Removal of Methylene Blue from Aqueous Solution by Application of Plant-Based Coagulants †

Abstract

Five different plant-based coagulants were used with the objective of removing methylene blue (MB) color aqueous solution. The plant-based coagulants were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and Brunauer–Emmett–Teller (BET) which showed that these materials had high porosity and could adsorb the contaminant MB from the aqueous solution. To increase the efficiency of the plant-based coagulants, bentonite was applied as a flocculant. Results showed MB removal of 90.9%, 91.9%, 91.4%, 86.9% and 88.9%, respectively, for seeds of Chelidonium majus L., Dactylis glomerata L., Festuca ampla Hack., Tanacetum vulgare L. and rachises of Vitis vinifera L. In conclusion, plant-based coagulants mixed with bentonite are a biologic, sustainable and cheap alternative for MB removal.