Conversion of foliar residues of the ornamental species Sansevieria trifasciata into adsorbents: the study of dye adsorption in continuous and discontinuous systems
Abstract The species Sansevieria trifasciata is very widespread around the world both for its ornamental use and profusely spread among religions of African origin. The study analyzed the potential of leaf powder prepared from the residual leaves of the species Sansevieria trifasciata , as a potential adsorbent for methylene blue (MB) removal in a discontinuous system. For the batch study, the equilibrium was reached fast for almost all concentrations after 60 min, obtaining the maximum capacity of 139.98 mg.g − 1 for 200 mg.L − 1 . The increase in temperature disfavored the dye adsorption, with the maximum adsorption capacity of 225.8 mg.g − 1 , observed for 298 K. The thermodynamic parameters confirmed that the adsorption process is spontaneous and exothermic. A direct sloping curve was established for the fixed bed, with breakthrough time (t b ) of 1430, 1130, and 525 min for 100, 200, and 500 mg.L − 1 , respectively. The column stoichiometric capacities (q eq ) and the mass transfer zone lengths ( Z m ) were 60.48, 187.01, 322.65 mg.g − 1, and 8.81, 11.28 and 10.71 cm, for concentrations of 100, 200, and 500 mg.L − 1 , correspondingly. Furthermore, in a mixture of several dyes, the adsorbent obtained the removal of 51% of the color.