Leaching of per- and polyfluoroalkyl substances (PFAS) from food contact materials with implications for waste disposal.

Leaching of per- and polyfluoroalkyl substances (PFAS) during the post-consumer disposal of food contact materials (FCMs) poses a potential environmental threat but has seldom been evaluated. This study characterized the leaching behavior of PFAS and unidentified precursors from six common FCMs and assessed the impact of environmental conditions on PFAS release during disposal. The total concentration of 21 PFAS ranged from 3.

Can on-site leachate treatment facilities effectively address the issue of perfluoroalkyl acids (PFAAs) in leachate?

In recent decades, the presence of perfluoroalkyl acids (PFAAs) in municipal solid waste leachate has emerged as a growing concern. Research has focused on PFAA release and occurrence characteristics in landfill and waste-to-energy leachate, highlighting their significant impact when released into wastewater treatment plants. Given the extremely high loading rate faced by current on-site leachate treatment plants (LTPs), the objective of this study is to assess whether the current "anaerobic/aerobic (A/O) + membrane bioreactor (MBR) + nanofiltration (NF) + reverse osmosis (RO)" configuration is effective in PFAAs removal.

Separation of Chloride and Sulfate Ions from Desulfurization Wastewater Using Monovalent Anions Selective Electrodialysis.

The high concentration of chloride ions in desulphurization wastewater is the primary limiting factor for its reusability. Monovalent anion selective electrodialysis (S-ED) enables the selective removal of chloride ions, thereby facilitating the reuse of desulfurization wastewater. In this study, different concentrations of NaCl and NaSO were used to simulate different softened desulfurization wastewater.

Four-decades evolutionary development of municipal solid waste management in China: Implications for sustainable waste management and circular economy.

This study collected data on waste generation and management in China between 1979 and 2020 from government statistics and literature and reviewed the development of municipal solid waste (MSW) management in China. The extended stochastic impact by regression on population, affluence and technology (STIRPAT) model was employed to identify the driving forces of MSW generation, and the cointegration analysis showed that economy (0.35,  = -3.

The Adsorption Behaviors and Mechanisms of Humic Substances by Thermally Oxidized Graphitic Carbon Nitride.

Thermal oxidation is efficient for enhancing the photocatalysis performance of graphitic carbon nitride (g-CN), while its effect on adsorption performance has not been fully studied, which is crucial to the application of g-CN as adsorbents and photocatalysts. In this study, thermal oxidation was used to prepare sheet-like g-CN (TCN), and its application for adsorption of humic acids (HA) and fulvic acids (FA) was evaluated. The results showed that thermal oxidation clearly affected the properties of TCN.

Identification of key surfactant in municipal solid waste leachate foaming and its influence mechanism.

Serious foaming problems and the excessive consumption of defoamer have undoubtedly become one of the most critical problems that hinder municipal solid waste (MSW) leachate treatment efficiency and industry development. Since there is limited research penetrating the foaming mechanism and identification of the key surfactants, current defoaming and surfactant removal techniques lack pertinence and orientation. In this study, a foaming characterization device was developed and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) was optimized to accurately identify the key surfactants affecting leachate foaming and offer a glimpse into their interaction mechanisms.

Occurrence and removal of per- and polyfluoroalkyl substances (PFAS) in leachates from incineration plants: A full-scale study.

Municipal solid wastes (MSWs) contain diverse per- and polyfluoroalkyl substances (PFAS), and these substances may leach into leachates, resulting in potential threats to the environment and human health. In this study, leachates from incineration plants with on-site treatment systems were measured for 17 PFAS species, including 13 perfluorocarboxylic acids (PFCAs) and 4 perfluorosulfonic acids (PFSAs). PFAS were detected in all of the raw leachates and finished effluents in concentrations ranging from 7228 to 16,565 ng L and 43 to 184 ng L, respectively, with a greater contribution from the short-chain PFAS and PFCAs.

Reduction capacity of humic acid and its association with the evolution of redox structures during composting.

