Profile URL: https://hdl.handle.net/20.500.13091/11791
Job Title:Prof. Dr.
Email Address:aozkan@ktun.edu.tr
Main Affiliation:02.12. Department of Mining Engineering
Status: Current Staff
ORCID:
0000-0002-5780-788X
0000-0002-5780-788XScopus ID:
7006607822
7006607822YÖK Akademik: FAC672678D2D0794
Google Scholar:
MZbIkCIAAAAJ
MZbIkCIAAAAJWeb of Science ID:
AAO-7236-2020
AAO-7236-2020Name Variants:
Ozkan, Alper
7 results
Scholarly Output Search Results
Now showing 1 - 7 of 7
Article Citation - WoS: 8Citation - Scopus: 8Use of Ultrasonic Treatment as a Pre-Phase in the Shear Flocculation Process(Elsevier, 2023-09-01) Özkan, Alper; Eşmeli, KirazThe use of ultrasonic energy has mostly been investigated for the flotation process in mineral processing, but its application to flocculation with collectors is extremely limited. Therefore, in this study, the effect of ultrasound in the shear flocculation technique, was intended to be revealed by using a celestite sample. The initial studies carried out for this purpose showed that in the absence of any reagent, the ultrasonication decreased the surface charge of the mineral, which caused the coagulation of the celestite suspension. In this scope, the short application of ultrasound at high power (i.e., 2 min batch regime and 150 W) provided a more positive effect. In the flocculation process carried out with collectors, the use of ultrasonic energy as a pre-phase for the suspension enhanced the aggregation of celestite particles. This result also fits well with the rise in the contact angle and the decrease in the zeta potential of the mineral due to the ultrasound. However, when the ultrasound was applied directly to the flocculation phase (ultrasound-induced flocculation only), the aggregation of celestite particles was affected adversely. Consequently, it can be said that in the shear flocculation process, the ultrasonic treatment should be used as a pre-phase for mineral suspensions. In this case, the flocculation of fine mineral particles in suspensions with surfactants can be improved by ultrasonic processing.Article Effect of Ultrasound on the Dispersion of Kaolinite and Sepiolite Suspensions With and Without Sodium Silicate(IROST, 2021) Eşmeli Kiraz; Özkan AlperIn this study, the effect of the ultrasound process on the dispersion of kaolinite and sepiolite suspensions in the absence and presence of sodium silicate was investigated. The effects of ultrasonic device-dependent parameters such as power, treatment time, and application method (batch and continuous) on the dispersion of kaolinite and sepiolite suspensions were determined. Results of the studies carried out without sodium silicate showed the suspension stability values of kaolinite and sepiolite minerals presented some differences. While the stability of the kaolinite suspension decreased at high power ultrasonic values, it increased slightly for the mineral sepiolite. Also, the stability of the kaolinite suspension decreased, while the stability of sepiolite increased with a prolonged ultrasonic treatment time. It was also found that the application of ultrasound did not affect the isoelectric point (iep) of these clay minerals. In the presence of sodium silicate as a dispersant, the dispersion of these mineral suspensions increased depending on ultrasonic power and treatment time. Moreover, higher suspension stability values were obtained with the ultrasound application. In addition, the negative zeta potential values of clays after ultrasonic treatment were higher than those without ultrasound. The findings obtained showed that kaolinite and sepiolite suspensions were more successfully dispersed by ultrasonic treatment.Doctoral Thesis Ultra Sesin Farklı Reaktifler Varlığında Mineral Süspansiyonlarının Kararlılığına Etkisinin Araştırılması(Konya Teknik Üniversitesi, 2019) Eşmeli, Kiraz; Özkan, AlperBu çalışmada, ilk olarak ultra ses işleminin mineral (selestit, kolemanit, galen, kuvars, kaolin ve sepiyolit) süspansiyonlarının kararlılığı üzerine etkisi araştırılmıştır. Bu bağlamda, ultrasonik cihazın güç değeri, ultra ses muamele süresi, ultrasonik probun dalma derinliği ve uygulama şekli (kesikli ve sürekli) değişimlerinin süspansiyon kararlılığı üzerine etkisi belirlenmiştir. İkinci olarak, mineral süspansiyonlarının farklı amaçlarla kullanılan reaktifler (toplayıcı, flokülant, koagülant ve dispersant) varlığında ultra ses işleminin etkisi çalışma parametrelerine bağlı olarak ayrıntılı şekilde belirlenmiştir. Reaktif kullanılmadan gerçekleştirilen çalışmalar sonucunda, minerallerin süspansiyon kararlılık değerlerinin ultrasonik muamele ile azaldığı görülmüştür. Ayrıca, ultra ses uygulamasının minerallerin i.e.p noktası üzerinde kayda değer bir etki oluşturmadığı tespit edilmiştir. Toplayıcılar, flokülantlar ve koagülantlar varlığında gerçekleştirilen çalışmaların sonucunda, ultra ses işleminin minerallerin süspansiyon kararlılıklarını ultra ses uygulanmayan deneylere oranla daha fazla azalttığı dolayısıyla daha başarılı flokülasyon sağladığı tespit edilmiştir. Buna ilaveten, toplayıcılar varlığında gerçekleştirilen çalışmalarda ultrasonik işlem ile daha yüksek temas açısı değerleri ölçülmüştür. Ayrıca, ultra ses muamelesi ile minerallerin zeta potansiyeli ölçümleri kullanılan reaktiflere bağlı olarak farklılık göstermiştir. Mineral süspansiyonlarının dispersant varlığında gerçekleştirilen çalışmalarında ise daha yüksek kararlılık değerleri elde edilmiştir. Yani, ultra ses muamelesi ile minerallerin daha başarılı dispersiyonu gerçekleştirilmiştir. Ayrıca, dispersant varlığında gerçekleştirilen çalışmalarda ultra ses muamelesi ile minerallerin zeta potansiyeli negatifliği daha fazla artış göstermiştir.Master Thesis İnorganik Tuzların Linyitin Flotasyonuna Etkisi(Konya Teknik Üniversitesi, 2019) Şalgalı, İrem; Özkan, AlperBu çalışmada, düşük kaliteli linyit kömürünün flotasyonu NaCl, MgCl2 ve CaCl2 inorganik tuzları varlığında flotasyon kimyasalları olarak gazyağı ve köpürtücü kullanılarak ve kullanılmadan araştırılmıştır. Ayrıca, zeta potansiyeli ve temas açısı ölçümleri yapılmıştır. Linyit örneği geniş bir pH aralığında negatif bir yüzey şarjı sergilemiştir ve isoelektrik noktaya (iep) sahip değildir. Linyitin negatif şarjının büyüklüğünün tuzların 10-2 M konsantrasyonunun üzerinde önemli ölçüde azaldığı ve flotasyon reaktifleri olmaksızın linyitin flotasyonunun da aynı değerden daha yüksek tuz konsantrasyonlarında zayıf derecede oluştuğu belirlenmiştir. Linyit yüzeyleri üzerinde ölçülen temas açıları ise artan tuz konsantrasyonu ile artmaktadır. Linyit örneği su sever karaktere sahip olup, bu nedenle yüzdürülmesi çok güçtür. Dolayısıyla, linyitin toplayıcı ve köpürtücü ile flotasyonu yüksek reaktif derişimlerinde bile istenilen ölçüde başarılamamıştır. Flotasyon kimyasalları yokluğunda, yüksek inorganik tuz derişimleri ise düşük flotasyon performansları sağlamıştır. Ancak, linyitin flotasyonu inorganik tuzların varlığında gazyağı ve MIBC ile başarılabilmiştir. % 25.02 kül içeren linyitin flotasyon deneyleri, % 19 kül içerikli bir konsantrenin % 51.2 yanabilir verimle 10-1 M MgCl2 ve 8 gr/dm3 gazyağı konsantrasyonunda elde edilebildiğini göstermiştir. Ayrıca, MgCl2 ve CaCl2 tuzlarının linyit flotasyonunda NaCl tuzundan daha etkili olduğu belirlenmiştir.Article Citation - WoS: 2Citation - Scopus: 2Enhancement of Shear Flocculation of a Galena Suspension by Ultrasonic Treatment(South African Institute of Mining and Metallurgy, 2023) Esmeli, K.; Ozkan, A.The enhancement of shear flocculation of a galena suspension by ultrasound in the presence of sodium isopropyl xanthate and potassium ethyl xanthate was investigated by studying the effects of surfactant concentration on flocculation efficiency, contact angle, and zeta potential. Strong flocculation was obtained under alkaline conditions (pH > 9) and a high ultrasound power level (150 W). Although the ultrasonic treatment increased the negativity of the zeta potential of the galena particles, this did not decrease the flocculation efficiency, thereby showing that the hydrophobic interactions between the particle were stronger than the electrical double-layer repulsion resulting from xanthate adsorption. The findings indicate that the ultrasonic treatment promoted the adsorption of surfactants onto the mineral surfaces. © 2023 South African Institute of Mining and Metallurgy. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 4Improvement of Colemanite Flocculation With Collectors by Ultrasound Treatment(TAYLOR & FRANCIS INC, 2021-06-16) Özkan, Alper; Eşmeli, KirazIn this study, the influence of ultrasound on the stability of colemanite suspension was first studied without reagents, and the effects of ultrasound power value, treatment regime (batch and continuous), probe immersion depth, and treatment time on the suspension stability were determined. Then, the effects of ultrasound on the flocculation of colemanite with sodium dodecyl sulfate, Aero 845, and sodium oleate were investigated, and changes occurred in the flocculation efficiency, zeta potential and contact angle values were shown depending on the collector concentration. The experimental findings revealed that the application of ultrasound reduced the suspension stability; that is, enhanced flocculation of colemanite particles occurred due to the ultrasonic promotion. By the ultrasonic treatment, the contact angles measured on the mineral surface in the presence of these collectors increased. In addition, the ultrasonic treatment led to increases in the surface charge of colemanite mineral with these surfactants. These results indicated that the ultrasound increased the adsorption of collectors on the mineral surfaces, as a result of this, the hydrophobization of the colemanite surfaces improved, and thus the flocculation of colemanite enhanced.Article Citation - WoS: 2Citation - Scopus: 2Lignite Flotation in Inorganic Salt Solutions(TAYLOR & FRANCIS INC, 2019) Özkan, Alper; İlkay, I. S.; Eşmeli, Kiraz; Ilikay, I. S.The flotation of low-quality lignite coal in the presence of NaCl, MgCl2 and CaCl2 inorganic salts with/without the use of kerosene and MIBC as flotation chemicals was investigated in this study. In addition, the zeta potential and contact angle measurements were performed. The lignite sample exhibited a negative surface charge over a broad pH range and had no isoelectric point (iep). It was determined that the magnitude of negative charge significantly decreased above 10(-2) M concentration of the salts and the flotation of lignite without flotation reagents also started to take place at concentrations higher than the same value. The contact angles measured on the lignite surfaces also increased with increasing salt concentration. The lignite sample was hydrophilic, and therefore very difficult to float. Consequently, the flotation of lignite with collector and frother was not achieved to the desired extent, even using high reagent concentrations. In the absence of flotation chemicals, high concentrations of these salts also provided low flotation performances. However, the flotation of lignite could be achieved with kerosene and MIBC in the presence of inorganic salts. In addition, it was determined that MgCl2 and CaCl2 salts were more effective on the lignite flotation than NaCl salt.
Research Topics
Domains
Physical Sciences
Fields
Environmental ScienceEngineeringChemistry
Subfields
Water Science and TechnologyMechanical EngineeringPhysical and Theoretical ChemistryBiomedical Engineering
Specific Research Areas
Minerals Flotation and Separation Techniques
Mineral Processing and Grinding
Electrostatics and Colloid Interactions
Coagulation and Flocculation Studies
Metal Extraction and Bioleaching
Sustainable Development Goals
SDG data is not available
Documents
43
Citations
751
h-index
16
Documents
38
Citations
644
Publication Collaboration
| Affiliation Name | Count |
|---|---|
| Selçuk University | 29 |
| Sivas Cumhuriyet Üniversitesi | 14 |
| Konya Technical University | 5 |
| Necmettin Erbakan University | 2 |
| Pennsylvania State University | 1 |
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Data obtained from OpenAlex
| Journal | Count |
|---|---|
| INTERNATIONAL JOURNAL OF COAL PREPARATION AND UTILIZATION | 1 |
| Journal of Particle Science and Technology | 1 |
| Journal of the Southern African Institute of Mining and Metallurgy | 1 |
| PARTICULATE SCIENCE AND TECHNOLOGY | 1 |
| Ultrasonics | 1 |
Current Page: 1 / 1
Scholarly Output
7
Articles
5
Views / Downloads
10/34
Supervised MSc Theses
1
Supervised PhD Theses
1
WoS Citation Count
17
Scopus Citation Count
16
Patents
0
Projects
0
WoS Citations per Publication
2.43
Scopus Citations per Publication
2.29
Open Access Source
3
Supervised Theses
2
Scopus Quartile Distribution
Competency Cloud
