Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Author: search.filters.author.Kucuker, Mehmet AliStart date: 2024

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Now showing 1 - 5 of 5
  • Article
    Ormosil Hybrid Coatings as a Sustainable Antibiofouling Solution for Microalgae Cultivation in Tubular Photobioreactors
    (Elsevier Sci Ltd, 2026) Belen, Sema Nur; Ipsalali, Ozde; Gunes, Kaniye; Kucuker, Mehmet Ali; Cengiz, Ugur
    This study demonstrated the potential of citric acid-APTES (Ormosil) coatings as an effective antifouling strategy to reduce biofilm formation in tubular photobioreactors used for microalgae cultivation. Among the tested coatings, CApTES2.7 exhibited superhydrophilic behavior in air and superoleophobic behavior underwater, significantly reducing the adhesion of Chlorella vulgaris compared to uncoated glass surfaces. Light transmission experiments and microscopic analyses showed that biofilm accumulation on coated surfaces decreased by more than 50 %, maintaining optical clarity within the reactor. Thermodynamic, DLVO, and XDLVO modeling supported these findings, indicating lower adhesion energies for algal cells on Ormosil-coated surfaces, consistent with their experimental antifouling performance. The application of CApTES2.7 coating in tubular PBR systems resulted in a 54.5 % increase in light transmittance compared to uncoated systems, thereby improving the photonic environment available for microalgal growth. Additionally, no chemical cleaning was required between cultivation cycles in coated reactors, demonstrating potential for reducing operational costs and water consumption in large-scale systems. In conclusion, this study presents an environmentally friendly and sustainable approach to overcoming biofilm-induced light attenuation-one of the main bottlenecks in industrial photobioreactors. Ormosil-based coatings not only extend the service life of PBRs but also enhance the economic feasibility of microalgae-based bioprocesses for biofuel, bioplastics, and high-value biomolecule production.
  • Article
    Citation - Scopus: 1
    Life Cycle Assessment of Black Tea Production and Consumption in Turkiye: Insights From Waste Management Scenarios
    (Elsevier, 2025) Uctug, Fehmi Gorkem; Küçüker, Mehmet Ali; Ediger, Volkan S.; Kucuker, Mehmet Ali; Berk, Istemi; Inan, Ali; Tugcu, Melisa
    This study conducts a life cycle assessment (LCA) of tea production and consumption in T & uuml;rkiye, the world leader in per capita tea consumption. Aiming to identify environmental hotspots and propose sustainable solutions, a cradle-to-grave LCA was performed using CCaLC2 software, CML methodology, and the Ecoinvent 3.0 database. It covers cultivation, processing, transportation, and consumption stages, focusing on key environmental indicators like carbon footprint and acidification potential. The results reveal that consumption dominates the environmental footprint (91%) due to energy-intensive brewing methods. Cultivation and transportation contribute minimally (4% each). This highlights the need for promoting energy-efficient brewing practices and consumer adoption of renewable energy sources. The study also explores the environmental implications of different waste management strategies. Composting emerged as the most beneficial approach for reducing the carbon footprint and photochemical oxidants creation, while incineration might be preferable for other impact categories. This study underscores the importance of addressing energy consumption during tea brewing and encouraging renewable energy use among consumers. Additionally, it promotes composting as a crucial waste management strategy for a more sustainable tea value chain in T & uuml;rkiye. These findings offer valuable insights for policymakers, industry players, and tea drinkers to make informed decisions that minimize environmental impact.
  • Article
    Citation - WoS: 1
    Effect of Mechanical Pre-Treatment on the Recovery Potential of Rare-Earth Elements and Gold From Discarded Hard Disc Drives
    (Springer, 2024) Habibzadeh, Alireza; Kucuker, Mehmet Ali; Gokelma, Mertol
    The growing demand for rare-earth elements (REEs) and their limited availability have made REEs critical with high supply risk. E-waste, particularly waste electrical and electronic equipment (WEEE), offers a valuable secondary source. This study assesses the impact of mechanical pre-treatment on the recovery of REEs and gold from discarded hard disk drives (HDDs). We compared recovery efficiencies of REEs and Au using separation techniques, particle sizing, and chemical analyses between two pre-treatment methods: shredding and manual disassembly. Shredding, common in electronic waste processing, leads to oxidation and significant loss of critical raw materials (CRMs), while manual disassembly preserves clean, and non-oxidized NdFeB magnets for magnet-to-magnet recycling. Manually disassembled HDDs were directly analyzed to determine recyclable quantities of REEs and gold. Shredded HDDs underwent sieving, density, and magnetic separation, followed by demagnetization and chemical analysis. Results indicate shredding causes a 73.9% loss of REEs and a 43.8% loss of Au compared to manual disassembly, with increased oxidation due to finer particles. These findings suggest that while shredding is adequate for recovering ferrous and aluminum fractions, manual disassembly is essential for maximizing REE recovery.
