastewater treatment due to its clear advantages, for instance, ease in operation and efficient separation. The main drawback of these processes is the fouling problem and many researchers' effort on fabrication of high-performance membranes with higher hydrophilicity and antifouling properties. In this study, flat-sheet polysulfone (PSF)/polyethylenimine (PEI)/CaCO3 nanocomposite membranes were prepared by phase inversion method for oil/water emulsion separation. Structural properties of membranes were characterized by SEM, FT-IR, contact angle, tensile strength, and atomic force microscopy analysis. Increasing the CaCO3 nanoparticle loading exhibited the increased the water flux and BSA rejection. PSF/PEI/10 wt% CaCO3 nanocomposite membranes have 145 L/m(2) h water flux at 2 bar with a contact angle of 84 degrees and with 92% BSA rejection. All prepared CaCO3 nanocomposite membranes reached similar oil rejections at above 90%. Besides the higher water flux and oil removal efficiencies, 10 wt% of CaCO3 nanoparticle-blended PSF membranes has notable antifouling capacity with the highest flux recovery ratio (FRR) and lowest flux decay ratio (DR) values. The results showed that there is a great potential to use PSF/PEI/CaCO3 nanocomposite membranes for the treatment of oil water emulsions with higher permeability and antifouling capacity.