Frontiers of Environmental Science & Engineering最新文献

Removing high-risk and persistent contaminants from water is challenging, because they typically exist at low concentrations in complex water matrices. Electrified flow-through technologies are viable to overcome the limitations induced by mass transport for efficient contaminant removal. Modifying the local environment of the flow-through electrodes offers opportunities to further improve the reaction kinetics and selectivity for achieving near-complete removal of these contaminants from water. Here, we present state-of-the-art local environment modification approaches that can be incorporated into electrified flow-through technologies to intensify water treatment. We first show methods of nanospace incorporation, local geometry adjustment, and microporous structure optimization that can induce spatial confinement, enhanced local electric field, and microperiodic vortex, respectively, for local environment modification. We then discuss why local environment modification can complement the flow-through electrodes for improving the reaction rate and selectivity. Finally, we outline appropriate scenarios of intensifying electrified flow-through technologies through local environment modification for fit-for-purpose water treatment applications.

The Beautiful China Initiative (BCI) is a vivid embodiment of the harmonious coexistence between humans and nature during modernization. Implementing the BCI is an effective method for achieving the goals of building a beautiful China, while offering a “Chinese solution” to global sustainable development. This article summarizes the progress and main experiences of the BCI, as well as analyzing the primary challenges facing its future development. Finally, five policy recommendations are proposed, which emphasize the importance of top-level design, coordinated planning, and a robust support system in the implementation of the BCI.

Photocatalysis has emerged a promising strategy to remedy the current energy and environmental crisis due to its ability to directly convert clean solar energy into chemical energy. Bismuth tungstate (Bi₂WO₆) has been shown to be an excellent visible light response, a well-defined perovskite crystal structure, and an abundance of oxygen atoms (providing efficient channels for photogenerated carrier transfer) due to their suitable band gap, effective electron migration and separation, making them ideal photocatalysts. It has been extensively applied as photocatalyst in aspects including pollutant removal, carbon dioxide reduction, solar hydrogen production, ammonia synthesis by nitrogen photocatalytic reduction, and cancer therapy. In this review, the fabrication and application of Bi₂WO₆ in photocatalysis were comprehensively discussed. The photocatalytic properties of Bi₂WO₆-based materials were significantly enhanced by carbon modification, the construction of heterojunctions, and the atom doping to improve the photogenerated carrier migration rate, the number of surface active sites, and the photoexcitation ability of the composites. In addition, the potential development directions and the existing challenges to improve the photocatalytic performance of Bi₂WO₆-based materials were discussed.

Carbon capture, utilization and storage (CCUS) technologies play an essential role in achieving Net Zero Emissions targets. Considering the lack of timely reviews on the recent advancements in promising CCUS technologies, it is crucial to provide a prompt review of the CCUS advances to understand the current research gaps pertained to its industrial application. To that end, this review first summarized the developmental history of CCUS technologies and the current large-scale demonstrations. Then, based on a visually bibliometric analysis, the carbon capture remains a hotspot in the CCUS development. Noting that the materials applied in the carbon capture process determines its performance. As a result, the state-of-the-art carbon capture materials and emerging capture technologies were comprehensively summarized and discussed. Gaps between state-of-art carbon capture process and its ideal counterpart are analyzed, and insights into the research needs such as material design, process optimization, environmental impact, and technical and economic assessments are provided.

Soil is a non-renewable resource, providing a majority of the world’s food and fiber while serving as a vital carbon reservoir. However, the health of soil faces global threats from human activities, particularly widespread contamination by industrial chemicals. Existing physical, chemical, and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process, as well as addressing the complexities of soil contamination on a regional scale. Viable solutions encompass monitoring and simulating soil processes, with a focus on utilizing big data to bridge micro-scale and macro-scale processes. Additionally, reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil, coupled with the high economic costs of remediation. Further, it is imperative to implement advanced remediation technologies, such as monitored natural attenuation, and embrace holistic soil management approaches that involve regulatory frameworks, soil health indicators, and soil safety monitoring platforms. Safeguarding the enduring health and resilience of soils necessitates a blend of interdisciplinary research, technological innovation, and collaborative initiatives.

There is a global need to reduce greenhouse gas emissions to limit the extent of climate change. A better understanding of how our own activities and lifestyle influence our energy use and carbon emissions can help us enable changes in activities that can lead to reductions in carbon emissions. Here we discuss an approach based on examining carbon emissions from the perspective of the unit C, where 1 C is the CO₂ from food a person would on average eat every day. This approach shows that total CO₂ emissions in China, normalized by the population, is 22.5 C while carbon emissions for a person in the US is 43.9 C. A better appreciation of our own energy use can be obtained by calculating carbon emissions from our own activities in units of C, for example for driving a car gasoline or electric vehicle a certain number of kilometers, using electricity for our homes, and eating different foods. With this information, we can see how our carbon emissions compare to national averages in different countries and make decisions that could lower our personal CO₂ emissions.

