Environments最新文献

{"title":"Development of a Hydrometallurgical Process for the Extraction of Cobalt, Manganese, and Nickel from Acid Mine Drainage Treatment By-Product","authors":"Alejandro Agudelo Mira, Qingqing Huang","doi":"10.3390/environments11090194","DOIUrl":"https://doi.org/10.3390/environments11090194","url":null,"abstract":"Critical minerals (CMs) are pivotal in modern industries, such as telecommunications, defense, medicine, and aerospace, contributing significantly to regional and global economic growth. However, the reliance on external sources for 26 out of 50 identified CMs raises concerns about supply chain vulnerabilities. To address this, the research focused on developing a hydrometallurgical process for extracting cobalt, manganese, and nickel from acid mine drainage (AMD) treatment by-products, emphasizing the need to diversify CM supply chains within the United States (US). A solution composed of an REE solvent extraction raffinate loaded with cobalt, manganese, nickel, and various impurity metals was utilized as a feedstock in this study. The developed hydrometallurgical process involved initial sodium hydroxide precipitation to remove impurities like aluminum and iron from an SX raffinate solution generated during the extraction of rare earth elements (REEs). Precipitation stages were performed in a pH region ranging from 2 to 12 to identify the optimum pH values, achieving a tradeoff between recovery and impurity removal. A subsequent precipitation process at pH 5–10 yielded a product rich in CMs, such as manganese, cobalt, and nickel. Further separation steps involved nitric acid washing, resulting in a Mn product with a purity of 47.9% by weight and a solution with extractable concentrations of cobalt and nickel. Stagewise precipitation with sodium sulfide subsequently produced three solid products: cobalt and nickel product at pH 1–5, manganese product at pH 5–10, and magnesium at pH 10–12. The study also explored other separation approaches, including solvent extraction, to enhance the separation of nickel from cobalt. Overall, the developed hydrometallurgical process generated the following products with varying degrees of purities: cobalt (9.92 wt.%), nickel (14 wt.%), manganese (47.9 wt.%), and magnesium (27.49 wt.%). This research aimed to contribute to the sustainable extraction of CMs from secondary sources, reducing the US’ reliance on imports and promoting a more resilient supply chain for these crucial elements.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological Shifts: Plant Establishment in an Animal-Based Ecosystem","authors":"Linda J. Walters, Paul E. Sacks, Katherine Harris, Giovanna McClenachan","doi":"10.3390/environments11090193","DOIUrl":"https://doi.org/10.3390/environments11090193","url":null,"abstract":"Shifts from saltmarsh to mangroves are well-documented at mangrove poleward boundaries. A regime shift from intertidal oyster (Crassostrea virginica) reefs to mangrove islands has recently been documented in transitional phases in Florida, USA. To understand the local drivers of an oyster/mangrove regime shift and potential tipping points leading to a permanent mangrove state, we tracked all mangrove propagules (n = 1681) across 15 intertidal oyster reefs with or without adult mangroves for 15 months in Mosquito Lagoon, FL. While no propagule bottleneck was observed, few (3.2%) mangrove propagules/seedlings survived on reefs with no prior encroachment, compared to 11.3% and 16.1% on reefs with established older (pre-1943) or newer (1943 to present) adult mangrove stands, respectively. In total, 90.6% of the arriving propagules were from the red mangrove Rhizophora mangle; 13.2% of these were alive at the end of this study. Survival was <1% for black (Avicenna germinans) and 0% for white (Laguncularia racemosa) mangroves. Factors that promoted red mangrove success included close proximity (≤0.3 m) to adult mangroves, especially black mangroves; partial, upright burial of propagules in sediment; and arrival on reefs after annual high-water season. Additionally, once reefs had 50% mangrove cover, the density of red mangrove seedlings increased from 0.04 to 0.46 individuals m−2. Although climate change has alleviated the impact of extreme freezes on mangroves, local factors determine whether the regime shift will be complete and permanent; positive feedback loops associated with established mangroves suggest mangrove recruitment on intertidal oyster reefs will continue to increase.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innovative Pavement Materials: Utilizing Corn Stover and Fly Ash in Geopolymers","authors":"Anu Paneru, Viral Sagar, Mohammad Tarikuzzaman, Joan G. Lynam, Stephen T. Gordon, Shaurav Alam","doi":"10.3390/environments11090192","DOIUrl":"https://doi.org/10.3390/environments11090192","url":null,"abstract":"The development of each nation is evaluated by its infrastructure, and each nation is competing with the others in infrastructure advancement, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are concrete and asphalt, which pose significant environmental challenges. This research gives insight into the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. This study examines the impact of three FA and CS mixture percentages and the particle size of CS on the compressive strength and porosity of geopolymer. The results indicate that incorporating larger amounts of CS in fly ash-based geopolymer may decrease the compressive strength of the geopolymer. Smaller CS particle sizes also tend to lead to lower compressive strength. Porosity of the geopolymer tended to increase with the incorporation of higher percentages of CS, particularly for smaller corn stover sizes. As a fine aggregate replacement for geopolymer, CS incorporation has the potential to reduce mined aggregate obtained from a process that harms the environment.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Management of Wadden Sea Salt Marshes in the Context of Nature Conservation, Coastal Flooding and Erosion Risks: A Review","authors":"Angela Eden, Frank Thorenz","doi":"10.3390/environments11090191","DOIUrl":"https://doi.org/10.3390/environments11090191","url":null,"abstract":"Salt marshes in the southern North Sea are part of the UNESCO World Heritage Site, Wadden Sea, the largest unbroken system of intertidal sand and mud flats in the world. They provide a very high nature value while significantly contributing to coastal flood and erosion risk management as a nature-based element of flood and erosion risk management systems for densely populated coastal areas. Climate change-induced sea-level rise is a significant concern: an integrated approach to salt marsh management adapted to the effects of climate change necessitates an understanding of the impact of different management strategies. This review commences with a description of the biogeomorphological conditions and processes in salt marshes for a better understanding of the natural dynamics and how they are influenced by management and climate change. Next, the impact of salt marshes on hydrodynamic processes and their role as nature-based elements of flood and erosion risk management is presented; management options and implementation methods are discussed and analysed concerning coastal flood management and nature conservation requirements. In conclusion, targeted salt marsh management needs to consider the initial conditions and the development aims of the specific site are integrated into a conceptual framework. Salt marshes have the potential to adapt to sea-level rise, thereby contributing to the long-term protection of coastal areas.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Air Pollution and Climate Change: A Pilot Study to Investigate Citizens’ Perception","authors":"Ilaria Stanisci, Giuseppe Sarno, Olivia Curzio, Sara Maio, Anna Antonietta Angino, Patrizia Silvi, Liliana Cori, Giovanni Viegi, Sandra Baldacci","doi":"10.3390/environments11090190","DOIUrl":"https://doi.org/10.3390/environments11090190","url":null,"abstract":"Air pollution and climate change are risk factors for noncommunicable diseases of paramount importance and of major concern in a population. Their complex interaction suggests the need for an integrated and participatory approach by health professionals and citizens. During the Italian BRIGHT-NIGHT (European Researchers’ Night) at the Pisa Research Campus of National Research Council (CNR), a laboratory focusing on environmental epidemiology issues and open to the public was set up. A self-administered questionnaire was distributed, with the aim of investigating the individual perception, knowledge, opinions and attitudes in relation to 12 different environmental, natural and anthropogenic hazards. The questionnaire was completed by 44 subjects aged over 18 years (47.6% female, 56.8% university graduates, 61.4% employed). Air pollution and climate change were considered two priorities for environmental protection and public health by 72.1%, prompting about one third of the subjects to commit to increasing active commuting. The results of this pilot survey indicate a diffuse awareness of air pollution and climate change as main environmental determinants to be tackled in order to protect public health.