Biosorption of a crystal violet using equisetium telmateia ehrh

Abstract

In this study, cationic dye removal from synthetic wastewater by the biosorption method was investigated in batch mode. Equisetium telmateia Ehrh was used as a biosorbent. In order to measure the biosorption capacity of the dyestuff, the variation of parameters such as adsorbent dose, initial dyestuff concentration, pH, and temperature were taken into account. By using the experimental data obtained, compatibility with isotherm models such as Langmuir, Freundlich, Temkin, Sips, Toth, and Khan was tested. The relationship between biosorbent and dyestuff was investigated by looking at the adsorption kinetics of Lagergren, Ho, and Elovich. Experimental data showed compatibility with the Sips equation from the isotherm models, while the kinetic models showed the highest compatibility with the Ho equation. Optimum conditions of the system; For 10 g/L adsorbent dose, 150 rpm mixing speed, 100 mg/L initial dyestuff concentration, 360 min reaction at 25⁰C temperature and 6.2 pH, the removal efficiency was 87.02% and the adsorption capacity was 8.7 mg/g. In addition, thermodynamic parameters were examined and activation energy (Ea) was calculated as 14.009 kJ/mol for optimum conditions. However, the enthalpy change (∆H*) was 11.488 kJ/mol, while the entropy change (∆S*) was-0.231 kJ/mol. The surface morphology of the adsorbent was characterized by FTIR. The results indicated that Equisetium telmateia Ehrh could be employed as an alternative to commercial biosorbents in wastewater treatment for the removal of color and dyes.