Use of Typha angustifolia L. as Biosorbent to Remove Chloramphenicol in Aqueous Samples

The identification and quantification of different contaminants in natural waters have been widely disseminated in scientific journals. In the last two decades, removal from aqueous samples of drugs and their metabolites, also called emerging contaminants, have been highlighted. The problem of their existence in the environment, besides its persistence, is related to the occurrence of more resistant bacteria, being a serious risk to health. Thus, the objectives of this project were characterization of cattail leaves, Typha angustifolia L. in natura, and its application for the removal of the antibiotic chloramphenicol in aqueous samples. The material was characterized by Fourier Transform in the Infrared Region (FTIR), Point of Zero Charge (PZC), Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), as well as surface area measurements (Brunauer, Emmett, Teller-BET). Batch experiments were performed considering the influence of pH, contact time and analyte concentration, whose supernatant solution was quantified by Ultra Performance Liquid Chromatography (UPLC). Both results, regarding FTIR spectrum and NMR analysis, corroborated by identifying functional chemical groups that promote interaction between biosorbent and analyte. The pHPZC, estimated around 5.75, was considered to choose the ideal pH of the medium that favors adsorption. By means of SEM images, the material was characterized by parallel plates with large number of channels (heterogeneous surface). Type II isotherm was obtained from BET method, with low surface area, nonporous or macroporous, mono and multilayer adsorption. Pseudo-second order was the model that best fit the adsorption kinetics, while for determining the maximum capacity, the Freundlich model showed the highest agreement.