Using Gin adsorption model for assessing the influence of algal powder bleach process in Cu(II) adsorption

摘要

The Cladophora and Spirogyra algae examined in this study belong to the Chlorophyta division. Macro filamentous algae, which are widespread in fresh water worldwide, have high potential to be developed as biological materials because of their large biomass and availability. In this study, we collected fresh algae from where they grew and produced bleached and unbleached algae powder using to adsorb Cu(II) ion solution. After the biosorption process, we noted the following four significant findings: (i) The functional groups and binding sites in the produced algae powder were affected, causing variations in the amount of copper adsorbed. The variations resulted from differences in the cell structure, the cell wall thickness of Cladophora and Spirogyra algae, cell composition, and the types and amount of epiphytic algae. (ii) Common bleaching procedures using glacial acetic acid influenced the binding sites of the functional groups and the biomass of the produced powder. Because of the bleaching, the amount of copper adsorbed by the Cladophora powder declined by 14.2%, and by 15.7% for Spirogyra powder. (iii) The carbonyl and hydroxyl groups of unbleached powder were the main elements affected during the bleaching procedures. Examining whether the biosorption experiment results fit Gin's biosorption model, we found that the biosorption amount and equilibrium reaction of the two bleached algae powders were inferior to that of the unbleached algae powders. (iv) The bleaching procedure using glacial acetic acid was not suitable for producing algae powder to use as an adsorbent for metal ions.