Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Güler, Ömer(2)
- Uysal, Turan(2)
- Yayla, Nihal(2)
- Çimen, Okay(2)
- Aslan, Naim(1)
- Ateş, Erdem(1)
- Aydogdu, Burcu(1)
- Boyrazlı, Mustafa(1)
- Dönmez, Cahit(1)
- Erdemoglu, Murat(1)
- Erturk Gurkan, Selin(1)
- Erust, Ceren(1)
- Erüst, Ceren(1)
- Hacı Mehmet Aydoğdu(1)
- Koç, Mümin Mehmet(1)
- Koç, Sukru(1)
- Sari, Ali(1)
- Sis, Hikmet(1)
- Unal, Ilkay(1)
- Uysal, T.(1)
- İlyas İzgüden(1)
- Şimşek, Telem(1)
Yayınlar
- MakaleAçık Erişim2026Geological Formation Environments of Rare Earth Elements: Examples from Around the World and Turkiye
Çimen, Okay; Dönmez, Cahit
Rare earth elements (REEs) are critical raw materials used in strategic fields such as defense, energy, electronics, lasers, and sensor technologies, and particularly in the production of permanent magnets including NdFeB and SmCo types. Since the early 2000s, the global supply of rare earth elements has become dominated by China for mining, beneficiation, and separation processes, as non-Chinese producers have lost competitiveness due to high capital requirements and the costs imposed by environmental regulations. This review addresses the geological formation environments, deposit types, and global reserve-resource distributions of REEs within an integrated framework. REE mineralization occurs within primary geological sources such as carbonatites, alkaline magmatic systems, and iron oxide copper-gold (IOCG) deposits, as well as in secondary sources including ion-adsorption clays, placers, and lateritic formations. Primary sources are generally enriched in light REEs and are characterized by high-cost production processes, whereas heavy REEs are predominantly obtained from secondary sources. Globally, REE reserves are estimated to be approximately 90-120 Mt, while potential resources are on the order of similar to 480 Mt, with China occupying a leading position in terms of both reserves and resources. In Europe, Greenland, Sweden, Finland, Norway, Germany, and Turkiye are among the regions with significant REE potential. In Turkiye, the principal REE areas defined at the deposit scale are the Eski & scedil;ehir-K & imath;z & imath;lcaoren (Beylikova) and Malatya-Kuluncak districts. These districts are associated with alkaline magmatism and display enrichment particularly in Nd and Pr (beyond La and Ce), rendering them strategically important for NdFeB permanent magnet production. Recent studies conducted by Eti Maden indicate that the Eski & scedil;ehir-K & imath;z & imath;lcaoren area hosts a large-scale resource of approximately 694 Mt with total REE grades of1.5-1.8%. The Eski & scedil;ehir-K & imath;z & imath;lcaoren area is related to the extensional tectonic regime of Western Anatolia, whereas the Malatya-Kuluncak area is associated with post-collisional alkaline magmatism of Late Cretaceous-Early Paleocene age developed within the Central Anatolian Crystalline Complex. The presence of similar alkaline systems across Turkiye indicates significant potential for REE exploration and critical mineral strategies. This synthesis provides a comprehensive geological reference framework for the development of REE exploration strategies, the diversification of global supply chains, and evaluation of Turkiyes'REE potential.
