A Green Technology for the Removal of Emerging Pollutant Triclosan Using Immobilized Biomass of the Cyanobacterium Spirulina platensis.

The pervasive presence of triclosan (TCS) in the aquatic system poses a serious environmental concern due to its toxicity and persistence. The primary reason is the inefficient removal of TCS from the sewage treatment plant, which contaminates the water body. Biological treatment is one of the emerging, eco-friendly, and cost-effective methods generally employed for removing pollutants, including TCS. In the present work, a cyanobacterium, Spirulina platensis, free algal cells, and algal cells immobilized in alginate beads were utilized as biosorbents to evaluate the biosorption of TCS in aqueous solution. Removal efficiency, kinetic modeling, scanning electron microscopy (SEM), and reusability of biomass were assessed. A maximum removal efficiency of 100% was achieved in 48 h when exposed to a 2 mg L-1 TCS concentration by Spirulina alginate beads (SAB) compared to free algal cells. SAB exhibited a higher biosorption rate and 93.48% removal efficiency after four successive treatment cycles. Kinetic study revealed that the TCS adsorption followed a pseudo second-order kinetic model, as indicated by a higher correlation coefficient value. The SEM showed the changes in surface topography of the biosorbent. Thus, this study provides new insights into the effectiveness and reusability of alginate-immobilized cyanobacterial systems for the removal of TCS, highlighting their potential for sustainable water treatment applications.