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Microbial fuel cell (MFC) coupled constructed wetland (CW) is regarded as a promising green technology due to its simultaneous removal performance for the co-occurrence of various contaminants in wastewater. In this study, the simultaneous removal performance of sulfamethazine (SMZ) and hexavalent chromium Cr(VI) in the CW and MFCCW systems was investigated. The removal efficiencies of total nitrogen (N), total phosphorus (P), and chemical oxygen demand (COD) were also examined. The results demonstrated that Cr(VI) was effectively eliminated with an excellent removal efficiency of >98.0 %, followed by SMZ with a removal efficiency of 70.3 %-85.6 %. Additionally, during the long-term operation period, the average removal efficiency for N, P, and COD ranged from 74.0 % to 96.1 %, 83.6 % to 94.1 %, and 91.1 % to 95.3 %, respectively. The microbial community and antibiotic resistance genes (ARGs) in the anode and cathode were also analyzed separately to evaluate the SMZ and Cr(VI) removal performance of MFCCW. The abundance of corresponding ARGs was slightly different in the anode and cathode regions. The average abundance of sul4 in the SMZ+Cr(VI) treatment MFCCW was significantly higher than that of other sul1-3. This study offers valuable insights for the simultaneous removal of SMZ and Cr(VI) from wastewater by MFCCW.

The occurrence of extreme weather events is becoming more frequent due to global climate change. A long-lasting dust outbreak in the spring of 2023 was triggered by Mongolia cyclones and cold fronts in the dust source areas. In this study, we illustrate the spatial distribution, the transport path of the dust and its influence on the air quality of downstream cities utilizing ground-based and space-borne measurements. Results indicate a more complicated pollution, coexisting of polluted dust stage S1 and pure dust stage S2. In S1, the aerosol was characterized by a dual-layer vertical structure-high extinction coefficient of nearly 1.0 km-1 with a low particle depolarized ratio (PDR) of 1300 µg/m3. PM10 positively correlated with trace gases in S1 while varying inversely with the pollution gases in S2. The results help to shed light on the classification of different types of dust and also be useful in developing an effective strategy to forecast air pollution in downstream areas.

Global warming caused by the emission of CO2 in industrial flue gas has attracted more and more attention. Therefore, to fix CO2 with high efficiency and environmentally friendly had become the hot research field. Compared with the traditional coal-fired power plant flue gas emission reduction technology, carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment, convenient operation and environmental protection. When the flue gas is treated by microalgae carbon fixation and emission reduction technology, microalgae cells can fix CO2 in the flue gas through photosynthesis, and simultaneously absorb NOx and SOx as nitrogen and sulfur sources required for growth. Meanwhile, they can also absorb mercury, selenium, arsenic, cadmium, lead and other heavy metal ions in the flue gas to obtain microalgae biomass. The obtained microalgae biomass can be further transformed into high value-added products, which has broad development prospects. This paper reviews the mechanisms and pathways of CO2 sequestration, the mechanism and impacts of microalgal emission reduction of flue gas pollutants, and the applications of carbon sequestration in industrial flue gas by microalgae. Finally, this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.

Coal power plants annually generate quantities of byproducts that release environmentally hazardous heavy metals like Cd and Pb. Understanding the behavior and spatiotemporal impacts on soils of these releases is crucial for pollution control. This study investigated the concentrations and isotope ratios of Cd/Pb in combustion byproducts, depositions and soils collected from a coal-fired power plant or its surrounding area. The pulverized fuel ash (PFA) and desulfurized gypsum (DG) exhibited heavier Cd isotopes with Δ114Cd values of 0.304‰ and 0.269‰, respectively, while bottom ash (BA) showed lighter Cd isotopes (Δ114CdBA-coal = -0.078‰), compared to feed coal. We proposed a two-stage condensation process that governs the distribution of Cd/Pb, including accumulation on PFA and DG within electrostatic precipitators and desulfurization unit, as well as condensation onto fine particles upon release from the stack. Emissions from combustion and large-scale transport make a significant contribution to deposition, while the dispersion of Cd/Pb in deposition is primarily influenced by the prevailing wind patterns. However, the distribution of Cd/Pb in soils not only exhibit predominant wind control but is also potentially influenced by the resuspension of long-term storage byproducts. The power plant significantly contributes to soil in the NW-N-NE directions, even at a considerable distance (66%-79%), demonstrating its pervasive impact on remote regions along these orientations. Additionally, based on the vertical behavior in the profile, we have identified that Cd tends to migrate downward through leaching, while variations in Pb respond to the historical progression of dust removal.

