Efficacy of Alginate Extracted from Marine Brown Algae (Sargassum sp.) as a Coagulant for Removal of Direct Blue2 Dye from Aqueous Solution

Abstract

<p>The coagulation potential of alginate extracted from marine brown algae, <em>Sargassum sp.</em> for the removal of Direct Blue 2 dye from aqueous solution was studied. Extracted alginate was characterised by Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM) techniques. Batch coagulation tests were carried out by using standard Jar test apparatus to study the influence of initial Ph</p> <div> <p>(4 – 10), coagulant (alginate) dosage (10 – 60 mg l<sup>-1</sup>), initial concentration of dye (100 – 500 mg l<sup>-1</sup>) and calcium dosage (1 – 6 g l<sup>-1</sup>) on removal of dye. The maximum dye removal was observed as 86.1 % at initial dye concentration of 200 mg l<sup>-1</sup>, 6 g l<sup>-1</sup>of calcium dose, 40 mg l<sup>-1</sup>of alginate dose and pH 4. The Sludge Volume Index (SVI) was examined at the maximum dye removal condition and compared with Alum. The kinetic study reveals that the coagulation process for the removal of Direct Blue 2 dye follows second order kinetic model. The obtained results were compared with the literature available on the application of various seaweeds for wastewater treatment methods and their efficiency. Based on the investigation, it is evident that the alginate extracted from <em>Sargassum sp. </em>can be used as an effective novel coagulant for the removal of Direct Blue 2 dye from aqueous solution. </p> </div> <p> </p>