Chitosan nanoparticles on a natural zeolite as an efficient adsorbent for Congo red

摘要

Congo red is a toxic synthetic dye that cannot be readily degraded by conventional methods,thus posing a risk to the environment.The increased use of this dye is mainly due to developments in the textile industry.A possible way to reduce the Congo-red waste is by performing the adsorption processes;therefore,in this study,we used a natural zeolite from Bayah and modified it using chitosan nanoparticles(Na-zeolite@chitosan)to increase its adsorption capacity.The obtained Na-zeolite@chitosan material,which was able to efficiently adsorb Congo red,was further characterized by ultraviolet-visible(UV-Vis)and Fourier-transform infrared(FTIR)spectroscopy as well as by transmission electron microscopy(TEM).A maximum of 98.019% of the Congo red was adsorbed at a concentration of 800 ppm and a pH of 5 for 60 min(the adsorption capacity was 0.00428 mmol/g).Our results exhibit that Congo red adsorption on Na-zeolite@chitosan follows the Freundlich adsorption isotherm and can be described using a pseudo-second-order kinetic model.