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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 Cellulose as an eco-friendly material is extensive in the nature. In this study, modified cellulose-based complex particle (MCCP) was produced through hydrothermal carbonization with methacrylic acid in the stirring and sand bath circumstance. The activated modified carbon-based porous particle (AMCCP) was prepared by treating with potassium hydroxide at high temperature, showing higher efficiency in removing neonicotinoids than MCCP. The AMCCP was fully characterized via scanning electron microscopy, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller analysis. The Brunauer-Emmett-Teller analysis showed the prepared AMCCP has smaller aggregated particles with higher surface area than MCCP. The adsorption kinetic and the adsorption isotherm of AMCCP were studied, revealing that the pseudo-second-order kinetic model and the Langmuir model correlated with the experimental data better. The maximum adsorption capacity of AMCCP is 142.36 mg/g for acetamiprid. The adsorption process is spontaneous, favorable, and endothermic in nature. After five regeneration time, the adsorption efficiency of the AMCCP is still over 95%. Highlights • The activated modified cellulose-based complex particle (AMCCP) was synthesized. • The modified reagent methacrylic acid led a higher surface area on AMCCP. • The maximum adsorption capacity of AMCCP was 142.36 mg/g for neonicotinoids removal. • Adsorption isotherm, thermodynamic and kinetic were systematically studied. [ABSTRACT FROM AUTHOR]