- MakaleYalnız künye2026Scopus SJRQ2An integrated process for rare earth elements recovery and silica production from Turkish bauxite-related ores
Uysal, Turan; Erüst, Ceren; Erdemoglu, Murat; Sis, Hikmet
The evaluation of bauxite-associated shales as a secondary source of rare earth elements (REEs) is strategically important for securing a sustainable supply of critical raw materials used in advanced technologies. In this study, shale ore associated with bauxite, unsuitable for aluminium production due to its high silica content, was investigated as a potential resource for valuable REEs. The effect of thermal activation on REE recovery was examined, and the potential use of the leach residue as a silica source was assessed. Based on acid leaching results, the optimum calcination temperature was identified as 700 degrees C. Under these conditions, high REE recoveries were achieved: 92.9% La, 89.9% Ce, 89.0% Pr, 88.7% Nd, and 73.0% Sm. After leaching, the residue was enriched in alumina and silica. To improve silica purity and recover remaining REEs and Al, a second-stage leaching process was applied. This resulted in a byproduct containing 55% SiO2 with a specific surface area of 48 m2 g-1, indicating its potential as a silica source. The results demonstrate that bauxite-associated shale can be sustainably valorised through intensive milling, calcination, and acid leaching, enabling efficient REE recovery and the production of a silica-rich byproduct. L'& eacute;valuation de schistes associ & eacute;s & agrave; la bauxite comme source secondaire d'& eacute;l & eacute;ments de terres rares (ETR) est strat & eacute;giquement importante pour garantir un approvisionnement durable en mati & egrave;res premi & egrave;res critiques utilis & eacute;es dans les technologies avanc & eacute;es. Dans cette & eacute;tude, on a examin & eacute; le minerai de schiste associ & eacute; & agrave; la bauxite, inappropri & eacute; & agrave; la production d'aluminium en raison de sa teneur & eacute;lev & eacute;e en silice, comme ressource potentielle d'ETR pr & eacute;cieux. On a examin & eacute; l'influence de l'activation thermique sur la r & eacute;cup & eacute;ration des ETR et l'on a & eacute;valu & eacute; l'utilisation potentielle du r & eacute;sidu de lixiviation comme source de silice. D'apr & egrave;s les r & eacute;sultats de la lixiviation acide, on a identifi & eacute; la temp & eacute;rature optimale de calcination & agrave; 700 degrees C. Dans ces conditions, on a obtenu des r & eacute;cup & eacute;rations d'ETR & eacute;lev & eacute;es: 92.9% de La, 89.9% de Ce, 89.0% de Pr, 88.7% de Nd et 73.0% de Sm. Apr & egrave;s la lixiviation, le r & eacute;sidu & eacute;tait enrichi en alumine et en silice. Afin d'am & eacute;liorer la puret & eacute; de la silice et de r & eacute;cup & eacute;rer les ETR et l'Al restants, on a appliqu & eacute; une deuxi & egrave;me & eacute;tape de lixiviation. Cela a engendr & eacute; un sous-produit contenant 55% de SiO2 et pr & eacute;sentant une surface sp & eacute;cifique de 48 m2/g, indiquant son potentiel en tant que source de silice. Les r & eacute;sultats d & eacute;montrent que le schiste associ & eacute; & agrave; la bauxite peut & ecirc;tre valoris & eacute; de mani & egrave;re durable par broyage intensif, calcination et lixiviation acide, permettant une r & eacute;cup & eacute;ration efficace des ETR et la production d'un sous-produit riche en silice.
- MakaleYayıncıda açık erişim2026Scopus SJRQ1Geoeconomic dependency in selected rare-earth metals and compounds: A product-level trade network analysis
Ateş, Erdem
This study examines trade concentration, network structure, and China-centered import dependency in three selected rare-earth metal and compound categories (HS 280530, HS 284610, and HS 284690) over 2012–2024. Using bilateral trade data from the CEPII BACI database, the analysis combines concentration ratios and the Herfindahl–Hirschman Index with bilateral trade-flow networks, centrality measures, cosine-similarity networks, and country-level China Import Dependency Ratios (CID). The results reveal substantial product-level heterogeneity. Trade concentration and network structure evolve differently across the three categories, while changes in similarity-network density, community structure, and modularity are particularly pronounced for HS 284690. Trade shares and network centrality do not always move in parallel, indicating that market concentration and structural network position capture distinct dimensions of trade organization. Country-level dependency analysis further shows increasing reliance on China across all three product categories: both mean CID and the share of importing countries sourcing at least 50% of their imports from China increase between 2012 and 2024. Overall, the findings demonstrate the value of integrating concentration, network, and dependency measures to identify product-specific patterns of geoeconomic exposure in selected rare-earth metals and compounds.
