Application of Azolla rongpong on biosorption of acid red 88, acid green 3, acid orange 7 and acid blue 15 from synthetic solutions [An article from: Chemical Engineering Journal]

This digital document is a journal article from Chemical Engineering Journal, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Azolla rongpong, a fresh water macro alga, was tested for its ability to remove acid dyes (acid red 88 (AR88), acid green 3 (AG3), acid orange 7 (AO7) and acid blue 15 (AB15)) separately from aqueous solution. The sorption isotherms, obtained at different ranges of pH (2-3.5) and temperature (25-35^oC), were fitted using Langmuir, Freundlich, Redlich-Peterson and Sips models. The maximum dye uptake of 83.33mg/g was obtained for AG3 at optimum conditions of pH (2.5) and temperature (30^oC) according to Langmuir isotherm model. Various thermodynamic parameters such as @DG^o, @DH^o and @DS^o were calculated indicating that the present system was spontaneous and endothermic process. The pseudo-first and -second order kinetic models were also applied to the experimental kinetic data obtained during biosorption of four acid dyes and high correlation coefficients favor pseudo-second order model for the present systems. Since A. rongpong performed very well in the case of AG3 biosorption compared to other dyes, AG3 was selected as the model dye for examining the potential of A. rongpong in continuous biosorption. A glass column (2cm i.d. and 35cm height) was used to conduct continuous experiments. At 25cm (bed height), 5mL/min (flow rate) and 100mg/L (initial dye concentration), A. rongpong exhibited AG3 uptake of 84.87mg/g. The experimental data were analyzed using Bed Depth Service Time and Thomas models and the model parameters were evaluated.