Insights into the performance and mechanism of a reinforced lignocellulosic sorbent fabricated from sawdust biomass for multi-tasking application in enrofloxacin removal and monitoring

Abstract

Natural lignocellulose-based materials have numerous strengths such as abundance, cheap price and biodegradability, which indicates a brilliant prospect for environmental protection. This work aimed to design an efficient sorbent (NaSS-PSD) by pine sawdust (PSD) for the surveillance and management of enrofloxacin (ENR). In the study, sodium styrenesulfonate (NaSS) was chosen as an effective monomer to ameliorate the performance of PSD by graft copolymerization. The removal of ENR by NaSS-PSD was enhanced in comparison with the ungrafted ones under investigated conditions. Pseudo-second-order and Temkin were the best-fitted models to describe the adsorption behavior. For the first time, NaSS-PSD was employed as a novel extractant of solid-phase extraction (SPE) and dispersive solid-phase microextraction (DSPME) to develop accurate, eco-friendly and economic analytical techniques for trace ENR determination. Good linearity and reproducibility were obtained. The limits of detection were 0.41 μg/L for DSPME-HPLC-DAD technique and 0.15 μg/L for SPE-HPLC-DAD technique. These two methods exhibited satisfying practicability when applied to quantify ENR residue in real waters. The study on interfacial interaction mechanism and preferential binding sites suggested that hydrogen bond and π-π interactions took the primary responsibility. Our work provides a good perspective for tailoring natural lignocellulosic biomass to be alternative adsorbents for emerging pollutants.