Aktif Karbon Üzerine Perteknetat Oksoanyonunun Denge İzoterm Modelinin Belirlenmesi

Adsorbent olarak aktif karbon kullanılaarak, sulu çözeltierden radyoaktif 99mTcO4- adsorpsiyonunda adsorpsiyon prosesinin mekanizmasını araştırmak için iyi bilinen dört izoterm modeli uygulandı. R2 değerlerine göre, deneysel verilerin dört izoterm modeli için de uygun olduğu bulundu. Ancak, deneysel ve modellerden hesaplanan adsorpsiyon kapasiteleri karşılaştırıldığında, deneysel verilere en uygun izoterm modellerinin Langmuir ve Temkin olduğu görülmüştür. Langmuir izoterm modelinden elde edilen maksimum tek katmanlı adsorpsiyon kapasitesi değeri 3170 µCi.g-1'dir. Uygun bir adsorpsiyon deneyini gösteren boyutsuz ayırma faktörü (RL) değeri 0.126'dır. Ayrıca Freundlich izoterm modelinde, uygun adsorpsiyonu gösteren adsorpsiyon yoğunluğu (n) değeri 1.72'dir. Adsorpsiyon proses ısısı Temkin İzoterm modelinden 724 J / mol olarak ve ortalama serbest enerjinin D-R izoterm modelinden 13.4 J / mol olarak tahmin edilmiştir. Bu verilere göre, adsorpsiyon sürecinin fiziksel adsorpsiyon ile gerçekleştiği söylenebilir. Sonuçlar, aktif karbonun, sulu çözeltilerden radyoaktif 99mTcO4- 'ün uzaklaştırılması için başarılı bir adsorbent olduğunu gösterdi.

Anahtar Kelimeler:

Radyoaktif madde, Aktif Karbon, İzoetrm Modeli, Adsorpsiyon

Determined of Equilibrium Adsorption Isotherm Model Pertechnetate Oxoanion Onto Activated Carbon

Four well-known isotherm models were appropriated to investigate the adsorption process mechanism in the radioactive 99mTcO4- adsorption from aqueous solution by using activated carbon as adsorbent. According to R2 values, the experimental data is found to be suitable for the four isotherm models. However, when the adsorption capacities of the experimental and calculated from models are compared, it has been seen that the isotherm models best suited to the experimental data are Langmuir and Temkin. The maximal monolayer adsorption capacity value founded from Langmuir isotherm model is 3170 µCi.g-1. The dimensionless separation factor (RL) value indicating a favorable adsorption experiment is 0.126. Also from Freundlich Isotherm model, the adsorption intensity (n) value which indicates favorable adsorption is 1.72. The heat of adsorption process was estimated from Temkin Isotherm model to be 724 J/mol and the mean free energy was estimated from D-R isotherm model to be 13.4 J/mol. According to these data, it can be said that the adsorption process is realized by physical adsorption. The results showed that the activated carbon was to be a successful adsorbent for the removal of radioactive 99mTcO4- from aqueous solutions.

Keywords:

Radioactive Substance, Activated Carbon, Isotherm Models,

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