Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Quaternary Ammonium Functionalized Cellulose for Bromate Ion Removal: Structural Insights and Efficacy Evaluation(Wiley, 2025) Koseoglu, Ecem; Senver, Buse Aleyna; Recepoglu, Yasar Kemal; Arar, OzgurThis study evaluates the potential of quaternary ammonium-modified cellulose as a biosorbent for bromate (BrO3-) removal from aqueous solutions. Elemental analysis and scanning electron microscopy (SEM) characterized the elemental composition and microstructural features of the biosorbent, whereas Fourier-transform infrared (FTIR) spectroscopy elucidated its molecular structure. Experimental results revealed that BrO3- removal efficiency increased with the biosorbent dose, achieving approximately 58%, 78%, and 90% removal with 0.025, 0.05, and 0.2 g of sorbent, respectively. The removal was pH-dependent, with efficiencies of 25%, 45%, and 76% at pH 2, 4, and 10, respectively, and the optimal removal was within the pH range of 6-8. Kinetic studies demonstrated rapid sorption, achieving 91% removal within 3 min. The Langmuir sorption isotherm model provided an excellent fit to the experimental data (R 2 = 0.9987), indicating a maximum sorption capacity of 9.40 mg/g. Thermodynamic analyses confirmed a spontaneous and endothermic sorption process (triangle G degrees = -8.11 kJ/mol; triangle H degrees = +2.22 kJ/mol). Desorption studies showed >= 99.9% efficiency using 0.1-M H2SO4 and NaCl, with NaCl selected as the preferred regenerant to minimize acid consumption. The biosorbent retained over 90% removal efficiency across three regeneration cycles. These findings highlight the potential of quaternary ammonium-modified cellulose as a sustainable and efficient material for BrO3- removal from water systems.Article Advancements in Oil-Water Separation: the Role of Molybdenum and Tungsten Disulfide as Cutting-Edge 2D Nanomaterials(Elsevier, 2025) Recepoglu, Yasar Kemal; Goren, Ayseguel YagmurThis article reviews recent strides in synthesizing, functionalizing, and utilizing molybdenum disulfide (MoS2) and tungsten disulfide (WS2) nanomaterials owing to their exceptional wetting properties, which facilitate oilwater separation. Among various materials explored, they have also emerged as particularly promising candidates due to their high surface area, tunable surface chemistry, and unique layered structure. The twodimensional (2D) morphology offers abundant active sites, enhanced interaction with water molecules, and the ability to engineer surface wettability at the nanoscale, all of which are highly advantageous for efficient oilwater separation. Distinct separation mechanisms, performance benchmarks, and potential integration into practical separation setups were meticulously surveyed and analyzed. Furthermore, to elucidate the superiority of MoS2 and WS2 2D nanomaterials over alternative methodologies for oil-water separation, we comprehensively examined other techniques, including membrane processes, electrocoagulation, adsorption with modified materials, and biological methods. For instance, the high membrane, operational, and maintenance costs, scaling, fouling, expensive production steps, high energy consumption, and complex operations are significant limitations of other processes for oil-water separation. On the other hand, the MoS2 and WS2 nanomaterials provide sustainable and effective oil-water separation performance compared to other processes owing to their unique properties, such as superior reusability, high separation efficiency, excellent hydrophobicity (water-repelling) and oleophilicity (oil-attracting) features, significant chemical and thermal stability, and enhanced photocatalytic properties. This review showed that the oil-water separation efficiency of the MoS2 and WS2-based materials was 70-100 %. The highest oil-water separation efficiency of 100 % is observed using cellulose acetate -MoS2 fibrous sponge from a toluene-water mixture at a pH of 8. Nevertheless, while MoS2 and WS2 nanomaterials promise oil-water separation owing to their unique properties, their limitations, such as cost, scalability, environmental concerns, agglomeration, regeneration challenges, and potential toxicity, must be carefully addressed. Consequently, further research and development are necessary to overcome these hurdles and fully realize their potential in practical applications.Article Pvc/Pan-immobilized H2TiO3 Adsorbent: a Tailored