The reducing capacity (RC) of compost-derived humic acid (HA) is related to the type and number of redox-active functional moieties in its structure and has a considerable environmental influence on its geochemical redox cycle. Composting treatment can affect the redox-active fractions of organic substances through microbial transformation and degradation. However, the relationship between the RC of compost-derived HA and its fluorescence component and infrared spectra remains unclear.

Treatment of wastewater using black soldier fly larvae, under different degrees of biodegradability and oxidation of organic content.

The biological treatment process based on the metabolism of Black Soldier Fly (BSF) larvae proved to be a highly promising technique for the treatment of high organic content (HOC) wastewater, such as sewage from food industries, leachate from municipal solid waste (MSW) landfill, etc. The present study was aimed at achieving a better understanding of how biodegradability and degree of oxidation of organic content might influence treatment performance and biomass quality. Six leachates characterised by similar COD (Chemical Oxygen Demand) but different BOD/COD (Biochemical Oxygen demand/COD) and TOC/COD (Total Organic Carbon/COD) ratios were tested.

Occurrence of per- and polyfluoroalkyl substances (PFAS) in municipal solid waste landfill leachates from western China.

Landfill leachate has been documented as a significant source of trace organic pollutants, comprising an expansive family of per- and polyfluoroalkyl substances (PFAS). This study presents the findings on the distribution of 13 perfluoroalkyl carboxylates (PFCAs) and 4 perfluoroalkyl sulfonates (PFSAs) in leachates from 6 municipal solid waste (MSW) landfills in western China. The total concentrations of 17 PFAS in sampled leachates ranged from 1805 to 43,310 ng/L, and 15 compounds were detected in all samples.

Preparation of artificial MSW leachate for treatment studies: Testing on black soldier fly larvae process.

When approaching the study of new processes for leachate treatment, each influencing variable should be kept under control to better comprehend the treatment process. However, leachate quality is difficult to control as it varies dramatically from one landfill to another, and in line with landfill ageing. To overcome this problem, the present study investigated the option of preparing a reliable artificial leachate in terms of quality consistency and representativeness in simulating the composition of real municipal solid waste (MSW) leachate, in view of further investigate the recent treatment process using black soldier fly (BSF) larvae.

Enhanced adsorption of humic/fulvic acids onto urea-derived graphitic carbon nitride.

Since humic substances (HSs) can cause environmental problems, their elimination has been attracting more and more concerns. In this study, we investigated HSs adsorption onto urea-derived graphitic carbon nitride (CNU) and elucidated adsorption mechanisms (i.e.

Life Cycle Assessment of Leachate Treatment Strategies.

Increasingly stringent regulations for leachate discharge call for leachate treatment plants (LTPs) to increase their treatment capacity by adopting membrane treatment processes to remove nitrogen and organics beyond conventional biological treatment processes. This study developed four common treatment strategies based on the existing operation and construction conditions of seven representative LTPs in China. We evaluated the LTPs' environmental impacts using life cycle assessment (LCA) following the International Organization for Standardization (ISO 14040 and ISO 14044).

Insights into Adsorption of Humic Substances on Graphitic Carbon Nitride.

Graphitic carbon nitride (CN) has been widely used in environmental pollution remediation. However, the adsorption of organic compounds on CNs, which has practical significance for the environmental application of CNs, is poorly understood. For the first time, this study systematically investigated the adsorption behaviors and mechanisms of humic substances (HSs), i.

Enhanced darkening effect from the interaction of MnO and oxygen on the component evolution of amino-phenolic humic-like substances.

Humification is greatly enhanced by metallic oxides in nature, and the related products are critical to various environmental processes. However, little is known about the interaction between metallic oxides and oxygen in promoting the oxidative polymerization of small organic molecules during the humification process. The synthesis of humic-like acids (HLAs) with MnO was performed in the presence and absence of oxygen, and the influence of oxygen and MnO on the composition evolution of amino-phenolic HLAs was illustrated.