  • Conference Object
    Energy Management in Organized Industrial Zones: Promoting the Green Energy Transition in Turkish Manufacturing Industry
    (Ieee, 2024) Ediger, Volkan S.; Kucuker, Mehmet Ali; Berk, Istemi; Inan, Ali; Uctug, Fehmi Gorkem
    Organized Industrial Zones (OIZ), which gained legal status by Law 4562 of 2000, played a significant role in Turkish industrialization policies, particularly in improving Small and Medium-sized Enterprises (SMEs). The energy management (EM) within OIZs is essential for Turkiye's green transition and 2053 net-zero pathway. Following the publication of a directive on OIZ's electricity market activities in 2006, enterprises can purchase electricity directly from OIZ management. Moreover, the Energy Efficiency Law No. 5627 of 2007 required OIZs to establish an energy management unit (EMU) to serve the participants with less than 1000 tons of oil equivalent (toe) energy consumption. EMUs provide OIZ management with a unique opportunity to enhance sustainable energy transition by increasing renewable energy production and improving the energy efficiency of participating enterprises. The primary goal of this research is to evaluate the effectiveness of energy management units in OIZs in encouraging energy efficiency and green energy transition in the Turkish manufacturing industry. As a case study, we examine EM in the Adana Haci Sabanci Organized Industrial Zone (Adana OIZ), which ranks third among OIZs regarding electricity consumption. We analyze data on electricity infrastructures, roof-top PVs, invoice settlements/offsets, energy efficiency investments, and GHG emissions between 2017 and 2023. Our preliminary findings suggest that EMU in the Adana OIZ makes a very important contribution to the green transition of industrial establishments and that regulatory changes over the last decades have had positive effects. The share of renewable energy in the total energy mix increased from 1.6% to 21.4% over six years, and there has been a noteworthy enhancement in energy efficiency, reaching 27% in 22 companies evaluated. The main policy implication of our findings is that the role of regulatory bodies and efficient energy management in OIZs will be critical in achieving Turkiye's net zero target of 2053.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Microstructural Investigation of Discarded Ndfeb Magnets After Low-Temperature Hydrogenation
    (Springer, 2024) Habibzadeh, Alireza; Kucuker, Mehmet Ali; Cakir, Oznur; Gokelma, Mertol
    Due to continuously increasing demand and limited resources of rare-earth elements (REEs), new solutions are being sought to overcome the supply risk of REEs. To mitigate the supply risk of REEs, much attention has recently been paid to recycling. Despite the more common recycling methods, including hydrometallurgical and pyrometallurgical processes, hydrogen processing of magnetic scrap (HPMS) is still in the development stage. Magnet-to-magnet recycling via hydrogenation of discarded NdFeB magnets provides a fine powder suitable for the production of new magnets from secondary sources. One of the crucial aspects of HPMS is the degree of recovery of the magnetic properties, as the yield efficiency can easily reach over 95%. The amount, morphology, and distribution of the Nd-rich phase are the key parameters to achieve the excellent performance of the magnet by isolating the matrix grain. Therefore, a better insight into the microstructure of the matrix grains and the Nd-rich phase before and after hydrogenation is essential. In this study, a low-temperature hydrogenation process in the range of room temperature to 400 degrees C was conducted as the first step to recycle NdFeB magnets from discarded hard disk drives (HDDs), and the hydrogenated powder was characterized by electron microscopy and X-ray diffraction. The results show that there are three different morphologies of the Nd-rich phase, which undergo two different transformations through oxidation and hydride formation. While at lower temperatures (below 250 degrees C) the degree of pulverization is higher and the experimental evidence of hydride formation is less clear, at higher temperatures the degree of pulverization decreases. The formation of neodymium hydride at higher temperatures prevents further oxidation of the Nd-rich phase due to its high stability.