Titanium-Based Lithium-Ion Sieve for High-Performance Lithium Recovery(Royal Soc Chemistry, 2025) Recepoglu, Yasar Kemal; Ipek, Onur; Yuksel, AsliThe increasing demand for lithium, driven by the rapid development of electric vehicles and energy storage systems, has created a pressing need for efficient and sustainable lithium recovery technologies. Conventional methods often face challenges related to selectivity, environmental impact, and scalability, necessitating the development of alternative materials. In this study, a polyvinyl chloride/polyacrylonitrile (PVC/PAN)-immobilized titanium-based lithium-ion sieve (HTO) was synthesized for lithium recovery from aqueous media, including geothermal brine. The objective was to obtain a selective, reusable, and mechanically stable adsorbent suitable for industrial-scale applications. The synthesized PVC/PAN-HTO composite was characterized by FT-IR, BET, XRD, and SEM techniques. Batch adsorption studies showed that the optimum lithium recovery occurred at pH 12, with efficiencies of 98.7% in model lithium solutions and 91.6% in geothermal water using a 4 g L-1 adsorbent dosage. Adsorption kinetics followed a pseudo-second-order model, and the Langmuir isotherm provided the best fit, indicating monolayer adsorption with a maximum capacity of 5.79 mg g-1. Thermodynamic analysis confirmed that the adsorption process is spontaneous and exothermic. Reusability tests demonstrated stable performance over three adsorption-desorption cycles, confirming the potential of PVC/PAN-HTO for practical lithium extraction applications.Article Advanced Adsorptive Removal of Dimethyl Phthalate From Water Using a Tertiary Amine-Functionalized Polymeric Resin: Insights Into Experimental Design and Statistical Analysis(Royal Soc Chemistry, 2025) Turekkan, Kubranur; Recepoglu, Yasar Kemal; Ova Ozcan, Duygu; Arar, OzgurThis study investigates the effective removal of dimethyl phthalate (DMP) from aqueous solutions using Purolite Macronet MN100, a polymer-based adsorbent containing tertiary amine functional groups. A series of batch experiments was performed to assess the influence of resin dosage and solution pH, while adsorption kinetics were analyzed to determine the optimal contact time and the underlying rate-limiting mechanism. Equilibrium data were interpreted using adsorption isotherm models, and thermodynamic parameters (Delta G degrees, Delta H degrees, and Delta S degrees) were calculated to evaluate the feasibility and spontaneity of the process. Additionally, the effect of common coexisting ions in wastewater (Na+, K+, Mn2+, Ca2+, Mg2+) on DMP removal was examined. The optimum removal efficiency (>97%) was achieved using 0.02 g of resin per 25 mL solution at pH 2-6, with equilibrium established within 300 minutes. The adsorption behavior was best described by the Langmuir isotherm, indicating monolayer adsorption with a maximum capacity of 463.37 mg g(-1). Mechanistic evaluation revealed that pi-pi interactions and hydrogen bonding were the dominant forces driving DMP adsorption. The presence of competing cations had minimal impact, demonstrating the adsorbent's strong selectivity toward DMP. Desorption studies showed complete DMP recovery using absolute ethanol (>99%), with >99% regeneration efficiency. Optimization using Central Composite Design (CCD) under Response Surface Methodology (RSM) produced a statistically robust model (R-2 = 0.98), consistent with the experimental results. Overall, Purolite MN100 proved to be a highly efficient, selective, and regenerable adsorbent suitable for DMP removal in wastewater treatment processes.Article Citation - WoS: 2Citation - Scopus: 1Cross-Linked Carboxymethyl Cellulose Biosorbent for Zinc Removal: a Sustainable Remediation of Heavy Metal-Polluted Waters(Springer Heidelberg, 2025) Celgan, Dilber; Karadag, Asiye; Karim, Barna Jalaluddin Mohammad; Recepoglu, Yasar Kemal; Arar, OzgurThis study focuses on the preparation and characterization of cross-linked carboxymethyl cellulose (CMC) biosorbent for efficient removal of Zn2(+) ions from aqueous solutions. The microstructural features of the biosorbent were examined using scanning electron microscopy (SEM), while elemental analysis was conducted using an elemental analyzer to determine carbon (C), hydrogen (H), nitrogen (N), and sulfur (S) content. Fourier transform infrared (FTIR) spectroscopy was employed to identify functional groups within the