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low Concentrations of Biochar Improve Germination and Seedling Development in the Threatened Arable Weed Centaurea cyanus","authors":"Riccardo Fedeli, Tiberio Fiaschi, Leopoldo de Simone, Claudia Angiolini, Simona Maccherini, Stefano Loppi, Emanuele Fanfarillo","doi":"10.3390/environments11090189","DOIUrl":"https://doi.org/10.3390/environments11090189","url":null,"abstract":"In the context of sustainable agriculture, the search for soil improvers that boost crop growth without harming biodiversity is gaining much attention. Biochar, the solid residue resulting from the pyrolysis of organic material, has recently emerged as a promising bioproduct in enhancing crop yield, but there is a lack of information regarding its effects on arable biodiversity. Thus, in this study, we tested the effect of biochar application on the germination and seedling growth of cornflower (Centaurea cyanus L., Asteraceae), a threatened arable weed, under laboratory conditions. We investigated various parameters, including germination percentage (GP%), mean germination time (MGT), germination rate index (GRI), germination energy (GE%), fresh and dry weight (mg) of seedlings, and radicle length (mm) under biochar treatments at different concentrations: 0% (control), 0.1%, 0.2%, 0.5%, 1%, and 2%. Our findings revealed a significant increase in GP, GE, and GRI at biochar concentrations of 0.5% and 1%. MGT slightly increased at 0.1% biochar. Seedling fresh weight was unaffected by biochar application, whereas seedling dry weight exhibited a significant increase at 0.5% biochar. Radicle length showed a substantial increase under 0.1% biochar on day one, and was significantly higher at 0.2% and 1% biochar on day two. However, by day three, no more statistically significant differences in radicle length were observed between biochar-treated diaspores and controls (i.e., biochar had positive effects only in the first stages). These results suggest that the application of biochar at intermediate concentrations (0.5% and 1%) overall provides the most benefit to the germination and seedling growth of C. cyanus.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of PFAS Exposure on Neurodevelopment: A Comprehensive Literature Review","authors":"Seth D. Currie, Jia-Sheng Wang, Lili Tang","doi":"10.3390/environments11090188","DOIUrl":"https://doi.org/10.3390/environments11090188","url":null,"abstract":"Neurodevelopmental disorders (NDDs) encompass a range of conditions that begin during the developmental stage and cause deficits that lead to disruptions in normal functioning. One class of chemicals that is of increasing concern for neurodevelopmental disorders is made up of per- and polyfluoroalkyl substances (PFAS). In this comprehensive literature review, we investigated data from epidemiological studies to understand the connection between PFAS exposure and neurodevelopmental endpoints such as cognitive function, intelligence (IQ), and memory, along with behavioral changes like Attention-Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorders (ASD). When we reviewed the findings from individual studies that analyzed PFAS levels in biological samples and their association with NDD, we concluded that there was a correlation between PFAS and neurodevelopmental disorders. The findings suggest that children exposed to higher PFAS levels could potentially have an increased risk of ASD and ADHD along with an inhibitory effect on IQ. While the results vary from one study to another, there is increasing association between PFAS exposure and neurodevelopmental disorders. Importantly, the findings provide valuable insights into the adverse effects associated with PFAS exposure and neurodevelopment.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"675 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancements on Ultrasonic Degradation of Per- and Polyfluoroalkyl Substances (PFAS): Toward Hybrid Approaches","authors":"Olalekan Simon Awoyemi, Ravi Naidu, Cheng Fang","doi":"10.3390/environments11090187","DOIUrl":"https://doi.org/10.3390/environments11090187","url":null,"abstract":"Per- and polyfluoroalkyl substance (PFAS) contamination has emerged as a significant environmental concern, necessitating the development of effective degradation technologies. Among these technologies, ultrasonication has gained increasing attention. However, there is still limited knowledge of its scale-up or on-site applications due to the complexity of real-world conditions and its high energy consumption. Herein, we provide an overview of recent advancements in the ultrasonic degradation of PFAS toward hybrid technologies. This review contains information regarding the physical and chemical properties of PFAS, followed by an exploration of degradation challenges, the mechanisms of ultrasonication, and recent experimental findings in this field. The key factor affecting ultrasonication is cavitation intensity, which depends on ultrasonic frequency, power density, and PFAS structure. Its main advantages include the generation of reactive species without chemicals and the compatibility with other degradation technologies, while its main disadvantages are high energy consumption and limited applications to liquid-based media. We also highlight the integration of ultrasonication with other advanced oxidation processes (AOPs) to create hybrid systems for enhanced degradation of PFAS in order to significantly improve PFAS degradation efficiency, with enhancement factors ranging between 2 and 12. Finally, we discuss prospects for scaling up the ultrasonic degradation of PFAS and address the associated limitations. This review aims to deepen the understanding of ultrasonication technology in addressing PFAS contamination and to guide future research and development efforts.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using Indoor and Outdoor Measurements to Understand Building Protectiveness against Wildfire, Atmospheric Inversion, and Firework PM2.5 Pollution Events","authors":"Daniel L. Mendoza, Tabitha M. Benney, Erik T. Crosman, Ryan Bares, Derek V. Mallia, Cheryl S. Pirozzi, Andrew L. Freeman, Sarah Boll","doi":"10.3390/environments11090186","DOIUrl":"https://doi.org/10.3390/environments11090186","url":null,"abstract":"The world has seen an increase in the frequency and severity of elevated outdoor pollution events exacerbated by the rise in distant polluting events (i.e., wildfires). We examined the intersection between indoor and outdoor air quality in an urban area using research-grade sensors to explore PM2.5 infiltration across a variety of pollution events by testing two separate indoor environments within the same building. We confirmed prior work suggesting that indoor environments in buildings are most protective during wintertime inversion events and less so during fireworks and wildfire events. The building indoor environment protectiveness varies notably during different pollution episodes, especially those that have traveled longer distances (e.g., wildfires), and we found evidence of varied infiltration rates across PM2.5 types. Inversion events have the lowest infiltration rates (13–22%), followed by fireworks (53–58%), and wildfires have the highest infiltration rates (62–70%), with distant wildfire events persisting longer and, therefore, infiltrating for greater durations than local-wildfire-related particle matter. The differences in PM infiltration rates were likely due to the combined effects of several factors, including varying particle size, concentration, and chemistry. Subsequently, the local wildfires had different temporal air quality impacts than distant wildfire pollution in this case. Based on these findings, indoor air quality appears more conducive to protective action and policies than outdoor air quality because the built environment may serve to shield individuals from outdoor air.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Analysis of Suspected Microplastics in the Muscle and Gastrointestinal Tissues of Fish from Sarasota Bay, FL: Exposure and Implications for Apex Predators and Seafood Consumers","authors":"Eric Conger, Miranda Dziobak, Elizabeth J. Berens McCabe, Tita Curtin, Ayushi Gaur, Randall S. Wells, John E. Weinstein, Leslie B. Hart","doi":"10.3390/environments11090185","DOIUrl":"https://doi.org/10.3390/environments11090185","url":null,"abstract":"Microplastics have been found in the gastrointestinal (GI) fluid of bottlenose dolphins (Tursiops truncatus), inhabiting Sarasota Bay, FL, suggesting exposure by ingestion, possibly via contaminated fish. To better understand the potential for trophic transfer, muscle and GI tissues from 11 species of dolphin prey fish collected from Sarasota Bay were screened for microplastics (particles < 5 mm diameter). Suspected microplastics were found in 82% of muscle samples (n = 89), and 97% of GI samples (n = 86). Particle abundance and shapes varied by species (p < 0.05) and foraging habit (omnivore vs. carnivore, p < 0.05). Pinfish (Lagodon rhomboides) had the highest particle abundance for both tissue types (muscle: 0.38 particles/g; GI: 15.20 particles/g), which has implications for dolphins as they are a common prey item. Findings from this study support research demonstrating the ubiquity of estuarine plastic contamination and underscore the risks of ingestion exposure for wildlife and potentially seafood consumers.","PeriodicalId":11886,"journal":{"name":"Environments","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}