Synthesis of chitosan/hexagonal boron nitride composites as an alternative adsorbent and the use in adsorption of Reactive Blue 49 dye

In this study, composites with different compositions were synthesized using chitosan and hexagonal boron nitride (hBN) to use as an adsorbent, and these composites were used in the adsorption of Reactive Blue 49 (RB 49) dye from aqueous solutions. Composites were synthesized for chitosan/hexagonal boron nitride (c/hBN) at the ratios of c/hBN:100/0, c/hBN:75/25 and c/hBN:50/50 as the percent by mass of chitosan and hBN in the composition of the composites. Composites were characterized with scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. The pH, time, adsorbent dosage, dye concentration and temperature parameters of the adsorption processes studied with the synthesized composites. According to the results; the highest removals were obtained at pH 4 for c/hBN:100/0 and c/hBN:75/25 composites, and at pH 3 for c/hBN:50/50 composite. Adsorption processes were followed for 240 minutes. It was determined that the composites had the highest adsorption capacity at 0.3 g/L adsorbent dosage. When the adsorption processes were examined in terms of kinetics, the processes showed compatibility with the pseudo second order and the intraparticle diffusion model. In adsorption equilibrium studies; the processes are explained by the Freundlich isotherm model. In thermodynamic studies; it has been determined that the adsorption processes are endothermic and occur spontaneously. As a result; it has been stated that c/hBN composites synthesized in different compositions can be used in the adsorption of RB 49 dye from aqueous solutions.