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Divalent cadmium ions in the water environment are a serious threat to human health. The purpose of this study is to develop a biodegradable bio-adsorbent based on bagasse lignin and can effectively adsorb cadmium ions. In this study, it was found that the thiol amino co-grafted lignin nanospheres (TALNPs) had been successfully prepared by the Mannich reaction system, and the performance tests indicate that TALNPs have good adsorption potential. The evaluation experiment shows that factors such as pH value, dosage, time, initial concentration, and temperature significantly affect the ability of TALNPs to adsorb cadmium ions. The simulation calculation of isothermal adsorption experiment shows that the adsorption of cadmium ions follows the Langmuir model, and the adsorption kinetics is pseudo-second order. Compared with unmodified lignin, the ability of TALNPs has increased by about 3.5 times. Using XPS to analyze the structure of TALNPs in the adsorption and desorption process shows that only the bridge bond changes, indicating that it is a relatively stable adsorbent and can be reused. In general, the design strategy of thiol-amino co-grafting to modify lignin nanospheres can enhance the adsorption of cadmium ions, and also provide a new way for the development and utilization of bagasse lignin. [Display omitted] • Thiol-Amino co-grafting lignin nanospheres was successfully prepared. • Modified lignin has good adsorption potential. • The adsorption capacity of cadmium ions is increased approximately 3.5 times. • The max adsorption capacity reaches 183.36 mg/g and follow as Langmuir model. [ABSTRACT FROM AUTHOR]

To assess the application potential of sewage sludge biochar produced by industrial-scale pyrolysis (ISB), the release characteristics of nutrients (NH 4 +, PO 4 3−, K, Ca, Mg and Fe) and heavy metals (Mn, Cu, Zn, Pb, Ni and Cr) were investigated. Their release amounts increased with decreasing initial pH and increasing solid-liquid ratios (R S-L) and temperature. The release types of NH 4 +, K, Mg, and Mn were diffusion/dissolution, while those of Cu, Zn, Pb, Ni, and Cr were diffusion/resorption. The release types of PO 4 3− and Ca varied with initial pH and R S-L , respectively. The chemical actions played dominant roles in their release, while particle surface diffusion and liquid film diffusion determined the rates of diffusion and resorption phases, respectively. The release of NH 4 +, PO 4 3−, K, Ca, Mg, Mn and Zn was a non-interfering, spontaneous (except PO 4 3−), endothermic, and elevated randomness process. The release efficiency of NH 4 +, PO 4 3− and K met the Chinese standard for slow-release fertilizers, while the total risk of ISB was low. The eutrophication and potential ecological risks of ISB were acceptable when the dose was less than 3 g L−1 and the initial pH was no lower than 3. In conclusion, ISB had potential as a slow-release fertilizer and adsorbent. • Release behavior of nutrients and HMs significantly relied on initial pH, R S-L and T. • Pseudo-secondary kinetic model better described the release of nutrients and HMs. • Their release was a non-interfering, spontaneous, endothermic and entropic process. • Release rates and HSEI confirmed ISB's potential as a slow-release fertilizer. • ISB could be as an adsorbent for water treatment (initial pH ≥ 3, dose <3 g L−1). [ABSTRACT FROM AUTHOR]

• Composition and antibiotic resistance of FCB were investigated in WWTP. • Sedimentary tank contributed most to the removal of FCB. • The dominant FCB belonged to Escherichia coli and Klebsiella pneumoniae. • Biological unit significantly increased antibiotic resistant rate of FCB community. • Health risk caused by Klebsiella pneumoniae should be emphasized after WWTP. The dynamics of the composition and antibiotic resistance of the fecal coliform bacteria (FCB) in a typical wastewater treatment plant (WWTP) were investigated concerning the seasonal changes. Results showed that WWTP could remove the FCB concentration by 3∼5 logs within the effluent of 104∼105 CFU/L, but the antibiotic resistant rate of FCB species increased significantly after WWTP. The dominant FCB changed from Escherichia coli in the influent (∼73.0%) to Klebsiella pneumoniae in the effluent (∼53.3%) after WWTP, where the Escherichia coli was removed the most, while Klebsiella pneumoniae was the most persistent. The secondary tank removed the most of FCB (by 3∼4 logs) compared to other processes, but increased all the concerned antibiotic resistant rate. The potential super bugs of FCB community showing resistance to all the target antibiotics were selected in the biological treatment unit of WWTP. The FCB showed the highest multiple antibiotic resistance (92.9%) in total which even increased to 100% in the effluent. Klebsiella has the highest antibiotic resistant rate in FCB, with a multiple antibiotic resistance rate of 98.4%. These indicated that the Klebsiella pneumoniae not just Escherichia coli should be specially emphasized after WWTP concerning the health risk associated with FCB community. [Display omitted] [ABSTRACT FROM AUTHOR]

• DOM (Dissolved Organic Matter) chemodiversity varied significantly from seasons. • Seasonal changes impact DOM composition and removal in WWTPs. • 78% of DOM compounds are lignin and 67% are CHO in the common formula. • Anaerobic unit in WWTP effectively removes fluorescent pollutants. • Microbial community structure explains 27.07% of DOM chemodiversity variation. The relationship between chemodiversity and microbial succession in wastewater treatment plants (WWTPs) is highly intricate and bidirectional. The specific contribution of the microbial community to changes in the composition of dissolved organic matter (DOM) within different biological treatment units remains unclear, as does the reciprocal influence of DOM composition on microbial succession. In this study, spectroscopy ((Excitation-emission matrix) EEM-PARAFAC, Ultraviolet (UV)-spectrum, Fourier transform infrared spectrometer (FT-IR)), Liquid chromatograph mass spectrometer (LC‒MS) and Fourier transform ion cyclotron resonance (FT-ICR) MS along with high-throughput sequencing technology were used to explore the relationship between chemodiversity and microbial succession in WWTPs concerning seasonal changes. The results showed that WWTPs with anaerobic/anoxic/oxic (A2O) processes can metabolize and transform most of the wastewater DOM, and the anaerobic unit has the highest removal rate for fluorescence DOM (FDOM, 14.07%-64.43%); the anaerobic unit increased aliphatic/proteins and lignin-like molecules but decreased relative intensity, while the anoxic unit removed unsaturated hydrocarbons, aromatic structures, and lignin-like substances. The impact of seasonal changes on the composition and removal of FDOM and DOM in wastewater treatment is significant, and the variations that occur during different seasons affect microbial activity, as well as the production, degradation, and transformation of organic compounds throughout the wastewater treatment process. Network analysis shows that Parcubacteria_genera_incertae_sedis plays a crucial role in DOM chemodiversity, highlighting the crucial contribution of microbial communities to both the structure and operation of the entire DOM network. The results in this study could provide some theoretical and practical basis for guiding the process optimization of WWTPs. [Display omitted] [ABSTRACT FROM AUTHOR]