Application of Chitosan-Dendrimer PPI Hybrid in Direct Dyes Removal: Optimization by RSM, Kinetic and Isotherm Studies

In this paper, the application of Chitosan-Dendrimer PPI (CS-PPI) hybrid as a biopolymer adsorbent for the decolorization of colored textile effluent containing direct dyes was reported. A Response Surface Methodology (RSM) was applied to optimize the operating variables of the decolorization process. The results from the adsorption experiments revealed that the optimal conditions for dye removal were: pH 2; dye concentration 75 mg/l; duration time 30 minutes and temperature 40 ⁰C. The dye removal values of 5555.55 mg/g and 6134.97 mg/g were achieved with DR23 and DR81, respectively. The kinetic absorption data for used direct dyes fitted well to pseudo-second order kinetic model. Furthermore, adsorption isotherm study indicated that dyes adsorption was correlated reasonably well by Langmuir isotherm model. The results from this paper demonstrated that CS-PPI can be employed as an affective biopolymer with high potential for direct dyes removal from colored textile effluents.