Synthesis, characterization, and regeneration of an inorganic–organic nanocomposite (ZnO@biomass) and its application in the capture of cationic dye

Despite the efficiency of ZnO nanoparticle (NPs) composite adsorbents in the adsorption of various pollutants, there is presently no report on the combo of ZnONPs with biomass for adsorption. Besides, there is a dearth of information on the biosorption of celestine blue (CEB), a dye used in the nuclear and textile industry. In this study, biogenic-chemically mediated synthesis of a composite (ZnO@ACP) was prepared by the impregnation of ZnONPs onto Ananas comosus waste (ACP) for the adsorption of CEB. The SEM, EDX, FTIR, XRD, BET, and TGA characterizations showed the successful presence of ZnONPs on the biomass to form a nanocomposite. The uptake of CEB was enhanced by the incorporation of ZnONPs on ACP. A faster CEB adsorption onto ZnO@ACP (120 min) compared to ACP (160 min) was observed. The Langmuir (R(2) > 0.9898) and pseudo-second-order (R(2) > 0.9518) models were most appropriate in the description of the adsorption process. The impregnation of ZnONPs onto the biomass enhanced the spontaneity of the process and displayed endothermic characteristics. High CEB desorption of 81.3% from the dye loaded ZnO@ACP as well as efficient reusability showed the efficacy of the prepared nanocomposite for CEB adsorption.