Removal of fluoride from aqueous solution using algal bio-adsorbent

Abstract

This is a research on adsorption of fluoride from aqueous solution by using algae as bio-adsorbent. The parameters to study on this research were initial concentration of fluoride solution, temperature of adsorption and pH of fluoride solution. The effect of initial concentration of fluoride solution towards algae-sorption system showed a trend of higher fluoride removal efficiency with higher initial concentration of fluoride. In this study, 10 mg/L of initial concentration of fluoride had 70 % efficiency of fluoride removing while 2mg/L of initial concentration of fluoride had 56.27 % efficiency. Influence of pH of fluoride solution did give a significant result where acidic solution would trigger the algae-sorption system to remove fluoride. Besides that, during the finding of temperature effect, 40 degree Celsius (°C) was the optimum temperature to have high percentage of removing fluoride. The temperature range was from 20 – 60 °C. In adsorption equilibrium study, experimental data best fitted into Langmuir isotherm. Its relative good correlation coefficient, R2 was 0.9798. Furthermore, the data fitted well in pseudo second order which indicated that this algae-sorption system was a second order reaction. The R2 values for all the initial concentration of fluoride were 0.9336 till 0.9991 except for 4 mg/L of initial concentration of fluoride had a lower value which was 0.4129.