Kinetics and Isotherm Studies for Methylene Blue Dye Removal Using Carbon Derived from Bulb of Zephyranthes citrina

Abstract

The foremost objectives of the present research work is to remove the methylene blue dye from wastewater samples using carbon derived from Zephyranthes citrina (ZC)  bulb by kinetics and isotherm studies.  The present studies open up an innovative approach and investigate porous, efficient raw carbon from the ZC, which was used as an adsorbent. The well-dried and finely powdered ZC bulb was carbonized at a temperature of 900°C. The carbonized crude ZC sample was characterized by FT-IR, UV-visible, Scanning Electron Microscopy (SEM), and X-ray diffraction techniques, and their adsorption potential to remove the basic methylene blue (MB) dye from an aqueous sample. Adsorption studies comprise both adsorption isotherm and kinetic methods. The processes were carried out with diverse adsorbate concentrations and adsorbent quantities at various time intervals in the batch mode process. Kinetic models of Lagergren first order, pseudo second order and intra particle diffusion were used to assess the kinetics and adsorption mechanism. The results revealed that the adsorption process follows the first order kinetic model of Lagergren. Based on the results obtained, the maximum removal (81%) of the dye was achieved as a solution containing 50 mg of the 50 ml dye at 3 hours for methylene blue. The results indicated that the bulb of ZC carbon is a proficient adsorption material and is also used as a cost effective alternative that can absorb dye from an aqueous solution without activation treatment.