Comparative adsorption studies of alginate-based beads for dye removal / Maisarah Ahmad and Faraziehan Senusi

Toxic dye from textile industry contain harmful constituents that effect human and environment. It can cause lung and liver cancer also interfere the ecosystem of the aquatic life. The dye can be treated by physical method which is adsorption process. Adsorption process is defined as the process where adsorbate (dye) attached to the surface of adsorbent (alginate-based beads) for removal of dye. The adsorbent particularly in solid and the adsorbate is liquid. Many types of adsorbent used to solve the dye problem, one of it is sodium alginate based in the form of immobilized beads. The alginate-based beads are modified with the present of other component such as acid and magnetic compound in order to enhance the adsorption process. The process of adsorption is increase by the surface morphology of the beads is increased to adsorb more matter. Thus, a comparative study on adsorbent alginate-based beads of the literature was conducted. The literature data on types of dyes, process parameter, and characterization studies for the process were reviewed in this work. In addition, kinetic and isotherm model were evaluated in order to observe the activity of the adsorption process. Both removal of cationic and anionic have insignificant value of initial concentration, pH and contact time as the removal of dye due to the various modification of the alginate-based beads adsorbent. The dye removal on these effects depends on presence of binding site, charge of adsorbent and active site. The adsorption of dye removal also influences by the dye functional group and modified adsorbent increase in pore size and internal surface. The isotherm and kinetic model for adsorption process dominant on Langmuir and pseudo-second order respectively.