- MakaleAçık Erişim2026Scopus SJRQ2Solvent extraction of rare earth elements and α-alumina production from pregnant leaching solution obtained from Turkish bauxite-related ore
Erust, Ceren; Uysal, Turan
The use of bauxite-related shales as a secondary source for the extraction of rare earth elements (REEs) is very important to meet the raw material supply, which is the keystone of advanced technology applications. This study presents the investigation into the recovery of REEs from Kızıldağ shale ore and the potential utilization of its leach residue as a silica source. Mineralogical analysis revealed that the ore predominantly consists of paragonite, muscovite, quartz, pyrophyllite, and calcite. Calcined ore was subjected to acid leaching, and the resulting pregnant solution was purified using solvent extraction to separate from aluminum the ∑REEs with a content of 1887.35 ppm. Optimal solvent extraction conditions 1.5 M D2EHPA, 50% O/A ratio, pH 1.5, and 15-minute mixing time achieved 95% total REE extraction, with efficiency in the order Pr > La > Nd > Ce > Dy > Y > Sc. To purify Al from the Fe- and K-rich solution post-SX, electrolysis was performed, resulting in 97.16% precipitation efficiency of Al as Al(OH)3 at pH 5. The precipitate was subsequently roasted at 1100°C to produce α-alumina with 75.2% Al2O3 content. These findings confirm the technical feasibility of recovering REEs and producing coarse-purity alumina from Kızıldağ shale ore.
AtıfScopus1WoS3OpenAlex1
İncele - MakaleAçık Erişim2025Scopus SJRQ2Effect of neodymium addition on the structural, mechanical, and magnetic properties of FeCoNiCu(MnCr)0.5 high entropy alloys
Yayla, Nihal; Şimşek, Telem; Boyrazlı, Mustafa; Güler, Ömer
Neodymium (Nd), a rare earth element, was incorporated into the [FeCoNiCu(MnCr)0.5] high-entropy alloy (HEA) at weight percentages of 0.5%, 1%, 2%, and 5%. The alloys were synthesized successfully using the arc melting method. X-ray diffraction (XRD) analysis confirmed that both the undoped and Nd-doped alloys exhibit a single-phase solid solution with a face-centered cubic (FCC) crystal structure, consistent with thermodynamic predictions derived from the Miedema model. Scanning electron microscopy (SEM) revealed a dendritic structure in the undoped alloy, which was replaced by Cu- and Cr-rich regions in the 5% Nd-doped alloy, as confirmed by energy dispersive spectroscopy (EDS). Differential scanning calorimetry (DSC) indicated an endothermic peak in the undoped alloy and minor thermal responses in Nd-doped samples, without distinct phase transitions within the 0–800 °C range. Mechanical testing demonstrated substantial enhancements in both hardness and tensile strength with increasing Nd content. The 5% Nd-doped alloy exhibited the highest performance, achieving a Vickers hardness of 370 HV and a tensile strength of 1186 MPa. Magnetic testing indicated ferromagnetic behavior in all samples, with Nd additions significantly enhancing magnetic properties. Notably, the 5% Nd-doped alloy achieved a saturation magnetization (Ms) of 41 emu/g and a coercivity (Hc) of 6.3 Oe, highlighting improved magnetic softness and rapid magnetization loss characteristic of soft magnetic materials.
AtıfScopus2WoS1OpenAlex1İncele - Derleme MakaleYalnız künye2025Scopus SJRQ1A short review of structural, mechanical and magnetic properties of high and medium entropy alloys added rare earth elements
Yayla, Nihal; Güler, Ömer
This study presents a comprehensive review of the structural, mechanical and magnetic properties of high and medium entropy alloys (HEA and MEA) with rare earth elements (REE) additions. The addition of REE has been shown to have significant effects on phase transformations, microstructural arrangements and thermodynamic stability. Studies in the literature show that REE addition improves properties such as hardness, strength, deformation resistance and magnetic performance. In particular, changes such as transitions from FCC to HCP, formation of intermetallic phases and grain refinement have been observed in phase types with the addition of elements such as Gd, Y and Nd. REE added HEAs offer great potential for modern engineering and advanced technology applications with their superior magnetic moments, magnetocaloric effects and thermal stability. However, there is limited information in the literature on REE added HEAs. This review aims to provide a comprehensive framework for the development of REE added HEAs and to serve as an important reference point for future research.
AtıfScopus7WoS7OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ1Assessment of toxicity and oxidative stress induced by rare earth oxide nanoparticles in brine shrimp (Artemia salina)
Unal, Ilkay; Erturk Gurkan, Selin; Aydogdu, Burcu
This study meticulously explored the oxidative stress effects induced by lanthanum (III) oxide (La2O3), erbium (III) oxide (Er2O3), and yttrium (III) oxide (Y2O3) nanoparticles on Artemia salina, with the objective of evaluating the environmental toxicity of rare earth oxide nanoparticles. The characterization of the nanoparticles was conducted using a suite of advanced techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential analysis. Artemia salina, a widely recognized model organism in ecotoxicological research, was exposed to these nanoparticles under meticulously controlled laboratory conditions. The investigation focused on quantifying oxidative stress markers, such as reduced glutathione (GSH), malondialdehyde (MDA), and antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST). The findings revealed significant alterations in these biomarkers, indicating nanoparticle-induced oxidative stress, which varied according to the type of nanoparticle and the duration of exposure.
AtıfScopus9OpenAlex9
İncele - Yüksek Lisans TeziAçık Erişim2023Sm2(CO3)3 ve Nd2(CO3)3 çözebilecek derin ötektik sıvıların geliştirilmesi ve bu karbonatların elektrokimyasal aktivasyona karşı tepkisinin araştırılması
Hacı Mehmet Aydoğdu
Bu tez çalışmasında, nadir toprak karbonatlarının liç işlemi için uygun derin ötektik çözücüler belirlenmiştir. Viskozite ve iletkenlik ölçümleri gibi fiziksel özellikler gerçekleştirilmiştir. Deneylerde kullanılacak olan DES'lerin elektrokimyasal davranışı hakkında bilgi elde etmek için Dönüşümlü Voltametri (CV) ve Kronoamperometri (CA) teknikleri uygulanmıştır. TGA analizi, nadir toprak elementleri karbonatı içinde yaklaşık %10 hidrat gösterdi. Çıplak DES'lerin kararlı potansiyel aralıkları ve karbonatların ayrışmaya başladığı potansiyeller, mikro elektrota uygulanan CV ve CA teknikleri ile belirlenmiştir. Platin elektrot üzerinde ayrışan Nd ve Sm karbonat hidrat tozunun kimyasal bileşimini belirlemek için SEM-EDS ve XRD analizleri yapıldı. Sonuç olarak, nadir toprak elementi karbonat hidratların nadir toprak elementi oksitlerine dönüştüğü gözlemlendi. Elektrokatalitik aktivasyonun etkisini doğrulamak için, karbonatların liç etkinliği ilk olarak çıplak DES solventlerinde 55±5 oC'de 24 saat boyunca potansiyel uygulanmadan gerçekleştirildi. Daha sonra aynı deneysel liç düzeneği 6 saat boyunca elektrokatalitik aktivasyon ile çalıştırıldı. ICP-MS, çözünmüş nadir toprak elementleri için kullanıldı. Uygulanan pals teknikleri ve elektrokatalitik aktivasyon ile liç verimliliği %100'den fazla arttırılmıştır.
- Yüksek Lisans TeziAçık Erişim2022Nadir toprak elementleriyle katkılandırılmış borat camların fiziksel ve radyasyon zırhlama özelliklerinin incelenmesi
İlyas İzgüden
Bu çalışmada Ülkemizde yer alan zengin bor madeni rezervinin daha verimli kullanılması amacıyla ana maddesi bor oksit olan ve içerisine yine ülkemizde ham madde olarak bulunan ve yeni keşifler ve incelemelere konu nadir toprak elementleri katkılanarak hazırlanan ve kurşun katkılı camlara alternatif olabilecek ve yüksek teknoloji ürünlerinde (Akıllı cihaz ekranları, uzay ve sağlık teknolojileri gibi) kullanılabilecek yeni nesil radyasyon kalkanlayıcı camlar üretmektir. Üretimi yapılan ürünlerin öncelikle XRD yöntemi ile faz tanımlaması yapılmış ve numunelerin amorf yapısına sahip cam olduğu belirlenmiştir. Üretilen numunelerin FTIR yöntemi ile kimyasal bağları ve moleküler yapıları araştırılarak düzgün bağlar oluşturan camlar olduğu belirlenmiştir. Elde edilen numunelerin UV-Vis Spektroskopisi yöntemi ile ışık geçirgenliği ve soğurma spektrumları belirlenerek normal cam karakteri gösterdiği belirlenmiştir. Camların camsı özelliklerinin iyi sonuçlar verdiği tespit edilmiş ve mekanik özelliklerden yoğunluk, sertlik, kırılma toklukları ve gevreklikleri incelenmiş ve sonuçları değerlendirilmiştir. Cam örneklerinin radyasyon zırhlama ölçümleri Atatürk Üniversitesi Fen Fakültesi Fizik Bölümü Prof. Dr. Wolf Weyrich Yüksek Enerji Spektroskopisi Laboratuvarı'nda bulunan deney düzeneği kullanılarak yapılmış ve cam örneklerinin kurşun katkılı camlara alternatif olabilecek seviyede radyasyon kalkanlama yaptığı belirlenmiştir. Bu çalışmanın amacı yapılan nadir toprak elementleri katkılı borat camlarda radyasyon zırhlamanın yanı sıra mekanik ve fiziksel özelliklerinin iyileştirilmesinde yardımcı olacak bir yayın (Tez) oluşturarak bilimsel çözümler sunmaktır.
- MakaleAçık Erişim2022Scopus SJRQ3Economic analysis of rare earth element processing methods for Mountain Pass ore
Uysal, T.
The increasing demand for rare earth elements (REE) in highly strategic sectors such as hybrid electric vehicles, renewable energy, communication technologies, and the defense industry has made REE production methods important. In recent years, studies on REE have increased rapidly; however there are many studies on REE, there are not enough studies in the literature on the economics of the beneficiation process. RE ores are generally leached after beneficiation by gravity, magnetic and flotation methods. In this study, direct leaching, attrition scrubbing and leaching, and flotation and leaching methods are evaluated economically based on the data for the Mountain Pass (MP) facility. According to the sensitivity analysis performed as a function of capital cost (CAPEX), operating cost (OPEX), and rare earths oxides (REO) recovery, REO recovery has the biggest effect on the process economies. Although the flotation method entails additional investment and operating costs, transportation and operating costs are significantly reduced result of the higher grade and recovery. The flotation method is more profitable, with larger NPV and IRR values and a shorter payback period.
AtıfScopus8WoS8OpenAlex10İncele - Kitap BölümüYalnız künye2022X-Ray Computed Tomography and Magnetic Resonance Imaging Applications of Magnetic Nanoalloys and Nanocomposites
Aslan, Naim; Koç, Mümin Mehmet
Metallic nanoparticles were used in different medical and biological applications. Such applications can cover targeted drug delivery, biomarking, MRI imaging, CT imaging, magnetic hyperthermia, etc. Metallic nanoparticles show outstanding properties with high electron affinity and good electrical, electronic, and optoelectronic properties with possible magnetic characteristics. In this regard, magnetic nanoparticles and magnetic nanoalloys are found to be a suitable candidate to be used in imaging applications. In this chapter, concepts of X-ray computed tomography imaging and magnetic resonance imaging are briefly discussed. Magnetic nanoparticles, nanoalloys, and nanocomposites used in imaging, diagnostics, and theranostic applications were illustrated.
AtıfScopus2OpenAlex1İncele - MakaleAçık Erişim2013Scopus SJRQ2RARE EARTH ELEMENT (REE) GEOCHEMISTRY AND GENESIS OF OIL SHALES AROUND DAGHACILAR VILLAGE, GOYNUK-BOLU, TURKEY
Çimen, Okay; Koç, Sukru; Sari, Ali
The study area is located in the south of Daghacilar village of Goynuk town in Bolu Province, Turkey. This study is a pioneering work in Turkey on the genesis and environmental characteristics of oil shales and other shallow marine-type sedimentary rocks regarding their major and rare earth element contents. The abundances of SiO2, Al2O3, TiO2, K2O and Fe2O3 decrease in the following order: claystone > oil shale > marl. CaO and MgO abundances are ranked in the decreasing order as follows: marl > oil shale > claystone. These results reveal the presence of two different genetic groups - detrital and marine. The same groups were also established in the correlation studies of elements. TOT/C and TOC contents of rocks observe the following order: oil shale > marl > claystone, and as a result of variations in redox conditions they also vary in a wide range. Total carbon and total organic carbon are positively correlated with the group representing clays and negatively correlated with CaO, MgO and MnO. That is why TOT/C and TOC are associated with clays. The positive correlations between some major oxides (e.g. SiO2, Al2O3, Fe2O3, TiO2 and K2O) and REE might indicate that clays and iron oxy-hydroxyls play an important role in transportation and deposition processes. The only slight negative Ce and positive Eu anomalies and Ce/Ce* and Eu/Eu* values recorded in the depositional environment indicate low oxygenated and anaerobic (reducing) conditions.
AtıfWoS6OpenAlex9İncele
