Continuous Biosorption of Co (II) onto Mg-Modified Sargassum sp. Brown Algae in a Fixed Bed Column

In this research, the potential of Sargassum sp. brown algae was studied to adsorb cobalt from aqueous solutions in a fixed bed column. The effects of key operating parameters, including feed flow rate (۱–۴ mL/min), bed height (۴–۹ cm), and inlet cobalt concentration (۵۰–۱۵۰ mg/L), on uptake were investigated. FTIR analysis was performed to identify the vibrational variations associated with the surface functional group peaks. The FTIR tests showed that hydroxyl, amine, amide, methylene and carboxyl functional groups may have the greatest contribution in the ion exchange mechanism. Moreover, SEM analysis was conducted to investigate the morphological variations in the biosorbent due to the sorption process. Under the studied conditions, the maximum adsorption in the column was achieved at a flow rate of ۱ mL/min, a bed height of ۹ cm, and an initial influent concentration of ۱۵۰ mg/L, reaching ۷۹.۸۳ mg/g. Adsorption breakthrough curves were modeled using Thomas, Yoon-Nelson and Adams–Bohart models. Among the evaluated breakthrough models, the Thomas model provided the most suitable description of Co(II) adsorption behavior, yielding a maximum adsorption capacity of  qTh=۸۱.۹۳ mg/g and a Thomas rate constant of kTh=۱.۱۵×۱۰−۵ L/min.mg. These results suggest that Sargassum sp. can be considered a promising and efficient option for cobalt removal from aqueous solutions in water treatment processes.

کلیدواژه ها:

Biosorption ، Cobalt ، Sargassum sp. brown algae ، Mg-modification ، Breakthrough curve ، Fixed bed column