Sürdürülebilir Kalkınma Amaçları

  • MakaleAçık Erişim2026
    Removal of Pb(II) ions from aqueous solutions by Brevibacillus agri-loaded clay: Kinetic, isotherm, and artificial neural network modeling

    Belduz, Ali Osman; Inan, Kadriye; Duran, Celal; Ozdes, Duygu; Ozeken, Sengul Tugba; Nalçaoğlu, Aleyna; Şeker, Serdal

    In this study, a novel and efficient adsorbent was developed by immobilizing inactivated Brevibacillus agri biomass onto an abundant natural clay via a simple synthesis route for Pb(II) removal from aqueous media. The adsorption behavior of inactivated Brevibacillus agri-loaded clay (BLC) was evaluated using batch experiments by investigating the effects of initial solution pH (2.0–6.0), BLC dosage (0.5–4.0 g/L), contact time (1–180 min), initial Pb(II) concentration (10–420 mg/L), temperature (25–80°C), and the presence of foreign ions. The optimum conditions were determined to be an initial solution pH of 5.0 and a contact time of 120 min. Isotherm models were applied to elucidate the interactions between Pb(II) ions and BLC, while kinetic studies were conducted to evaluate the adsorption performance and underlying mechanisms. The maximum adsorption capacity of BLC was determined as 65.4 mg/g according to the Langmuir isotherm model. Thermodynamic parameters revealed that Pb(II) adsorption on BLC was exothermic, feasible, and spontaneous at 25ºC. Artificial neural network (ANN) studies provided highly accurate predictions by modeling and confirmed the reliability and applicability of the model for Pb(II) removal in industrial applications. This study presents an innovative and sustainable approach for heavy metal removal, offering an effective solution applicable to environmental remediation processes.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleYalnız künye2025
    Kinetics and Isotherm Evaluation for Adsorptive Removal of Anionic and Cationic Dyes from Aqueous Media by Sulfuric Acid-Modified Beech Sawdust

    Ozdes, Duygu; Ozeken, Sengul Tugba; Top, Yener; Kalkisim, Ozgun; Duran, Celal

    A novel and efficient adsorbent was prepared by modifying Fagus orientalis L. (beech) sawdust with H2SO4. The adsorption behavior of H2SO4-modified beech sawdust (SMBS) was investigated by batch experiments to offer a straightforward, inexpensive, and effective method for the retention of anionic and cationic model dyes, indigo carmine (IC) and methylene blue (MB), from wastewater. The experimental conditions were optimized by investigating the effects of the initial pH, initial concentrations of IC and MB dyes, dosage of SMBS, period of the contact, and the presence of salts in the aqueous media on the adsorptive performance of SMBS. The initial pH values of the aqueous solutions, from which IC and MB dyes will be removed, were optimized as 2.0 and 6.5 (natural), respectively. The optimum contact time for the adsorption of both dyes onto SMBS was determined to be 240 min. The mechanisms in the adsorption of IC and MB onto SMBS were investigated by evaluating the experimental data through different isotherm and kinetic models. The Langmuir isotherm model and pseudo-second order kinetic model performed well in explaining the mechanism of adsorption. Langmuir monolayer adsorption capacity of SMBS adsorbent was 38.85 mg g−1 for IC and 58.82 mg g−1 for MB. As a result, CMCP exhibited excellent performance in adsorbing organic pollutants, providing a low-cost and easily prepared alternative to other adsorbents found in the literature.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleAçık Erişim2025
    Insight into the adsorptive removal of Cr(VI) ions and 4-chlorophenol from aqueous media on cationic surfactant-modified cucumber peels

