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[Display omitted] • Removal of organophosphorus pesticides from tea infusion was first reported. • The removal rate of pesticides by modified materials was greatly improved. • Hydrophobic interaction played a dominant role in the adsorption process. • There were no significant changes in tea infusion quality after adsorption. The abuse of organophosphorus pesticides (OPPs) in tea planting makes it easy to transfer from tea into its infusion, bringing potential health risks to consumers. Thus, it is essential to adopt reliable techniques to remove OPPs from tea infusion. In this study, three treatment methods were used to modify carbonized bacterial cellulose (CBC) to improve its adsorption performance. Among them, CBC treated by hydrazine hydrate (N -CBC) had the best adsorption effect, whose removal rate for dicrotophos is 13 times that of CBC. The in-depth study of adsorption mechanism proved that hydrophobic interaction dominated the adsorption of OPPs onto N -CBC. The pseudo-second-order kinetic model and Langmuir isotherm model were more suitable to describe the process. Additionally, there were no significant changes in tea infusion quality after N -CBC treatment. This work clarifies that N -CBC benefitted from simple preparation method, excellent adsorption performance and unique adsorption mechanism has potential applications in tea infusion. [ABSTRACT FROM AUTHOR]

[Display omitted] • CBC were prepared by direct calcination of BC under different temperatures. • CBC-350 can remove multiple pesticides in tea infusions quickly and efficiently. • The CBC-350 also has excellent adsorption capacity compared to other adsorbents and can be reused at least five times. Soaking tea leaves make tea consumers exposure to pesticide residues more easily. However, there are few studies on the removal of pesticides in tea infusions. Therefore, a low-cost carbonized bacterial cellulose material was prepared by direct calcination method, and used to remove multiple pesticides in tea infusions quickly and efficiently. CBC-350 has the best removal efficiency for 9 pesticides and then screened the best adsorption conditions. The adsorption isotherm experiment was carried out and indicated that the adsorption process was in consist with the Freundlich model. The thermodynamic parameters are also calculated. Moreover, the adsorption mechanism was discussed, which suggests that π-π interaction and hydrophobic action are the driving force during the adsorption process. Exhilaratingly, the CBC-350 also has excellent adsorption capacity compared to other adsorbents and can be reused at least five times. [ABSTRACT FROM AUTHOR]

Abstract In this study, nano zirconium carbide (n-ZrC) was synthesized by preceramic polymers method, and it was used to adsorb emodin and physcion from solutions for the first time. The prepared material was characterized by various technologies. The adsorption experiment was carried out to investigate the emodin and physcion removal performance. The results indicate that the pseudo-second-order kinetic model and the Langmuir model correlated satisfactorily to the experimental data, and the thermodynamic parameters are also calculated. Especially, n-ZrC can remove >95% of emodin or physcion in a minute under the optimal conditions, it is the fastest adsorption rate compared to other commonly used adsorbents (commercial zirconium carbide, activated carbon, C18, PSA, GCB and florisil). The adsorption mechanism was discussed, which suggests that Van der Waals' forces are the primary driving power during the adsorption process. Moreover, n-ZrC is stable at different pH and it can be reused at least fifteen times. Graphical abstract Unlabelled Image Highlights • Nano zirconium carbide (n-ZrC) was synthesized and used to adsorb medicine (emodin and physcion) for the first time. • N-ZrC can remove >95% of emodin or physcion in 1 min, far faster than other commonly used adsorbents. • The Van der Waals' forces have been proved to be the primary driving power during the adsorption process. • The n-ZrC is stable at various pH it can be reused fifteen cycles. [ABSTRACT FROM AUTHOR]