Profile URL: https://hdl.handle.net/20.500.13091/11698
Job Title:Prof. Dr.
Email Address:hkahraman@ktun.edu.tr
Main Affiliation:02.01. Department of Chemical Engineering
Status: Current Staff
ORCID:
0000-0002-6368-6463
0000-0002-6368-6463Scopus ID:
55370555800
55370555800YÖK Akademik: AB7CBD25254259B6
Google Scholar:
Gy_LhpgAAAAJ
Gy_LhpgAAAAJWeb of Science ID:
IFE-1098-2023
IFE-1098-2023Name Variants:
Tutar Kahraman, Havva Tutar, Havva
16 results
Scholarly Output Search Results
Now showing 1 - 10 of 16
Conference Object ' Synthesis' of Silver Nanoparticles and Evaluation of Their Catalytic Activity on Reduction of Methylene Blue(Sage Publication, 2019) Saygılı, Tansu; Kahraman Tutar, Havva; Avcı, Ahmet; Pehlivan, ErolSynthesis of metallic nanoparticles can be realized by various methods such as chemical vapour deposition, physical vapor deposition, microwave-assisted synthesis, sol-gel method, ultrasonication method, electrochemical synthesis and chemical reduction of metallic ions. However, these techniques are expensive, non-ecofriendly and often contain harmful chemicals. As a result of increasing interest in green chemistry and other biological processes, scientists have turned to an eco-friendly nanoparticle synthesis that is simple, affordable, compatible with biomedical and pharmacological applications. Different contents existing in plant extracts such as polysaccharides, polyphenols, aldehydes, ketones, proteins/enzymes, amino aids and caffeine can reduce metal ions and stabilize the nanoparticles to preferred sizes and shapes. A green approach for the synthesis of silver nanoparticles (AgNPs) using water extract of Tussilago farfara plant under ambient conditions is reported in this study. The formation of AgNPs was analyzed by UVvisible spectrophotometer. Further, the effects of pH, temperature, and time on the formation of AgNPs were studied. From the results, it can be claimed that the formation of AgNPs mainly depends on the pH of the reaction medium. The formation of AgNPs occurs in neutral and basic pH which is evident from visual observation. Moreover, the catalytic effectiveness of the synthesized green catalyst, AgNPs, was also investigated in catalytic reduction of Methylene Blue (MB) dye. The reduction of dyestuff is confirmed by the decrease in absorbance maximum values of MB with respect to time using UVvisible spectrophotometer. The reaction was completed within 10 min, inferring excellent catalytic properties of silver nanoparticles in the reduction of MB.Article Citation - WoS: 5Citation - Scopus: 6Production of Pla-Based Agnps-Containing Nanofibers by Electrospinning Method and Antibacterial Application(Springer Science and Business Media Deutschland GmbH, 2023-08-28) Saygılı, T.; Kahraman Tutar, Havva; Aydın, G.; Avcı, A.; Pehlivan, E.; Kahraman, Havva TutarNanobiotechnology has achieved great advances in the field of scientific research in past years. Nanoparticles (NPs) with diameters ranging from 1 to 100 nm are the focus of nanotechnology. Green synthesis of encapsulated silver nanoparticles (eAgNPs) was carried out by using Solidago virgaurea L. (SvL) and Tussilago farfara L. (TfL) extract as reducing/protecting agent. An UV–vis spectrophotometer was used to determine the optimal conditions to produce eAgNPs from plant extracts, including pH, temperature, plant extract, and mixing times. The optimal conditions for AgNPs synthesis from the SvL plant and TfL plant were (1:1) extract-AgNO3, 24 h mixing time, and a temperature of 25 °C. SEM, TEM, FTIR, and UV–Vis Spectrophotometer analyses were carried out to ascertain the surface characterization and structural properties of eAgNPs and the nanofibrous mats' physicochemical characteristics. The results of the analysis revealed that the eAgNPs are nanosized and contain silver. eAgNPs-doped nanofiber production from polylactide acid (PLA) polymer was realized by electrospin method. The required production parameters for the electrospinning method of producing PLA-based nanofibers were investigated. Nanofiber was produced by combining 0.5 and 1% AgNPs in an 8% PLA solution. The biological effects of the developed PLA@eAgNPs nanofibrous mats were examined in vitro. The antibacterial activity of nanofibers against E. coli was determined using the agar diffusion method. eAgNPs and PLA-based nanostructured materials are suggested as bioactive coatings capable of preventing the development of microbial population on surfaces relevant to healthcare. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Article Citation - WoS: 9Citation - Scopus: 10Novel Sandwiched Composite Electro-Spun Mats Based on Polyacrylonitrile and Polyvinyl Butyral for Fast Oil-Water Separation(SPRINGER, 2019-05-07) Kahraman, Havva; Avcı, Ahmet; Pehlivan, ErolIn recent years, the issue on oil pollution in water has drawn continuous attention of researchers. Wastewater containing oil is generated in various industrial technologies, such as petrochemical, leather, textile, food, steel, and metal-finishing industries. Thus, oil sorbents are very commonly used during oil spills cleanup operation for their cost-effectiveness and affordability. In the present work, a novel sandwiched composite electro-spun nanofibrous mat (SCEM) was generated by electro-spinning technique. This sandwiched composite electro-spun mat was fabricated by sandwiching the chitosan-incorporated polyvinyl butyral nanofiber mat between two layers of polyacrylonitrile electro-spun mats. Surface morphology of the generated multilayer nanofibrous mat was observed by the static water contact angle measurement, SEM and FTIR analyses. SCEM was modified by alcoholysis reaction to increase the hydrophobicity and oleophilicity properties by enhancing the surface roughness. After fabrication and modification processes, oil-absorption capacities of single mats, SCEM, and modified mat designated as M-SCEM were investigated and calculated in terms of weight gains. Mats with sandwich structure exhibited excellent absorption capacities up to 100-140 times their own weight for motor oil. The obtained results suggest that these characteristics make spun bond nanofibrous mat a promising oil sorbent material for efficient oily water remediation.Article Citation - WoS: 20Citation - Scopus: 20Evaluation of Anion-Exchange Resins on the Removal of Cr(vi) Polluted Water: Batch Ion-Exchange Modeling(SPRINGER HEIDELBERG, 2019-08-01) Kahraman, Havva; Pehlivan, ErolThis study was performed to evaluate Cr(VI) removal performance of three anion-exchange resins with different quaternary amine functional groups by varying the conditions of the solution phase. The effects of process variables on the sorption, such as solution pH, temperature, adsorbent dose, phases contact time, and initial Cr(VI), concentration were performed at laboratory condition. The suitability of Freundlich, Langmuir, and Scatchard isotherm models was investigated for Cr(VI)-resin equilibrium. According to the results, calculated maximum ion-exchange capacities were 280.25 mg/g, 147.67 mg/g, and 163.67 mg/g of Cr(VI)/g, for Eichrom 1-X4, Lewatit M+ M800, and Lewatit A8071, respectively. The sorption kinetics and thermodynamic parameters for the equilibrium were studied for all three resins.Article Modified Meerschaum for Removal of Methylene Blue Dye from Aqueous Solutions: Characterization, Adsorption Behavior, Performance Evaluation(International Information and Engineering Technology Association, 2025-09-30) Radha, M.A.; Ahmed, Z.M.A.; Kahraman, H.T.; Pehlivan, E.; Gubari, M.Q.This study investigates the removal of methylene blue (MB), a cationic dye, from aqueous solutions using modified nano-meerschaum (mod-nM/3APTS) functionalized with 3-aminopropyl triethoxysilane. Structural characterization by FTIR, EDX, and TEM confirmed the successful modification and improved surface activity. Batch adsorption experiments revealed that equilibrium was reached within 120 minutes, with adsorption efficiency strongly influenced by pH, adsorbent dosage, and initial MB concentration. The maximum adsorption capacity was 127.75 mg/g, consistent with the Langmuir isotherm model, indicating monolayer chemisorption. Kinetic studies showed that the adsorption process followed the pseudo-second-order model, while thermodynamic analysis confirmed that MB adsorption was spontaneous and endothermic. Furthermore, mod-nM/3APTS exhibited good regeneration performance, maintaining over 88% efficiency after five reuse cycles. These findings demonstrate that mod-nM/3APTS is a low-cost, reusable, and highly effective adsorbent for dye removal in wastewater treatment applications. ©2025 The authors.Article Citation - Scopus: 1Effective Oil/Water Separation Sorbent Based on Nylon 6,6-Organoclay Nanofiber Mats(Korean Fiber Society, 2024-11-21) Kahraman H.T.; Kılınç A.; Kurtuluş S.; Avcı A.; Pehlivan E.; Kurtuluş, Sibel; Avcı, Ahmet; Kılınç, Alev; Pehlivan, Erol; Kahraman, Havva TutarOil spills and marine pollution caused by oil spills have a serious effect on environment and human life. The efficient removal of oils, petroleum-based products, and organic solvents from water is important for protecting the environment. Oil-absorbent nanofiber mats with high oleophilicity were prepared by electrospinning in the present work. Nylon 6,6 is chosen as a crystalline polymer with oleophilic hydrocarbon chains that are linked by hydrophilic functional amides. There has been little research into using electrospun Nylon 6,6 as an oil absorbent to remove oil from water. Two different organically modified montmorillonites (o-MMT, with trade names Tixogel VP and Cloisite 20A—C20A) are separately incorporated into Nylon 6,6 polymer to produce nanofiber mats with more oleophilic properties. To achieve efficient dispersion and exfoliation of organoclays in Nylon 6,6/formic acid solution, ultrasonication is applied for 30 min, followed by mixing for 24 h with a magnetic stirrer. After reaching a more homogenous solution, Nylon 6,6-organoclay nanofiber mats were then successfully electrospun by the electrospinning technique and characterized by using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), and water contact angle measurement (WCA). The mechanical properties of the mats were also evaluated. The absorption behavior of the mats for motor oil and other domestic oils was investigated and the absorption capacity calculated in terms of weight gain. Differences in the absorption capacity of these three types of oil were found to be due to the surface tension of the solvents in the oil and viscosity. It has been found that the nanofibers produced have a very high oil absorption capacity in the case of a 2% loading of organoclay. These newly produced mats demonstrated excellent motor oil absorption of 60–80 times their own weight in motor oil. It can be concluded that these novel oil-absorbing materials are promising candidates for the treatment of wastewater containing oil. © The Author(s), under exclusive licence to the Korean Fiber Society 2024.Conference Object Decoration of Silver Nanoparticles Synthesized by Green Approach Onto Naturally Colored Nylon 6,6 Nanofibers: Investigation of Antibacterial Activity(Sage Publication, 2019) Kahraman Tutar, Havva; Yüksel, Emre; Altun, Kezban Buse; Aydın, GülsümSince, organic dyes are non-eco friendly and expensive, recent researches have been focused on natural dyes. Natural dyes can be derived from natural sources. Most are of plant origin and extracted from roots, wood, berries, lichens, leaves, flowers, nuts, and seeds. Generally, they show various colors and contain several pigments which can be easily extracted and used as a coloring agent. However, studies regarding the dyeing process with natural dyes are very limited due to easy availability of cheap synthetic dyes. Hence, this research aimed to produce colored nanofibers using plant extracts. Metallic nanoparticles with physicochemical properties different from bulk materials are widely applied in various fields such as environmental remediation, photocatalysis, imaging, catalysis, biosensors and biomedical applications. Nanoparticles have emerged due to unique physical and chemical properties, high surface to volume ratio as novel antimicrobial agents. Among them, silver nanoparticles (AgNPs) show excellent antimicrobial efficiency against organisms such as bacteria, fungi and viruse. As a result of increasing interest in green chemistry, an eco-friendly nanoparticle synthesis that is simple, affordable, compatible with biomedical and pharmacological applications have been widely preferred. In this regard, the aim of the present work was to decorate the AgNPs synthesized by green method onto colored Nylon 6,6 nanofibers. Firstly, Nylon 6,6 nanofibers were fabricated by electrospinning method followed by dyeing process using reddish orange and onion peel extracts. During dyeing process of the nanofibers, vinegar was used as a dye fixative agent. Secondly, synthesis of AgNPs using water extract of Alchemilla vulgaris plant under ambient conditions was performed. The formation of AgNPs was analyzed by UV–visible spectrophotometer. Synthesized AgNPs were decorated onto nanofibers by ultrasonication technique followed by mechanical mixing. The nanofibers were characterized using Scanning Electron Microscope (SEM) and Fourier-transform infrared (FT-IR) spectrophometer. The antibacterial acitivities of obtained novel nanofibers were investigated using Gram‐positive bacteria (Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli). The activity test shows that nanofibers showed better antibacterial activities against to Gram‐positive bacteria (Staphylococcus aureus) as compared to Gram‐negative bacteria (Escherichia coli).Article Citation - WoS: 3Citation - Scopus: 3Removal of Hexavalent Chromium (cr6+) From Aqueous Solutions by Chitosan-Halloysite Nanotubes Composite Hydrogel Beads(Bentham Science Publishers, 2025-02-01) Edebali, S.; Kahraman, H.T.; Karakaya, M.Ç.Background: In recent years, low-cost biomaterials have been used for sustainable applications to reduce the impact of wastewater treatment. The preparation of bio-based materials with a strong affinity for chromate plays a crucial role in the adsorption process. Methods: In this study, chitosan-halloysite nanotubes composite hydrogel beads (Ch-HNTs) were prepared for the removal of hexavalent chromium (Cr6+) from aqueous solutions. Ch-HNTs hydrogel beads were generated by incorporating HNTs into chitosan using a glutaraldehyde solution to achieve efficient crosslinking. The structure of the Ch-HNTs was characterized by SEM and FTIR analysis. These novel adsorbents were then tested for the adsorption of Cr6+ in serial batch experiments. For this purpose, the effect of pH, contact time, temperature, concentration of adsorbate, and adsorbent concentration on the extent of adsorption were investigated. Results: The adsorption rate for Cr6+ was maximum at an initial pH of 2 in 60 minutes of contact time. The experimental data were fitted to Langmuir adsorption isotherm. The adsorption data were fitted to the Langmuir adsorption isotherm. The maximum adsorption capacity of 72.22 mg Cr6+/g for Ch-HNTs was obtained according to the Langmuir adsorption isotherm. Conclusion: It is proposed that Ch-HNTs can be potential adsorbents for Cr6+ removal from dilute solutions. Nonetheless, further studies on adsorbing and removing various heavy metals using these novel beads in column systems can be planned. © 2025 Bentham Science Publishers.Article Amonyum Floroborat Katkılı Pan Nanofiberlerin Termal Davranışının İncelenmesi(2023-10-11) Kahraman, Havva Tutar; Ceyhan, Ayhan AbdullahBu çalışmada, Amonyum Floroboratın (AFB), Poliakrilonitril (PAN) polimerinin termal özelliklerine olan etkisi incelenmiştir. Bu amaç için, sürekli nanofiber üretim yöntemlerinden biri olan elektro-spin yöntemiyle, PAN ve AFB katkılanmış PAN (PAN-AFB) nanofiber formunda üretilmiştir. Üretilen nanofiberlerin ısıl bozunma davranışı termal gravimetrik analiz (TGA) ile incelenmiştir. Fiberlerin yapısal karakterizasyonu FT-IR ve SEM teknikleri kullanılarak gerçekleştirilmiştir. Elde edilen sonuçlara göre, PAN içerisine eklenen AFB miktarının artması ile nanofiberlerin ağırlık kaybının azaldığı ve termal kararlılığının arttığı gözlenmiştir. Polimer matrisine AFB katkı oranları %0,2, %0,4 ve %0,6 olarak uygulanmıştır. Bunun yanısıra, SEM analiz görüntüleri, AFB partiküllerinin Poliakrilonitril içerisinde homojen olarak dağıldığını göstermektedir. Deneysel çalışmaların sonuçlarına göre, AFB’nin PAN üzerindeki olumlu etkileri gözlenmiş ve termal direncini artırdığı sonucuna varılmıştır.Article Citation - WoS: 13Citation - Scopus: 17Synthesis of Silver Nanoparticles Using Alchemilla Vulgaris and Helichrysum Arenarium for Methylene Blue and 4-Nitrophenol Degradation and Antibacterial Applications(Springer Heidelberg, 2024-01-20) Tutar Kahraman, Havva; Kahraman, Havva TutarThis study aimed to evaluate the concept of green synthesis of metallic nanoparticles (silver nanoparticles, AgNPs) by plant extracts without using any toxic or hazardous materials. Alchemilla vulgaris (AV) and Helichrysum arenarium (HA) are used as capping and reducing agents to synthesize AgNPs (as coded AV-AgNPs and HA-AgNPs). Both synthesized AgNPs were characterized by UV-visible spectrophotometry, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and transmission electron microscope (TEM). The results of characterization exhibited that AgNPs were successfully synthesized. They are highly well-dispersed, mostly spherical shape with an average size 15-20 nm. Catalytic reduction of methylene blue (MB) and 4-nitrophenol (4-NP) was assessed using synthesized AgNPs as nano-catalysts in the presence of NaBH4. The catalytic activity of the synthesized AgNPs revealed significant results in terms of degradation of MB and 4-NP to 4-AP (4-aminophenol). The reduction reactions of MB and 4-NP happen within 6-7 min using synthesized AV-AgNPs and HA-AgNPs in the presence of NaBH4. According to the reusability analysis, synthesized AgNPs demonstrated excellent degradation performances by the more than 94% removal efficiency maintained after five reuse cycles. In addition, antibacterial activities of AgNPs were investigated against Escherichia coli (E. coli; Gram-negative bacteria) and Staphylococcus aureus (S. aureus; Gram-positive bacteria) by using quantitative well-diffusion method and the inhibition zones were determined using Mueller-Hinton agar (MHA) media. AV-AgNPs and HA-AgNPs showed strong antibacterial activities against E. coli with in inhibition zone diameters 25.5 and 25 mm, respectively. AV-AgNPs and HA-AgNPs were also extremely effective on S. aureus with high inhibition zone values of 22 and 24 mm, respectively. Finally, the fabricated silver nanoparticles could be excellent candidates for the separation of hazardous materials.
Research Topics
Domains
Physical Sciences
Fields
Environmental ScienceMaterials ScienceChemistryEngineering
Subfields
Water Science and TechnologyBiomaterialsOrganic ChemistryMaterials ChemistryMechanical Engineering
Specific Research Areas
Adsorption and biosorption for pollutant removal
Electrospun Nanofibers in Biomedical Applications
Nanomaterials for catalytic reactions
Nanoparticles: synthesis and applications
Extraction and Separation Processes
Sustainable Development Goals
6CLEAN WATER AND SANITATION
7
Research Products
11SUSTAINABLE CITIES AND COMMUNITIES
4
Research Products
14LIFE BELOW WATER
2
Research Products
7AFFORDABLE AND CLEAN ENERGY
1
Research Products
15LIFE ON LAND
1
Research Products
3GOOD HEALTH AND WELL-BEING
1
Research Products
Documents
15
Citations
268
h-index
9
Documents
12
Citations
222
Publication Collaboration
| Affiliation Name | Count |
|---|---|
| Selçuk University | 10 |
| Konya Technical University | 8 |
| Stevens Institute of Technology | 2 |
| KTO Karatay University | 2 |
| Sivas Cumhuriyet Üniversitesi | 1 |
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Data obtained from OpenAlex
| Journal | Count |
|---|---|
| ARABIAN JOURNAL OF GEOSCIENCES | 1 |
| Biomass Conversion And Biorefinery | 1 |
| BOR DERGİSİ | 1 |
| Current Analytical Chemistry | 1 |
| Environmental Science and Pollution Research | 1 |
Current Page: 1 / 2
Scholarly Output
16
Articles
9
Views / Downloads
49/89
Supervised MSc Theses
1
Supervised PhD Theses
0
WoS Citation Count
50
Scopus Citation Count
61
Patents
0
Projects
0
WoS Citations per Publication
3.13
Scopus Citations per Publication
3.81
Open Access Source
9
Supervised Theses
1
Scopus Quartile Distribution
Competency Cloud
