Search

The overuse of thiamethoxam (THM) has threatened the survival of living organisms and it is necessary to find an environmentally friendly material to remove THM frequently detected in water. Biochar prepared from cow manure modified with ZnCl 2 (Zn-CBC) was used to remove THM. Compared to the unmodified cow manure biochar (CBC), the removal ratio of THM by Zn-CBC was enhanced 35 times. In the mechanistic analysis, SEM and BET showed that Zn-CBC had a good pore structure and its specific surface area (166.502 m2 g−1) increased to 17 times that of CBC, indicating that Zn-CBC had good pore adsorption properties. The adsorption kinetic and isotherm implied that the main mechanism was chemisorption including π-π interaction and H-bonding. Furthermore, the stable graphitized structure of Zn-CBC allowed for efficient adsorption and reusability. In addition, this study constructed an intelligent prediction model using batch experiment data, and the high R2 (0.978) and low RMSE (0.057) implied that the model could accurately and quantitatively predict the adsorption efficiency. This paper provides a novel perspective to simultaneously remove the neonicotinoid insecticides and realize the resource utilization of cow manure. [Display omitted] • ZnCl 2 -modified biochar derived from cow manure was used to adsorb THM. • The specific surface area of Zn-CBC was 17 times that of CBC. • Zn-CBC had a stable adsorption capacity in a wide pH range. • The main adsorption mechanisms are pore filling, π-π conjugation and H bonding. • Quantitative prediction of THM removal ratio by artificial intelligence. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of S-doped biochar (WPB-S) and N-doped biochar (WPB-T) from watermelon peel. • Investigation of WPB-S and WPB-T as an improver for biogas production from C. myrica. • The supreme biogas production (623 mL/g VS) was achieved using 50 mg/L of WPB-S. • Smaller total pore volume, S-functional groups and higher conductivity of WPB-S may play a key role in enhancing DIET. • A new direct interspecies electron transfer mechanism of WPB-S and WPB-T has been proposed. Although it was suggested that adding biochar to an anaerobic reactor may aid in digestion, its function has not been formally established. It has been suggested that anaerobic digestion (AD) is dominated and participated in by direct interspecies electron transfer (DIET). This study assessed the efficiency of S-modified biochar (WPB-S) and N-modified biochar (WPB-T) using Triethylenetetramine (TETA) derived from watermelon peels biomass as an additive for the production of biogas from brown algae cystoceira myrica (C. myrica) either co-digested or individually with WPB-S or WPB-T. BET, FTIR, TGA, XRD, XPS, SEM, and EDX were used to characterize the prepared biochars. FTIR analysis confirmed the establishment of S and N groups on the surface of biochar. The modified Gompertz kinetic model fits the investigational data satisfactorily, with R 2 ranging between 0.907 and 0.990. Adding WPB-S at doses of 50 mg/L to C. myrica considerably enlarged the biogas yield (623 mL/g VS) compared to all other treatments. Finally, according to RSM study, the maximum biogas production (585.53 mL/g VS) was achieved for C. myrica and WPB-S treatment after 48 days of contact time using 50 mg/L WPB-S dose. The mechanism of DIET has been studied in detail, confirming that WPB-S can support electron transfer and conversion of CO to CH 4. DIET mechanism could be explained in new ways depending on the conductivity, XPS, FTIR and BET findings which confirm that S-functional groups, S% in the surface of WPB-S and smaller total pore volume are the main reason for higher biogas production. [ABSTRACT FROM AUTHOR]

Imidacloprid (IMI), as the most-consumed pesticide, has posed a severe threat to the water ecosystem due to its recalcitrance and inefficient elimination in the traditional wastewater treatment. Herein, a heterogeneous electro–Fenton (EF) system coupled with 3D–MoO 2 –porous biochar (PBC) cocatalytic electrodes, abbreviated as 3D–MPE–EF, is initially applied to promote the elimination of IMI in the agrochemical wastewater from pesticide production. The elimination rate of IMI by 3D–MPE–EF system is 18.15 times higher than that by traditional EF system at pH 7.0. The utilization of 3D–MoO 2 –PBC electrodes sufficiently compensates for inherent deficiencies of traditional EF system. The circular utilization of Fe is also addressed by 3D–MoO 2 –PBC cocatalytic electrodes to reduce the consumption of Fe2+ and the deposition of iron mud. Through comparison, MoO 2 is considered the most appropriate cocatalyst in terms of the reutilization of Fe and degradation of IMI. Eight mechanisms are identified in the degradation pathways of IMI by UPLC–Q–TOF–MS. The ecotoxicities of IMI are remarkably attenuated in the 3D–MPE–EF system. This study provides insights into the roles of 3D–MoO 2 –PBC cocatalytic electrodes in the enhanced elimination of IMI in heterogeneous EF system. [Display omitted] • The IMI removal by EF system is greatly enhanced by 3D–MoO 2 –PBC electrodes. • The alkaline elimination of IMI is promoted by 3D–MoO 2 –PBC electrodes. • The reutilization of Fe is addressed by MoO 2 to reduce the deposition of iron mud. • Eight plausible degradation mechanisms of IMI were identified in 3D–MPE–EF. • The ecotoxicity of IMI were progressively attenuated in the 3D–MPE–EF system. [ABSTRACT FROM AUTHOR]