Adsorption of Humic Acid on Different Adsorbents
Humic acid is present in waters and soil. Some researches showed that humic acid may be source of smell and colour in water and may form some complexes with heavy metals. Therefore it is necessary to remove humic acid from waters and to understand the removal mechanism.
In this study, three activated carbons were used as adsorbents for the removal of humic acid from aqueous solution.
The adsorption data were analyzed using the Langmuir and Freundlich isotherms. The results indicated that the Langmuir isotherm was found the represent the adsorption data better. The pH values of humic acid solutions affected the adsorption capacity of the adsorbents used in the study.
Very little information is available on the kinetics and thermodynamic aspects of adsorption of humic acid on the different adsorbents. Therefore kinetic and thermodynamic experiments were carried out.
The initial rate of adsorption of humic acid was fast. Adsorption rate data were analyzed by the Lagergren equation and the adsorption rate constants for three activated carbons were calculated. The intraparticle diffusion coefficients for all the adsorbents were also calculated. Both boundary layer and intraparticle diffusion played important roles in the adsorption of humic acid.
Thermodynamic parameters such as ΔG0, ΔH0 and ΔS0 were calculated and the adsorption of humic acid on three adsorbents was found to be endotermic and spontaneous.
The effect of humic acid on the adsorption of Cr (VI) was also studied. The results showed that the precences of humic acid increased adsorption of Cr (VI).
The data obtained from batch studies show the adsorption capacity of an adsorbent. However, it is necessary to study the adsorbent-adsorbate systems in column processes. Therefore, column experiments were carried out in this study. Column capacities of the adsorbents used in the study were found to be higher than batch experiments.
ÖSKEN İpek
Danışman :Prof. Dr. Ayşe YUSUFOĞLU ve Prof. Dr. Turan ÖZTÜRK
Anabilim Dalı :Kimya
Programı :Organik Kimya
Mezuniyet Yılı :2009
Tez Savunma Jürisi :Prof. Dr. Ayşe YUSUFOĞLU
Prof. Dr. Turan ÖZTÜRK
Prof. Dr. Süleyman TANYOLAÇ
Prof. Dr. Nükhet ÖCAL
Prof. Dr. Zuhal TURGUT
Prof. Dr. Mehmet S. EROĞLU
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