Highlights
- 60 % of fluoride was removed from 3 mg/L concentration using encapsulated living and growing algae.
- SEM- EDX and FTIR studies confirmed the biosorption of fluoride on algae.
- Bigger scale implementation of the concept is possible due to very simple separation operation of algae from treated water.
- Freundlich isotherm and first-order kinetics were fitted well.
Abstract
The present study focuses on fluoride removal from the water using encapsulated active growing blue–green algae. Encapsulation of active growing algae as biosorbent provides a unique type of biosorbent that continuously develops new active sites for biosorption and can be separated easily from treated water. The experiment was conducted in batch mode with varying parameters- initial pH, initial fluoride concentration, and different biomass amounts (biosorbent dose). The parameters mentioned above were considered and optimized using response surface methodology (RSM). Additionally, the biosorption study assures 60% removal from 3.0 mg/L of initial fluoride concentration. Furthermore, the process was found to follow the Freundlich isotherm model. The study follows first-order kinetics; further, the intra-particle diffusion and surface biosorption both contribute to the rate-determining step. In addition to that, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) results also confirmed the contribution of algal biomass on fluoride removal.
*Original abstract online at https://www.sciencedirect.com/science/article/abs/pii/S2352186420301206