biosorbent. Sorption experiments revealed that increasing the biosorbent dose led to higher Zn2(+) removal rates until equilibrium was reached. The optimal pH for Zn2(+) removal was determined to be >= 5, attributed to the conversion of acetate group to its ionic form. Rapid kinetics were observed, with 99% removal achieved within 5 min. The biosorbent exhibited a maximum sorption capacity of 10.809 mg/g and a removal rate of 99% at pH 5. Desorption studies demonstrated efficient Zn2(+) recovery using 0.25 M HCl solution, with a total desorption rate exceeding 99%. The findings indicate the potential for cost-effective regeneration of the biosorbent using dilute acid solutions, enhancing its sustainability and practical applicability in water purification processes. Additionally, the biosorbent's selectivity for Zn2(+) ions over competing ions and its effectiveness in treating real water samples, including those containing Na+, K+, Ca2(+), and Mg2(+), highlight its suitability for practical water purification applications.Article Citation - WoS: 4Citation - Scopus: 4Sulfonated Cellulose: a Strategy for Effective Methylene Blue Sequestration(Amer Chemical Soc, 2025) Toy, Mustafa; Recepoglu, Yasar Kemal; Arar, OzgurThis study investigates the sulfonation modification of cellulose for the removal of methylene blue (MB) from aqueous solutions. The prepared biosorbent was characterized, and its sorption capacity, kinetics, and thermodynamics were systematically evaluated. Fourier-transform infrared (FTIR) spectroscopy analyzed structural modifications, while scanning electron microscopy (SEM) examined the surface properties. The optimal sorbent dosage was determined as 0.05 g. MB removal efficiency increased from 11% at pH 1 to 70% at pH 2, reaching 99% within the pH range of 3 to 7. Kinetic studies revealed rapid sorption, achieving 99% removal within 3 min. Among various isotherm models, the Langmuir model provided the best fit (R 2 = 0.9989), indicating monolayer sorption with a maximum capacity of 37.65 mg/g. Thermodynamic analysis showed negative Delta G degrees values, confirming a spontaneous sorption process, while an enthalpy change (Delta H degrees) of -33.5 kJ/mol indicated exothermic behavior. The entropy change (Delta S degrees) of -82.6 J mol-1<middle dot>K-1 suggested decreased disorder during sorption. Regeneration studies demonstrated that 0.2 M HCl combined with ethanol achieved the highest desorption efficiency, and after three cycles, the MB removal efficiency remained above 99%. The presence of -SO3 - groups played a crucial role in MB sorption via ion exchange and may also contribute through hydrogen bonding, thereby enhancing MB sorption. These findings highlight sulfonated cellulose as an efficient and regenerable biosorbent for MB removal, offering valuable insights into its sorption mechanisms.Article Citation - WoS: 7Citation - Scopus: 7Quaternary Ammonium-Modified Cellulose: a Sustainable Strategy for Purifying Aqueous Solutions Contaminated With Sunset Yellow Dye(Elsevier, 2025) Toprakcurumez, Halil; Recepoglu, Yasar Kemal; Arar, OzgurThis study showcases the remarkable efficacy of quaternary ammonium-modified cellulose as a highly sustainable biosorbent for removing Sunset Yellow (SY) dye from water. Detailed analysis was conducted using infrared (FTIR) spectroscopy for structural changes and Scanning Electron Microscopy (SEM) for morphological changes. A minimal yet highly effective dose of 0.05 g was identified through dedicated optimization experiments, achieving near-complete removal (99 %) of SY. The biosorbent demonstrated exceptional performance across a broad pH range (2-10), accomplishing remarkable removal within just 5 min. Langmuir modeling uncovered a monolayer sorption mechanism with a high maximum capacity (107.08 mg g- 1), and thermodynamic analysis affirmed the spontaneity and favorability of the sorption process. Noteworthy is the biosorbent's impressive regeneration capabilities (up to 95 %) using 1.0 M NaOH or HCl solutions and its sustained performance over three sorption-regeneration cycles, highlighting its exceptional stability and reusability. The modified cellulose exhibited remarkable resistance to common interfering ions (chloride, nitrate, and sulfate) at 10 and 100 mg L- 1 concentrations. These combined features position quaternary ammonium-modified cellulose as a promising, sustainable, and efficient option for dye wastewater treatment.