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Remediation of
azo dyes by using household used black tea as an adsorbent
Hajira Tahir*,
Muhammad Sultan and Qazi Jahanzeb
Department of Chemistry, University of Karachi-Pakistan.
*Corresponding author. E-mail:
hajirat@uok.edu.pk.
Tel.: 092-333-3621470.
Fax: 092- 21-6832216.
Accepted 21 April, 2009 |
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In the present study used black tea and its
impregnates were used as an adsorbents for the removal of
textile dyes such as methylene blue and malachite green. The
impregnation technique was adopted for the preparation of
metal impregnates. The present study shows that used black
tea and its impregnate exhibit adsorption tendency for the
dyes. By applying batch method, the adsorption process were
carried out at various temperatures ranging from 303 to 318
K ± 2 K under the optimized conditions of concentration,
stay time and amount of adsorbent. Adsorption isotherm
equations such as Freundlich, Langmuir and D-R were applied
to calculate the values of respective constants.
Thermodynamic parameters like free energy (ΔG°), enthalpy
(ΔH°) and entropy (ΔS°) were also calculated. The results
show that used black tea show better adsorption tendency
compared to its Impregnates.
Key words:
Dyes, adsorption, black tea, removal, impregnates. |
