Equilibrium, kinetic, and thermodynamic study on biosorption of indigo carmine using Hypnea musciformis algae

This work investigated the potentiality of Hypnea musciformis algae as a biosorbent for the removal of indigo carmine dye from synthetic solution. The sorption experiments were performed in batch mode under different parametric conditions like pH, contact time, the average particle size of biosorbent and its dosage, dye solution initial concentration, and temperature. The experimental results confirmed the optimum contact time is at least 25 min and favorable pH of 5 for the biosorption of carmine dye. Langmuir, Freundlich, and Temkin isotherms have been used to test the equilibrium data and found the best fit with the Freundlich isotherm with a regression coefficient (R-2) of 0.992 followed by Langmuir (R-2 = 0.979) and Temkin isotherm (R-2 = 0.94). The analysis of kinetic data revealed Pseudo first order as the best fit. The thermodynamic parameter evaluated confirmed the endothermic nature of indigo carmine dye biosorption process.

Automated summary

This study investigated the potential of Hypnea musciformis algae as a biosorbent for removing indigo carmine dye from synthetic solution. The results showed that the optimal contact time was 25 minutes and the favorable pH was 5. The Freundlich isotherm best fit the experimental data, and the pseudo first order kinetic model described the experimental results the most accurately. The biosorption process was found to be endothermic.