    Ozeken, Sengul Tugba; Ozdes, Duygu; Duran, Celal

    A new and cost-effective adsorbent material was developed by chemical modification of cucumber peels (CP) with a cationic surfactant, cetyltrimethylammonium bromide (CTAB). The adsorptive behavior of CTAB-modified cucumber peels (CMCP) was investigated in the retention of an organic pollutant (4-chlorophenol) and an inorganic pollutant (Cr(VI)) through batch experiments. The adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR) analysis and scanning electron microscopy (SEM) technique. Influences of initial concentrations of both pollutants, dosage of CMCP, initial solution pH, contact time, and foreign ions were parameters used to specify the optimized conditions. Results of the experiments were evaluated by three kinetic models, namely pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, to find out the dominant mechanisms in the retention of 4-chlorophenol and Cr(VI). Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models were applied to the adsorption data to estimate the adsorption capacity of CMCP and to describe the interactions between the species. Langmuir isotherm model fitted the data well, and the maximum Cr(VI) and 4-chlorophenol adsorption capacities of CMCP were 84.03 mg g−1 and 107.5 mg g−1, respectively. Consequently, CMCP demonstrated outstanding performance in the adsorption of both inorganic and organic pollutants, offering a low-cost, easily prepared alternative to other adsorbents reported in the literature.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleAçık Erişim2025
    Sol–Gel Synthesized CuFe2O4-Modified Biochar Derived from Tea Waste for Efficient Ni(II) Removal: Adsorption, Regeneration, and ANN Modeling

    Duran, Celal; Ozeken, Sengul Tugba; Seker, Serdal; Ozdes, Duygu

    In the present research, a novel magnetic adsorbent was developed via the sol–gel method by coating CuFe2O4 nanoparticles on biochar sourced from brewed tea waste. The synthesized adsorbent was utilized for the removal of Ni(II) ions from aqueous media. The adsorption efficiency of Ni(II) ions was assessed under crucial experimental conditions such as initial solution pH, contact time, adsorbent dosage, and initial Ni(II) concentration. The adsorbent exhibited rapid adsorption kinetics, achieving equilibrium in approximately 15 min, and maintained high efficiency across a wide pH range. Adsorption experiments were conducted for Ni(II) solutions at their natural pH (5.6) to minimize chemical usage and enhance process simplicity. An impressive maximum adsorption capacity of 232.6 mg g−1 was recorded, outperforming many previously reported adsorbents. Furthermore, desorption studies demonstrated nearly 100% recovery of Ni(II) ions using 1.0 M HCl solution, indicating excellent regeneration potential of the adsorbent. Additionally, the prediction performance of an artificial neural network (ANN) model was evaluated to predict Ni(II) removal efficiency based on experimental variables, showing strong agreement with experimental data. Isotherm and kinetic models were also applied to the data to estimate the adsorption mechanisms. These findings demonstrate the promise of CuFe2O4-modified tea waste biochar for sustainable water treatment applications.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleYalnız künye2024
    Adsorption of Azocarmine G dye on H2SO4-modified acacia sawdust

    Duran, Celal; Ozeken, Sengul Tugba; Camoglu, Aslihan Yilmaz; Ozdes, Duygu

    Presence of hazardous dyes in water cause considerable risks to the human health and environment due to their potential toxicity and ecological disruptions. Therefore, in the present research, to suggest an alternative method for the retention of toxic Azocarmine G (ACG) dye from aqueous media, natural and H2SO4-modified acacia sawdust were performed for the first time as low-cost and efficient adsorbents. Based on batch experiments, it was determined that the best conditions for the developed dye retention process were an initial pH of 2.0 and an equilibrium time of 240 min. Analysis of the data using both pseudo-first order and pseudo-second order kinetic models showed that the retention of ACG onto the adsorbents predominantly occurred through chemical adsorption. Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were employed to provide insights into the interaction between the adsorbate and adsorbent and the mechanism of the adsorption process. Maximum monolayer adsorption capacities of natural and H2SO4-modified acacia sawdust were determined as 28.01 and 64.90 mg g-1, respectively by Langmuir isotherm model. Results of the study clearly indicated that the modification of acacia sawdust with H2SO4 leads to a substantial increase in the adsorption performance of anionic dyes.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleAçık Erişim2023
    Natural and H2SO4 modified plane sawdust as a low-cost adsorbent: Removal of anionic and cationic dyes from aqueous solutions