The World Health Organization has raised concerns about the possibility of airborne transmission in enclosed and poorly ventilated areas. Therefore, rapid monitoring of airborne viruses is necessary in multi-use facilities with dense population. Accordingly, an electrostatic air sampler (250 L/min) was developed in this work to obtain indoor viral aerosol samples for analysis via the Polymerase Chain Reaction (PCR). Aerosol tests with H1N1 and HCoV-229E were performed to evaluate the sample collection efficiency. PCR analysis, along with another aerosol test, was conducted to evaluate the recovery of the virus particles collected by the sampler. In laboratory tests, our electrostatic sampler obtained viral samples that were detectable by PCR under the simulated viral pandemic scenario (3000 RNA copies per cubic meter of air) within 40 min. The resulting cycle threshold (C_t) values were 35.07 and 37.1 for H1N1 and HCoV-229E, respectively. After the performance evaluation in the laboratory, field tests were conducted in a university classroom from October 28 to December 2, 2022. Influenza A and HCoV-229E were detected in two air samples, and the corresponding C_t values were 35.3 and 36.8. These PCR results are similar to those obtained from laboratory tests, considering the simulated viral pandemic scenario.

To avoid resource wastage and secondary environmental pollution, recycling and reusing waste wood powder is still a great challenge. Moreover, the poor viscosity and irregular pore size of wood powder limit its practical application. This study employed a green and convenient wood powder reconstitution strategy to achieve highly adhesive bonding and pore size control between wood powder particles, thus preparing a high-strength and super hydrophilic wood powder membrane. The wood powder fibers were partially dissolved and regenerated to create a reconstituted wood powder hydrogel membrane, using waste wood powder as the raw material. The wood powder reconstitution strategy offers advantages such as environmental friendliness, simplicity, cost-effectiveness, and strong universality. Furthermore, the materials exhibit excellent self-cleaning properties and superhydrophilicity. Driven by gravity, the membrane can purify oily wastewater and dyes. Additionally, the reconstitution strategy offers a new pathway for recycling wood powder.

The traits of rural domestic sewage emission are unclear, negatively affecting rural domestic sewage treatment and sewage management. This study used data from the Second National Pollution Source Census Bulletin to establish a data set. The spatial distribution characteristics and main factors influencing rural sewage discharge in the Northern Region were studied using spatial autocorrelation analysis and structural equations. The findings demonstrated that (1) a significant Spearman correlation between drainage water volume (DWV), chemical oxygen demand (COD), ammonia nitrogen (NH₃-N), total nitrogen (TN), and total phosphorus (TP) and that the correlation coefficients between DWV and COD, NH₃–N, TN and TP were 0.87**, 1.0**, 0.99**, 0.99**, respectively; (2) rural sewage discharge showed spatial autocorrelation, and rural domestic sewage discharge in the districts and counties with an administration was significantly higher than in the surrounding areas; and (3) social development was the main driver rural domestic sewage changes (path coefficient was 0.407**), and the main factors influencing rural domestic sewage discharge were the urbanization rate, years of education, and population age structure. This study obtained the spatial variation law and clarified the main influencing factors of rural domestic sewage to provide data support and a theoretical basis for subsequent rural sewage collection and treatment. Use of the Inner Mongolia Autonomous Region in northern China as a typical case, provides a theoretical foundation for scientific decision-making on rural domestic sewage treatment at the national and regional levels and offers new perspectives for managing pollutants.

Abstract

Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through inner-sphere coordination, strong competition for hydroxyl ions still hinders efficient water defluoridation. In addition, the critical issue of polysilicate scaling that results from the ubiquitous silicates must be addressed. To tackle these issues, an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Brønsted acidity is proposed. The feasibility of this approach is demonstrated by growing zirconium phosphate (ZrP) inside a gel-type anion exchanger, N201, to produce nanocomposite ZrP@N201, in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr⁴⁺ sites and Brønsted acidic monohydrogen phosphate groups (–O₃POH). Compared with the Lewis acidic nano-zirconium oxide analog (HZO@N201), ZrP@N201 exhibited a greatly improved adsorption capacity (117.9 vs. 52.3 mg/g-Zr) and mass transfer rate (3.56 × 10⁻⁶vs. 4.55 × 10⁻⁷ cm/s), while bulk ZrP produced a thermodynamically stable α-phase with Brønsted acidity that exhibited negligible adsorption capability toward fluoride. The enhanced defluoridation activity of ZrP@N201 is attributed to Brønsted acidity and the increased outer electron density of Zr⁴⁺ sites, as corroborated using XPS and solid-state NMR analysis. Moreover, Brønsted acidity strengthens the resistance of ZrP@N201 to silicate, allowing its full regeneration during cyclic defluoridation. Column tests demonstrated 3–10 times the amount of clean water from (waste) for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum oxide. This study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.