Urfa taşı, düşük maliyetli, yerel olarak bol bulunan, yüksek verime sahip ve çevreye duyarlı bir adsorbent olarak kullanılabileceği düşünülerek, atık sudan boyaları uzaklaştırmanın güncel pahalı yöntemlerine alternatif bir adsorbent olarak incelenmiştir. Bu çalışma ile Urfa taşının sentetik olarak hazırlanmış atık sulardan metilen mavisi (MB) boyası uzaklaştırma potansiyeli araştırılmıştır. Laboratuvar deneyleri kesikli olarak yürütülmüştür. Urfa taşının MB sorpsiyonu performansı, dozaj (0.1, 0.25, 0.5 ve 1 g) ve başlangıç konsantrasyonları (5, 10, 20, 30 ve 40 mg L^-1) ile hesaplanmıştır. Deneyler farklı pH (3, 5, 7, 8, 8.98 ve 11) değerleri için de gerçekleştirilmiştir. Adsorpsiyon oranlarının hesaplanması için iki kinetik model (yalancı ikinci mertebeden ve por difüzyonu) kullanılmıştır. Ayrıca Lagergren eşitliği ile adsorpsiyonun mekanizması da incelenmiştir. Deneysel veriler, Langmuir, Freundlich ve Tempkin izoterm modelleri kullanılarak analiz edilmiştir. Elde edilen neticede Metilen mavisi boyasının Urfa Taşı üzerinde adsorpsiyonunun Langmuir izotermine tam uyum gösterdiği, kısmen Tempkin izotermine uyduğunu göstermiştir. Yalancı ikinci mertebe kinetiği ve por difüzyonu mekanizmasının adsorpsiyonun kinetiğine uygulanabileceği ve intrapartiküler difüzyon hızının etkili mekanizma olduğu anlaşılmıştır. Adsorpsiyonun kendiliğinden meydana gelme eğiliminde olduğu, Urfa taşının metilen mavisine doğal ilgisinin bulunduğu tespit edilmiştir. Urfa taşının doğal, ekonomik ve çevreci bir adsorbent olarak kullanılabileceği anlaşılmıştır.

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