Phase change absorbents based on amine chemical absorption for CO2 capture exhibit energy-saving potential, but generally suffer from difficulties in CO2 regeneration. Alcohol, characterized as a protic reagent with a low dielectric constant, can provide free protons to the rich phase of the absorbent, thereby facilitating CO2 regeneration. In this investigation, N-aminoethylpiperazine (AEP)/sulfolane/H2O was employed as the liquid-liquid phase change absorbent, with alcohol serving as the regulator. First, appropriate ion pair models were constructed to simulate the solvent effect of the CO2 products in different alcohol solutions. The results demonstrated that these ion pair products reached the maximum solvation-free energy (ΔEsolvation) in the rich phase containing ethanol (EtOH). Desorption experiment results validated that the inclusion of EtOH led to a maximum regeneration rate of 0.00763 mol/min, thus confirming EtOH's suitability as the preferred regulator. Quantum chemical calculations and 13C NMR characterization were performed, revealing that the addition of EtOH resulted in the partial conversion of AEP-carbamate (AEPCOO-) into a new product known as ethyl carbonate (C2H5OCOO-), which enhanced the regeneration reactivity. In addition, the decomposition paths of different CO2 products were simulated visually, and every reaction's activation energy (ΔEact) was calculated. Remarkably, the ΔEact for the decomposition of C2H5OCOO- (9.465 kJ/mol) was lower than that of the AEPCOO- (26.163 kJ/mol), implying that CO2 was more likely to be released. Finally, the regeneration energy consumption of the alcohol-regulated absorbent was estimated to be only 1.92 GJ/ton CO2, which had excellent energy-saving potential.

In the quest for effective solutions to address Environ. Pollut. and meet the escalating energy demands, heterojunction photocatalysts have emerged as a captivating and versatile technology. These photocatalysts have garnered significant interest due to their wide-ranging applications, including wastewater treatment, air purification, CO2 capture, and hydrogen generation via water splitting. This technique harnesses the power of semiconductors, which are activated under light illumination, providing the necessary energy for catalytic reactions. With visible light constituting a substantial portion (46%) of the solar spectrum, the development of visible-light-driven semiconductors has become imperative. Heterojunction photocatalysts offer a promising strategy to overcome the limitations associated with activating semiconductors under visible light. In this comprehensive review, we present the recent advancements in the field of photocatalytic degradation of contaminants across diverse media, as well as the remarkable progress made in renewable energy production. Moreover, we delve into the crucial role played by various operating parameters in influencing the photocatalytic performance of heterojunction systems. Finally, we address emerging challenges and propose novel perspectives to provide valuable insights for future advancements in this dynamic research domain. By unraveling the potential of heterojunction photocatalysts, this review contributes to the broader understanding of their applications and paves the way for exciting avenues of exploration and innovation.