Calcium leaching characteristics in landfill leachate collection systems from bottom ash of municipal solid waste incineration.

Calcium leaching is a critical factor in the clogging of leachate collection systems (LCS), a phenomenon that affects landfill stability and operation. The bottom ash (BA) of municipal solid waste (MSW) incineration plants contains large quantities of calcium-based compounds. Landfilling is the main disposal method for BA in China that intensifies the consequences of LCS clogging.

Effect of submerged combustion evaporation on Cd complexation potential of organic matter in municipal solid waste landfill leachate.

Despite the strong ability for complexation of heavy metals, a high amount of humic substances (HS) is always contained in membrane retentate from municipal solid waste landfill leachates treatment processes. Submerged Combustion Evaporation (SCE) can be used to effectively concentrate the membrane retentate. However, the impact of the SCE treatment on HS complexation capacity is still unclear.

Insights into Mechanism of Hypochlorite-Induced Functionalization of Polymers toward Separating BFR-Containing Components from Microplastics.

Surface functionalization of polymers is significant for an emerging flotation technique for separation of microplastics toward the recycling of plastic wastes. In this study, the hypochlorite-induced functionalization of polymers, including ABS, PMMA, PS, and PVC polymers, was intensively investigated. Afterward, its emerging application in flotation separation of microplastic mixtures was assessed based on a Box-Behnken design of the response surface methodology.

Population dynamics of microbial species under high and low ammonia nitrogen in the alternate layer bioreactor landfill (ALBL) approach.

Anaerobic landfill process is still believed to be a complex ecosystem due to the lack of knowledge on the functional activities of microbial species. This research sought to introduce a novel landfill bioreactor, named here as the alternate layer bioreactor landfill (ALBL) of fresh MSW (FW) and stabilized waste (CT) to avoid inhibitory conditions for the microbial species in anaerobic landfill. The stabilized waste layer in the bottom of landfill cell significantly changed microbial ecology of fresh MSW which in turn reduced the concentrations of NH-N (29-31%) and VFAs (33-38%) in the ALBL approach, compared to fresh MSW disposal in sanitary landfill.

Optimizing green ferrate (VI) modification towards flotation separation of waste polyvinylchloride and acrylonitrile-butadiene-styrene mixtures.

The recycling of waste plastics is of considerable significance with environmental and economic benefits, while available separation approaches have been considered as a major bottleneck for its widespread application. Thus, we proposed a simple method, flotation along with surface modification, to separate waste acrylonitrile-butadienestyrene and polyvinylchloride mixtures. Single-factor experiment was conducted to determine the critical parameters in surface modification.

Optimization of Surface Treatment Using Sodium Hypochlorite Facilitates Coseparation of ABS and PC from WEEE Plastics by Flotation.

Waste acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) as dominant components in waste electrical and electronic equipment (WEEE) plastics show significant potential for recycling, which is severely restricted by efficient separation method. We proposed a novel surface treatment method using sodium hypochlorite for facilitating coseparation of ABS and PC from WEEE plastics by flotation for recycling. Optimization of surface treatment process was performed with response surface methodology using Box-Behnken design.

Mechanism of oxidation and catalysis of organic matter abiotic humification in the presence of MnO.

Humification plays a critical role in the environmental fate of organic wastes, and MnO holds great promise for enhancing this reaction. However, the effects of MnO on the enhancement of the humification reaction remain ambiguous. To better reveal the mechanism by which MnO enhances the reaction and investigate the fate of the humification products, abiotic humification experiments were performed using increasing concentrations of dissolved organic matter (DOM) to a fixed amount of MnO.

Adsorption removal of refractory organic matter in bio-treated municipal solid waste landfill leachate by anion exchange resins.

Refractory organic matters (ROM) are the dominant organic matters in the membrane bioreactor -treated MSW landfill leachate, which are usually resistant to microbial degradation. Advanced membrane systems, which are expensive and generally for drinking water treatment, have to be used to make the final effluent meet discharge requirements. Anion exchange approach might be another option to remove ROM from leachate.