Abstract
The development of low-cost solid sorbents with high sorption capacities has gained a major interest. In the current study, amines modified natural fibers were prepared via the hydrothermal method by using ethylenediamine and hydrazine as modifiers and fibers obtained from natural Populus tremula as raw materials. Unmodified and amines modified fibers were characterized and were employed in batch mode experiments for the biosorption of Acid Blue 25 (AB25) as a pollutant model from water samples. The studied fibers were proven to be a lignocellulosic fiber with a 12% lignin content in addition to a high content of cellulose (60%). The coordinating sites were 0.578 and 0.647 mmol.g(-1) for the ethylenediamine-fiber and the hydrazine-fiber. The registered adsorbed amounts of AB25 follow the order: ethylenediamine-fiber (67 mg.g(-1)) > hydrazine-fiber (48 mg.g(-1)) > unmodified fiber (22.33 mg.g(-1)). The fitting of the experimental data to theoretical equations reveals that thebiosorption complies well with the pseudo-second-order for the amines modified fibers. Fibers were easily separated from the water after biosorption of the dye, demonstrating that it has great potential as a material for water purification. (C) 2017 Elsevier B.V. All rights reserved.