Kinetics and Equilibrium of Mercury Sorption by Three Different Types of Live Algae

Abstract

The kinetics and equilibrium of experimental data of mercury (II) sorption using three different macrophytes E. crassipes, E. azurea and S. ariculata were analyzed. From the kinetic models used, the model 1, which considers the surface area of constant sorption, presents the coefficient of determination, R², closer to the unit (0.97). Already, in the liquid phase, the best fit of the experimental data was obtained for model 2 (R²=0.96), which considers the variable surface area. The calculated values for the determination coefficients indicate that the Redlich-Peterson isotherm best describes the equilibrium (R²=0.79). The results show that the macrophyte S. ariculata surface area, which presented the highest adsorption potential (15.77x10^-4m².g^-1), was far below those found in the best adsorbents. However, considering the large volume of adsorbent material required in an industrial plant and the low cost of the analyzed adsorbents, it is considered that the macrophytes investigated have a considerable potential for the removal of mercury from wastewater.

Keywords:
Sorption; Mercury; Heavy Metal; Equilibrium; Kinetic