Th ve bazı nadir toprak elementlerinin D2EHPA emdirilmiş Amberlite XAD-16 reçinelerindeki sorpsiyonunun incelenmesi
Küçük Resim Yok
Tarih
2023
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Ege Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Aktinitlerin NTE' lerden ayrılması, radyoaktif nüklidleri yönetme ihtiyacı nedeniyle nadir toprak endüstrisinde genellikle büyük bir endişe kaynağıdır. İleri teknolojik ürünlerin pek çoğunda kullanılan nadir toprak elementlerinin radyoaktivite içermemesi kaçınılmaz olarak istenilen bir özelliktir. Bu çalışmada solvent olarak D2EHPA (bis (2-etilheksil) fosforik asit) ve polimer destek olarak Amberlite XAD-16 kullanılarak hazırlanan solvent emdirilmiş reçine (SER) in nitrat ortamından Th (IV), Ce (III), La (III) ve Nd (III) ekstraksiyonunun incelenmesi amaçlamıştır. Tek elementli çözeltilerde, Th (IV), Ce (III), La (III) ve Nd (III) alımında başlangıç pH'sinin etkisi incelenmiş, (derişim: 100 mg.L-1, V/m: 25mL/0,1g SER, T: 30 °C, t: 2 saat ) gerçekleştirilen denemelerde en uygun pH; Th (IV) için pH: 2, Ce (III) için pH: 5,46, La (III) için pH: 6,21 ve Nd (III) için pH: 6,01 olarak belirlenmiştir. Th ve La' nın D2EHPA-XAD 16 SER üzerine adsorpsiyonunda adsorpsiyon verilerinin Langmuir ve Freundlich izoterm modelleri ile uyumlu olduğu belirlenmiştir. Hesaplanan maksimum tek tabakalı alım kapasitesi Th için 19,53 mg.g-1 SER ve La için 28,25 mg.g-1 SER dir. Farklı sıcaklıklarda yapılan termodinamik çalışmalar, sorpsiyon işleminin hem toryum hem de lantan iyonları için uygulanabilirliğini ve kendiliğinden doğasını ortaya çıkarmıştır. D2EHPA-XAD 16 reçinenin karışık çözeltideki söz konusu iyonlara karşı ilgisinin Th > Nd >Ce >La şeklinde olduğu belirlenmiştir. Sıyırma çalışmaları, D2EHPA-XAD 16 SER' de adsorbe edilen toryum ve lantanın sıyırma adımında ayrılabileceğini göstermiştir.
Separation of actinides from REEs is often a major concern in the rare earth industry due to the need to manage radioactive nuclides. It is an inevitably desirable feature that the rare earth elements used in many advanced technological products do not contain radioactivity. In this study, it was aimed to investigate the extraction of Th (IV), Ce (III), La (III) and Nd (III) from nitrate medium of solvent-impregnated resin prepared by using bis (2-ethylhexyl) phosphoric acid- D2EHPA as solvent and Amberlite XAD-16 as polymer support. The effect of initial pH on Th (IV), Ce (III), La (III) and Nd (III) uptake in single solutions was investigated, (concentration: 100 mg.L-1, V/m: 25mL/0,1g SER, T: 30 °C, t: 2 hours) the most favorable pH in the experiments; pH: 2 for Th (IV), pH: 5,46 for Ce (III), pH: 6,21 for La (III), and pH: 6,01 for Nd (III). Batch sorption experiments using D2EHPA-XAD 16 particles to remove Th (IV) and La (III) (representing III-valent REEs) ions, performed as a function of various parameters such as contact time, metal ion concentration, temperature etc. The sorption experiments were adjusted to the Langmuir and Freundlich isotherm models. The calculated maximum monolayer uptake capacity were 19,53 mg.g-1 SER for Th and 28,25 mg.g-1 SER for La. Thermodynamic studies at different temperatures revealed the feasibility and spontaneous nature of the sorption process for both uranium and thorium ions. It was determined that the affinity of the D2EHPA-XAD 16 resin towards the mentioned ions in the mixed solution was in the form of Th > Nd >Ce >La. Stripping studies showed that thorium and lanthanum adsorbed on the D2EHPA-XAD 16 SIR can be separated in the stripping step.
Separation of actinides from REEs is often a major concern in the rare earth industry due to the need to manage radioactive nuclides. It is an inevitably desirable feature that the rare earth elements used in many advanced technological products do not contain radioactivity. In this study, it was aimed to investigate the extraction of Th (IV), Ce (III), La (III) and Nd (III) from nitrate medium of solvent-impregnated resin prepared by using bis (2-ethylhexyl) phosphoric acid- D2EHPA as solvent and Amberlite XAD-16 as polymer support. The effect of initial pH on Th (IV), Ce (III), La (III) and Nd (III) uptake in single solutions was investigated, (concentration: 100 mg.L-1, V/m: 25mL/0,1g SER, T: 30 °C, t: 2 hours) the most favorable pH in the experiments; pH: 2 for Th (IV), pH: 5,46 for Ce (III), pH: 6,21 for La (III), and pH: 6,01 for Nd (III). Batch sorption experiments using D2EHPA-XAD 16 particles to remove Th (IV) and La (III) (representing III-valent REEs) ions, performed as a function of various parameters such as contact time, metal ion concentration, temperature etc. The sorption experiments were adjusted to the Langmuir and Freundlich isotherm models. The calculated maximum monolayer uptake capacity were 19,53 mg.g-1 SER for Th and 28,25 mg.g-1 SER for La. Thermodynamic studies at different temperatures revealed the feasibility and spontaneous nature of the sorption process for both uranium and thorium ions. It was determined that the affinity of the D2EHPA-XAD 16 resin towards the mentioned ions in the mixed solution was in the form of Th > Nd >Ce >La. Stripping studies showed that thorium and lanthanum adsorbed on the D2EHPA-XAD 16 SIR can be separated in the stripping step.
Açıklama
Anahtar Kelimeler
Kimya, Chemistry
