Nano boyutlu sıfır değerlikli demir ile sulu ortamlarda klortetrasiklin giderim mekanizmasının incelenmesi

Bu çalışmada kimyasal indirgeme yöntemi ile hazırlanan nano ölçekli sıfır değerlikli demir (nZVI) ile klortetrasiklinin (CTC) sulu ortamlardaki giderim mekanizması incelenmiştir. Çözelti pH’ı, nZVI dozajı, temas süresi ve reaksiyon sıcaklığı sistematik olarak incelenmiş ve maksimum klortetrasiklin gideriminin gerçekleştiği optimum işletme şartlarında klortetrasiklin parçalanma ürünleri belirlenmiştir. Adsorpsiyon davranışının pH’a bağlı olduğu tespit edilmiş ve klortetrasiklinin maksimum giderim verimi pH 6’ da gerçekleşmiştir. 0,4-0,6 g/L aralığındaki nZVI dozajlarında giderim veriminde önemli değişiklik gözlenmediği için optimum dozaj 0,4 g/L olarak belirlenmiştir. Adsorpsiyon kinetiğinin 2 saat içerisinde dengeye ulaştığı ve yalancı ikinci dereceden hız modeline uyduğu belirlenmiştir.

The evolution of removal mechanism of chlortetracycline by nanoscale zero valent iron from aqueous solution

In this study, the removal mechanism of chlortetracycline (CTC) by nanoscale zero valent iron (nZVI) from the aqueous solutions. Experimental variables such as solution pH, nZVI dosage, contact time and reaction temprature were systematically studied and the degradation products of CTC were determined at optimum operating conditions which provided to maximum CTC removal percentages. Adsorption behavior depended pH and maximum removal of CTC occured at pH 6. The optimum dosage was 0,4 g/L because there was no significant removal efficiency when nZVI dosage was between 0,4-0,6 g/L. Adsorption kinetics exhibited that equilibrium was reached within 2 h following the pseudo-second order model.

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