    Duran, Celal; Kalkışım, Özgün; Ozdes, Duygu; Ozeken, Sengul Tugba; Top, Yener

    Natural and H2SO4-modified plane (Platanus orientalis L.) sawdust were used for the adsorptive removal of cationic methylene blue (MB) and anionic indigo carmine (IC) dyes from aqueous media to suggest a new and cost-effective method for wastewater treatment applications. The influences of initial pH values, concentrations of MB and IC, period of contact, dosages of the natural and modified plane sawdust, and the presence of foreign ions on the adsorption of dyes were investigated in the experimental studies to describe the best conditions of the most efficient adsorption processes. Initial pH values were optimized to be between 6.0-8.0 for MB and 2.0 for IC. Experimentations of Boehm titration, FTIR analysis, pHpzc value, and moisture content determinations were utilized to characterize the natural and modified sawdust materials. Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were used to evaluate the sorption mechanism. Maximum adsorption capacities of natural plane sawdust (NPS) and H2SO4-modified plane sawdust (MPS) calculated from the Langmuir isotherm model were 55.56 and 38.46 mg g-1 in MB adsorption, and 55.82 and 55.55 mg g-1 in IC adsorption, respectively. Results showed that the natural and H2SO4-modified plane sawdust serve as low-cost and efficient materials in the adsorptive removal of MB and IC dyes for industrial wastewater treatment applications.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleAçık Erişim2023
    Adsorptive removal of Cr(VI) and Cu(II) ions from aqueous solutions by a natural moss

    Ozeken, Sengul Tugba; Ozdes, Duygu; Duran, Celal

    The aim of the present research is to develop a new, fast, and easily applicable adsorption method for the removal of hazardous Cr(VI) and Cu(II) ions from the polluted industrial wastewater by using Racomitrium ericoides (Brid.) Brid. (REB), a type of moss. Although there are studies in the literature in which different moss species were used for the removal of heavy metals (HMs), REB was used for the first time in this study. Adsorption experiments were carried out through a batch system. The impact of significant experimental parameters showed that the optimum values of initial pH were 2.0 for Cr(VI) retention and 5.0 for Cu(II), and 360 min was selected as the optimum contact time for both HMs. An artificial neural network (ANN) model was applied to create a predictive model for the uptake efficiency of HMs. Adsorption kinetics of Cr(VI) and Cu(II) ions followed the pseudo-second order model. The maximum adsorption capacities of REB identified through the Langmuir model were 41.2 mg g-1 for Cr(VI) and 22.7 mg g-1 for Cu(II) ions. The results of the study demonstrated that REB can be utilized as an abundant, low-cost, and effective adsorbent in removal of HMs from aqueous solutions.

  • MakaleAçık Erişim2023
    Enhancement of adsorptive removal efficiency of an anionic dye from aqueous solutions using carboxylic acid-modified mulberry leaves: Artificial neural network modeling, isotherm, and kinetics evaluation

    Duran, Celal; Ozeken, Sengul Tugba; Camoglu, Aslihan Yilmaz; Ozdes, Duygu

    Natural mulberry leaves and carboxylic acid-modified mulberry (Morus alba L.) leaves were used for the first time to scrutinize the effects of modification on the retention efficiency of an anionic dye (Remazol Brilliant Blue R (RBBR)) from aqueous solutions to suggest an economical and promising adsorbent for the treatment of dye-contaminated water. The characterization of the adsorbents was accomplished through common techniques including SEM, FTIR, and pHpzc determination. Several parameters studied in batch experiments pointed out that the initial pH of 2.0 and the contact time of 240 min were optimum conditions for all the developed RBBR uptake processes. An artificial neural network (ANN) model was applied to formulate a forecast model for the uptake efficiency of RBBR. The experimental data were assessed by different kinetic and isotherm models to explain the mechanism of the developed processes in more detail. Maximum monolayer adsorption capacities of natural mulberry leaves and acetic acid-, citric acid-, and oxalic acid-modified mulberry leaves were determined as 64.5, 95.2, 84.8, and 91.7 mg g1, respectively, by the Langmuir isotherm model. These results demonstrated that the modification with carboxylic acids significantly increases the anionic dye adsorption capacity of the mulberry leaves.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim