Profile URL: https://hdl.handle.net/20.500.13091/11537
Job Title:Prof. Dr.
Email Address:tagacayak@ktun.edu.tr
Main Affiliation:02.12. Department of Mining Engineering
Status: Current Staff
ORCID:
0000-0001-8120-8804
0000-0001-8120-8804Scopus ID:
23472006500
23472006500YÖK Akademik: 1C22FA7C0C19AB38
Google Scholar:
WKcIYF4AAAAJ
WKcIYF4AAAAJWeb of Science ID:
ABG-6977-2022
ABG-6977-2022Name Variants:
Agacayak, Tevfik Agacayak, T.
39 results
Scholarly Output Search Results
Now showing 1 - 10 of 39
Other The Effect Of Aerophine 3418a Collector Dosage On Niğde (ulukışla-madenköy) Complex Pb-zn Sulphide Ore Flotation(2021) Ağaçayak, Tevfik; Yılmaz, Nur BenanIn this study, grinding + flotation experiments were performed on the sample of complex Pb-Zn sulphide ore taken from Niğde (Ulukışla-Madenköy) region in Turkey. According to the mineralogical analysis of the ore sample used in experimental studies, it was determined that the ore composition contains calcite, quartz, pyrite, chalcopyrite, hematite, goethite, limonite, gypsum, galena, sphalerite, jarosite, arsenopyrite and marcasite minerals. In addition, Au and Ag grains were found to be inclusions in hematite, goethite and jarosite minerals. The experiments were carried out at a solid ratio of 30%, a flow rate of 10 L/min, a stirring rate of 1250 rpm and pH = 9. In flotation tests, lime is used as the pH regulator, zinc sulphate, sodium silicate as the depressant, sodium isobutyl dithiophosphine as the collector and methyl isobutyl carbinol as the frother. In the flotation studies, the effect of Aerophine 3418A collector dosage on flotation was investigated. As a result, a lead concentrate of 55.13% Pb was obtained and it was found that this concentrate contained 2489 ppm of Ag. The amount of Aerophine 3418A collector was determined as 10 g/t.Article Taguchi Metodu Kullanılarak Sülfürik Asit Ortamında Lateritik Cevherden Nikel Çözünmesinin İncelenmesi(2018) Ağaçayak, Tevfik; Aras, AliBu çalışmada, lateritik cevherden sülfürik asitli ortamda nikelin farklı koşullarda çözündürülmesi araştırılmıştır. Deney parametreleri olarak; süre, karıştırma hızı, sıcaklık, sülfürik asit derişimi ve tane boyutu seçilmiştir. Ortogonal dizi (OD) deneysel tasarım planı L16 olarak belirlenmiştir. Bu deneysel tasarım ile farklı şartlarda 16 adet liç deneyi gerçekleştirilmiştir. Sonuçlardan elde edilen metal çözünme verimleri (MÇV) göz önüne alınarak, her test koşulunun sinyal/gürültü (S/G) oranları hesaplanarak anlamlılık analizleri (ANOM) ve optimizasyon çalışmaları gerçekleştirilmiştir. Optimizasyon çalışmaları sonucunda en yüksek MÇV’nin ve S/G oranının Test 10’da elde edildiği görülmüş ve doğrulama deneyi ile karşılaştırılmıştır. Optimizasyon şartlarında yapılan liç testleri sonucunda (S/G) oranının 38,97 ve metal çözünme veriminin (MÇV) ortalama %88,97 olduğu belirlenmiştir. Ayrıca, deney sonuçlarına varyans analizi (ANOVA) uygulanmış ve her faktörün nikel çözündürülmesine olan katkısı belirlenmiştir.Master Thesis Rudna (lubin, Polonya) Bakır Cevherinin Flotasyon ile Zenginleştirme Olanaklarının Araştırılması(Konya Teknik Üniversitesi, 2024) Conde, Mamady; Ağaçayak, TevfikBu tez çalışmasında, Polonya'nın Lubin kasabasındaki KGHM Polska Miedz S.A şirketinden temin edilen cevher numuneleri kullanılmıştır. Numuneler, kumtaşı, şeyl ve dolomit olmak üzere üç farklı litolojik süreçte oluşmuştur. Cevherler sülfürlü bakır mineralleri (kalkosit, bornit, kalkopirit ve kovellit) içermektedir. -200 μm tane boyutuna indirilen numuneler, atomik absorpsiyon spektrometresi ile analiz edilerek %1,2 Cu içerdikleri tespit edilmiştir. Denver tipi flotasyon hücresinde yapılan dört deneyde, farklı tane boyutları (-200+125 ve -125+100 µm) kullanılmıştır. En iyi sonuçlar, 1a ve 1b flotasyon deneylerinde elde edilmiştir. Toplayıcı miktarının artması flotasyonu olumsuz etkilemiş ve en uygun toplayıcı miktarının 100 g/Mg olduğu belirlenmiştir. Henry eğrisi yöntemi ile yapılan analizlerde, farklı Alfa değerleriyle (1.39, 1.29, 1.24, 1.27) tatmin edici bakır geri kazanımları sağlanabileceği gösterilmiştir. Flotasyon işlemlerinde farklı şartlar ve reaktiflerin etkisinin incelenmesi önerilmektedir.Master Thesis Gümüşköy Kompleks Cevherinden Gümüşün Basınçlı Ortamda Çözündürme Şartlarının Belirlenmesi(Konya Teknik Üniversitesi, 2019) Apaydın, Burak; Ağaçayak, TevfikGünümüzde altın ve gümüş gibi değerli metalleri içeren cevherlerden altın veya gümüşün kazanılmasında tercih edilen ve uygulanan en yaygın yöntemlerden birisi siyanür liçi olarak bilinmektedir. Hidrometalurjik bir proses olan siyanürleme, 100 yıllardan beri altın ve gümüşü cevherlerden ve konsantrelerden ayırmak için kullanılmaktadır. Bu prosesin kullanılma sebebi ise düşük tenörlü ve çok ince tane boyut içeren cevherlerde yüksek verim oranlarında çalışılmasıdır. Gümüşün çözündürülmesi genellikle metal siyanür komplekslerinin karışımlarını içeren alkali siyanür çözeltileri kullanılarak gerçekleştirilmektedir. Bu çalışma, Gümüşköy (Kütahya) kompleks gümüş cevherinin kimyasal yöntemlerle zenginleştirilmesini kapsamaktadır. Bu amaçla, yüksek sıcaklık ve basınç kullanılarak siyanür liçi çalışmaları gerçekleştirilmiştir. Liç parametreleri olarak, tane boyutu, NaCN konsantrasyonu, sıcaklık, basınç, oksijen miktarı ve pH seçilmiş ve deneylerde tenör ve karıştırma hızı sabit tutularak bu parametrelerin kompleks gümüş cevherinden gümüşün çözündürülmesine etkisi incelenmiştir. Optimum sonuçların elde edildiği parametrelerin ise, tane boyutunu 10µm, NaCN konsantrasyonunu 1.2 g/lt, liç sıcaklığı 130°C, basıncı 10 bar, oksijen basıncı 1.5 bar ve pH ise 11 olduğu belirlenmiştir. Sonuç olarak, kompleks gümüş cevherinden gümüşün yüksek sıcaklık ve basınç kullanılarak siyanürlü ortamda çözeltiye alınabileceği görülmüştür.Article Citation - WoS: 3Citation - Scopus: 4Investigation of Co-Combustion Characteristics of Olive Bagasse, Coal and Their Respective Blends by Thermogravimetric Analysis (tga)(Taylor & Francis Inc, 2022-04-05) Ağaçayak, TevfikCo-combustion characteristic was investigated in detail to investigate the combustion of coal/olive bagasse and their different ratios blends (10%, 25%, 50%, and 75%) using the thermogravimetric analysis (TG) and the differential thermogravimetric analysis (DTG). Ignition and peak temperatures and other combustion characteristics for the samples were determined and correlated with the results obtained depending on the percentages of blends. As a results of the evaluation of all these parameters, it was thought that 25% olive bagasse and 75% coal blend were the most suitable value. In the final part of the work, the kinetic analysis of the samples was carried out by the Coats-Redfern method and the activation energies were determined. The activation energies of the coal/olive bagasse and their blends were assessed and compared. The calculated activation energy values for the combustion reactions of the samples ranged were found to be between 11.44 kJ/mol and 21.67 kJ/mol. As the blend percentage increased the olive bagasse showed a decreasing trend according to the ignition and peak temperature of the coal. It was determined that coal had more difficult combustible behavior than olive bagasse. In addition, a decrease in calorific values and an increase in comprehensive combustion index (CCI) value were observed as the percentage of olive bagasse blend increased.Article Citation - WoS: 1Citation - Scopus: 1The Potential of Sudanese Refractory Gold Ores Characterization and Pre-Treatment in Ariab Mines (vms) in Red Sea (sudan)(BERG FAC TECHNICAL UNIV KOSICE, 2023-09-19) Motasim, Mahmoud; Ağaçayak, Tevfik; Fathalrhman, Mohammed; Elhadi, Eltahir; El-GAK, Amin; Awdekarim, Abdelshakour; Seifelnasr, Ahmed Abdullah SadeekThis laboratory work demonstrates the ability to characterize and pretreat Sudanese refractory gold ores at Ariab mines to extract the gold with optimal parameters. Characterization studies were performed by AAS, XRF and XRD analysis to assess the abundance of elements and mineral phases. In addition, the acidity of the ore was examined to estimate the effective amount of lime. The ore was subjected directly to cyanidation without any pre-treatment. High oxidation reagent processes were carried out to pre-treat the ore. Chemical analysis results show the gold grade to be 1.37 g/t. In addition, the ore contained 51.78% Fe2O3, 43.40% SO3, 2.39% CuO, 1.47% SiO2, 0.35% Cr2O3, 0.17% CaO, 0.08% As2O3, 0.06% ZnO and 0.06% MnO. The XRD result shows that the ore phases are Pyrite (FeS2), Chatkaite (Cu6Fe+2Sn2S2) and Quartz (SiO2). The investigations of direct cyanidation elucidated that the ore can consume a high amount of cyanide with unsatisfactory recoveries for gold (Exgold & LE;39.41%). The influence of the cyanide concentration, pulp density (% by weight), leaching time hr, agitator speed and pH were examined in direct cyanidation experiments. In pre-treatment experiments, the effect of hydrogen peroxide (H2O2) and concentrations on gold recovery was studied. The pre-treatment of the ore with H2O2 achieved a good impact on the gold extraction performance. The higher gold extraction was obtained at hydrogen peroxide (H2O2) 300 ppm, cyanide concentration 3500 ppm, leaching time 10 hr, pH=10.5 and pulp density 40%.Article Citation - WoS: 14Citation - Scopus: 14Effect of Organic and Inorganic Compounds on Dissolution Kinetics of Chalcopyrite in Hydrogen Peroxide- Hydrochloric Acid System(Elsevier, 2022-05-01) Agacayak, Tevfik; Abdelraheem, Mohamed Taha OsmanThe addition of 2-Propanol as an organic substance and NaCl as an inorganic com-pound in hydrochloric acid with hydrogen peroxide as a strong leaching agent of chalcopyrite was investigated. The effects of the leaching parameters on copper extraction, such as stirring speed, H2O2 concentration, temperature, HCl concentration and solid/liquid ratio were studied. The max-imum final copper extraction of 54.55% was obtained with 600 rpm stirring speed, 1.5 M H2O2, 0.5 M HCl, 600 rpm, 50 C, 240 min of the reaction and particle size of -106 +75 mm. Further experiments were performed when the solid-to-liquid ratio (S/L), stirring speed, temperature, HCl,H2O2 and leaching time were kept constant to examine the influence of NaCl and 2-Propanol concentrations in the range of 0-0.5 M and 0-3 M, respectively. The results showed that the copper extraction was increased up to 58.11% with addition of NaCl. While copper extraction yield reached 94.25% in case of addition of 2-propanol with the optimum parameters(0.5 M HCl,50 C, 1.5 M H2O2, 600 rpm, particle size -106 +75 lm, solid liquid ratio 2g/L, 3 M 2-propanol). The chalcopyrite leaching in hydrogen peroxide- hydrochloric acid system was found to be described by the interface transfer and diffusion across the product layer with activation energy of 77.14 kJ/mol. Addition of 2-propanol suggested that the reaction was under product layer diffusion control and decreased the activation energy of chalcopyrite leaching to 67.98 kJ/mol. Crown Copyright (c) 2022 Published by Elsevier B.V. on behalf of King Saud University.Article Optimization and Modeling of Leaching Parameters Affectingnickel Dissolution From Lateritic Ore in Eskisehir (mihaliccikyunusemre) Using Box-Behnken Experimental Design(2020) Ağaçayak, Tevfik; Osman Abdelraheem Ahmed Mohamed TahaIn this study, optimization and modeling of leaching parameters affecting nickel dissolution from lateritic ore in Eskişehir (Mihalıççık-Yunusemre) were investigated using Box-Behnken design. Stirring speed (100-400 rpm, temperature (40-80°C), acid concentration (0.1-2 M) and dissolution time (30-180 min) were selected as experimental design parameters. 27 experiments were carried out by Box-Behnken experimental design in Minitab 16.0 program. After leaching experiments, the highest Ni dissolution percentages were obtained as 87.85%. The effective parameters and their interactions in nickel dissolution are described with a mathematical model. The results obtained from the experiments were subjected to ANOVA and multiple regression analysis. The R2 value of the model for nickel dissolution was calculated as 0.980. This showed that the predicted values are in good agreement with the observed values. In addition, three-dimensional response surface and contour graphs of the parameters affecting nickel dissolution efficiency were created and the results were examined.Article Citation - WoS: 1Citation - Scopus: 1The Investigation of Metallic Silver Dissolution Kinetics Using DL-Malic Acid With Hydrogen Peroxide Solution as an Eco-Friendly Leaching System: The Rotating Disc Method(Springer, 2025-07-23) Motasim, Mahmoud; Boyrazli, Mustafa; Aydogan, Salih; Agacayak, Tevfik; Ali, BabikerAlthough cyanidation remains widely employed for silver recovery due to its cost-effectiveness, it presents serious environmental and health hazards. In this study, the dissolution kinetics of silver were investigated in an environmentally benign leaching system composed of DL-malic acid and hydrogen peroxide, employing the rotating disc method. High-purity silver discs (99.99 pct) were used to examine the effects of rotation speed, disc surface area, temperature, and the concentrations of DL-malic acid and hydrogen peroxide on the leaching rate. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) were conducted to characterize the silver surface before and after leaching. Additionally, contact angle measurements were performed to evaluate the interfacial interaction between the leaching solution and the silver surface. The results demonstrated that the dissolution rate increased with temperature, rotation speed, hydrogen peroxide concentration, and surface area. However, elevated concentrations of DL-malic acid resulted in the formation of a passivating layer on the silver surface, likely due to chelation effects, which significantly impeded the access of protons (H+) to the silver surface, thereby reducing the dissolution rate. Contact angle analysis further indicated reduced wettability at higher DL-malic acid concentrations, with values reaching up to 87.80 deg. XRD analysis confirmed the partial oxidation of the silver surface, forming Ag2O. The reaction was determined to be chemically controlled, with an activation energy of 44.14 kJ/mol.Article Cleaning of Beysehir (bayavsar) Coal in Turkey With Hydrophobic Flocculation Using Waste Motor Oil(Univ Alexandru Ioan Cuza Iasi, Editura Univ, 2021) Ağaçayak, Tevfik; Ağca, OsmanIn this study, the hydrophobic flocculation behavior of lignite coal obtained from Beysehir region in Turkey and the effect of some parameters were investigated. These parameters were selected as pH, amount of dispersant, amount of binding liquid, flock growth time, stirring speed, flocculation time and solid ratio. The ash content (ash, %) and combustible recovery (CR, %) of the flocks obtained as a result of the experiments were determined. As a result of the studies, the optimum pH value (3), amount of sodium silicate (1 mL), amount of waste motor oil (3 mL), flock growth time (1 min), stirring speed (1250 rpm), flocculation time (2 min) and solid ratio (5 g) were determined. The hydrophobicity of fine coal grains was increased by using waste motor oil. According to the hydrophobic flocculation results of coal grains, flocks with 17.03% ash content and 99.06% combustion recovery were obtained. While the contact angle of the original coal was 44 degrees, it was observed that the contact angle of the obtained flocks reached 117 degrees. It was determined from experiments that the surfaces of the coal grains have a very high hydrophobicity. As a result, clean coal with a reduced ash content of 53.22% was obtained.
Research Topics
Domains
Physical Sciences
Fields
EngineeringEnvironmental Science
Subfields
Biomedical EngineeringMechanical EngineeringWater Science and TechnologyIndustrial and Manufacturing Engineering
Specific Research Areas
Metal Extraction and Bioleaching
Extraction and Separation Processes
Minerals Flotation and Separation Techniques
Mineral Processing and Grinding
Recycling and Waste Management Techniques
Sustainable Development Goals
11SUSTAINABLE CITIES AND COMMUNITIES
1
Research Products
12RESPONSIBLE CONSUMPTION AND PRODUCTION
1
Research Products
6CLEAN WATER AND SANITATION
1
Research Products
Documents
32
Citations
168
h-index
6
Documents
36
Citations
169
Publication Collaboration
| Affiliation Name | Count |
|---|---|
| Konya Technical University | 27 |
| Omdurman Islamic University | 13 |
| Selçuk University | 7 |
| Necmettin Erbakan University | 3 |
| Suez Canal University | 2 |
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Data obtained from OpenAlex
| Journal | Count |
|---|---|
| International Journal of Coal Preparation and Utilization | 3 |
| Acta Chemica Iasi | 2 |
| Hydrometallurgy | 2 |
| Acta Montanistica Slovaca | 2 |
| Canadian Metallurgical Quarterly | 2 |
Current Page: 1 / 5
Scholarly Output
39
Articles
31
Views / Downloads
118/333
Supervised MSc Theses
5
Supervised PhD Theses
1
WoS Citation Count
71
Scopus Citation Count
67
Patents
0
Projects
0
WoS Citations per Publication
1.82
Scopus Citations per Publication
1.72
Open Access Source
20
Supervised Theses
6
Scopus Quartile Distribution
Competency Cloud