Global warming and nitrogen (N) deposition have a profound impact on greenhouse gas (GHG) fluxes and consequently, they also affect climate change. However, the global combined effects of warming and N addition on GHG fluxes remain to be fully understood. To address this knowledge gap, a global meta-analysis of 197 datasets was performed to assess the response of GHG fluxes to warming and N addition and their interactions under various climate and experimental conditions. The results indicate that warming significantly increased CO2 emissions, while N addition and the combined warming and N addition treatments had no impact on CO2 emissions. Moreover, both warming and N addition and their interactions exhibited positive effects on N2O emissions. Under the combined warming and N addition treatments, warming was observed to exert a positive main effect on CO2 emissions, while N addition had a positive main effect on N2O emissions. The interactive effects of warming and N addition exhibited antagonistic effects on CO2, N2O, and CH4 emissions, with CH4 uptake dominated by additive effects. Furthermore, we identified biome and climate factors as the two treatments. These findings indicate that both warming and N addition substantially impact soil GHG fluxes and highlight the urgent need to investigate the influence of the combination of warming and N addition on terrestrial carbon and N cycling under ongoing global change.

Lake ecosystems are extremely sensitive to nitrogen growth, which leads to water quality degradation and ecosystem health decline. Nitrogen depositions, as one of the main sources of nitrogen in water, are expected to change under future climate change scenarios. However, it remains not clear how nitrogen deposition to lakes respond to future meteorological conditions. In this study, a source-oriented version of Community Multiscale Air Quality (CMAQ) Model was used to estimate nitrogen deposition to 263 lakes in 2013 and under three RCP scenarios (4.5, 6.0 and 8.5) in 2046. Annual total deposition of 58.2 Gg nitrogen was predicted for all lakes, with 23.3 Gg N by wet deposition and 34.9 Gg N by dry deposition. Nitrate and ammonium in aerosol phase are the major forms of wet deposition, while NH3 and HNO3 in gas phase are the major forms of dry deposition. Agriculture emissions contribute to 57% of wet deposition and 44% of dry deposition. Under future meteorological conditions, wet deposition is predicted to increase by 5.5% to 16.4%, while dry deposition would decrease by 0.3% to 13.0%. Changes in wind speed, temperature, relative humidity (RH), and precipitation rates are correlated with dry and wet deposition changes. The predicted changes in deposition to lakes driven by meteorological changes can lead to significant changes in aquatic chemistry and ecosystem functions. Apart from future emission scenarios, different climate scenarios should be considered in future ecosystem health evaluation in response to nitrogen deposition.

Microbial fuel cells (MFCs) face significant challenges related to low power output, which severely limits their practical applications. Coupling MFC with other technologies and stacking MFCs are feasible solutions to enhance power output. In recent years, the coupling and stacking technology of MFCs has become a research hotspot in the field of environmental energy. This paper first outlines the basic configurations of MFCs and then analyzes the advantages and disadvantages of different setups in the context of coupling and stacking. Subsequently, it discusses in detail the coupling systems of MFC with other technologies, as well as several configurations of stacked MFCs and the phenomenon of voltage reversal. Based on these investigations, the paper proposes future research directions aimed at optimizing MFC performance, thereby enhancing their potential for energy recovery from wastewater and supporting the commercialization and scaling of MFC technology.

As global climate change problems become increasingly serious, the world urgently needs to take practical measures to deal with this environmental issue. In this sense, China's carbon peaking and carbon neutrality goals endowed an ingenious solution. Various industries in China have actively responded to this policy call, and various enterprises have started to carry out the work of carbon emission reduction, especially in water supply industry. In order to reduce carbon emission, we must first calculate carbon emissions and understand the level of carbon emission. At present, the carbon emissions accounting of water supply industry is mostly carried out on the partial work of some individual units within the enterprise, and there is no accounting case for the whole process of water supply work. This work innovatively proposes a method to calculate the carbon emissions generated in the whole water supply procedure. The carbon emission in the whole water supply procedure originates from the leakage of water supply network and the maintenance of water supply network, and all the carbon emissions involved in these two aspects are calculated. Moreover, the key points of carbon emission reduction are analyzed according to the accounting results, and a potential carbon emission reduction scheme is proposed. The research can provide a reference for the overall carbon emission accounting strategies and the construction of carbon emission reduction plans in the future.