International Journal of Environmental Science and Technology最新文献

A family of anthropogenic organic pollutants with a long history of use, per- and polyfluoroalkyl substances (PFAS) are present in a wide range of environmental compartments, including drinking water, soil, biota, surface water, and groundwater. As a result of their persistent nature in the environment, PFAS have been found in several species of wildlife worldwide, such as invertebrates, aquatic organisms, amphibian species, aquatic plants, alligator, seabird, mammal tissues, as well as in human body. This review provides an in-depth assessment of the distribution of commonly detected PFAS in surface water within five distinct regions of the United States. Furthermore, the research aims to identify the key sources that contribute to the presence of PFAS and pinpoint data gaps in specific states, emphasizing the need for further research. The Southeastern region, particularly the states of Florida, South Carolina, North Carolina, and Virginia, has been observed to show a higher degree of PFAS contamination. The states of California, Colorado, Nevada, and Montana in the Western region, as well as Maryland, New Jersey, New York, and New Hampshire in the Northeast region also showed a higher presence of PFAS. In the Southwest region, we identified a significant lack of data, while in the Midwest, with the exception of Michigan, we observed a comparatively lower amount of PFAS in surface water. It is expected that including more PFAS in addition to the few commonly studied will increase the total concentration of PFAS, which aids in understanding the actual degree of PFAS pollution. The synthesis of fluoropolymers and the incorporation of PFAS in the manufacturing and production of consumer goods, together with the utilization of fluorinated AFFF, have been recognized as notable sources of PFAS. Possible strategies to decrease and eliminate PFAS from the US are discussed as well.

Chemical pretreatment enhances the digestibility of resistant materials, but its effect on complex substrates like sesame wastes rich in lignocellulose and lipids requires validation. This study compared the impact of oxidant, acid, and alkali pretreatments on physicochemical properties and thermophilic degradative enzyme activity during composting. Correlations between thermophilic enzymes and physicochemical factors were analysed to investigate the effects of different pretreatments on lignocellulose and lipid-rich composting. Acid and oxidant pretreatments improved composting efficacy by increasing peak temperature, extending the thermophilic stage, and reducing moisture content. Acid pretreatment accelerated lignocellulose degradation by promoting endo-cellulase and xylanase activity and prevented total nitrogen loss through creating an acidic environment with low protease activity. Alkali pretreatment enhanced lipase activity and lipid degradation, while it also increased protease activity and total nitrogen loss. Correlation analysis indicated temperature and moisture content were the main positive and negative factors affecting degradative enzyme activities, respectively. Despite the merits of each pretreatment, acid pretreatment was most effective for sesame wastes and manure composting. These findings advance the development of efficient composting strategies for recalcitrant agricultural wastes.

Phosphorus is a non-renewable resource and essential for humanity. Due to its discharge in treated and untreated sewage, it became an aquatic pollutant, leading to eutrophication. Exploring the potential approach for phosphate recovery species, such as biochar, is indispensable to ensure food and water security. Therefore, this study investigates the synergic effects of heating rate (5 °C min⁻¹, 10 °C min⁻¹, and 15 °C min⁻¹), temperature (350 °C, 450 °C, and 550 °C) and residence time (0, 30, and 60 min) using a Box–Behnken experimental design in the production of a sawdust calcium-biochar and how the factors affect the phosphate removal. The phosphate removal ranged from 7.6 to 93%, with eleven products above 70%. All the independent variables were statistically significant, highlighting temperature, in linear and quadratic terms. The regression significance and lack of fit tests indicated that the model was applicable to the observed data, with total R² of 97% and adjusted R² of 92%, indicating that the model was suitable to evaluate the percentage of phosphate removal. The results were confirmed by the characterization techniques, such as BET, moisture, volatile matter, ash content and FT–IR, where pore size and functional groups on the surface of the biochar explained the influence of the variables. And the XRD characterization showed the calcium species in the biochar surface. Thus, using a Box–Behnken design allied to the response surface methodology allows to explore the biochar as a promising alternative for phosphate recovery for the first time in literature.

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The sorption of zinc chloride ions from hydrochloric acid-based solutions using anionic resins was investigated. A two-stage experiment was planned. In the first stage, parameter optimization was performed using the Taguchi experimental optimization approach for type of anionic resins, initial Zn (II) ion concentration, resin dose, agitation rate, and temperature and time of the process as process parameters. According to the signal—to—noise ratio values calculated with the larger better-quality feature; the optimum parameter levels were determined as chloride form resin, 10 g/L, 1200 mg/L, 200 rpm and 35 °C and 90 min, respectively. Under optimum operating conditions, the sorption capacity of the resin for zinc chloride complex ions was 46.52 mg/g. The energy dispersive X-Ray analyses confirmed that zinc chloride complexes bind to the resin’s surfaces. In the second step, equilibrium and kinetic tests were performed under the optimum parameters. The tests results were compared with six equilibrium isotherm models with 2 or more parameters and four kinetic models. The non-linear solution approach was applied for all models. Langmuir isotherm and the general order models were the best fit. The values of ({K}_{L}) and ({q}_{m,L}) for the Langmuir model were 2.15*10^–3 L/g and 66.08 mg/g, respectively. The kinetic model can be given by an equation of order 3.26. Accordingly, ({k}_{n}) and ({q}_{e,n}) were 2.18*10^–5 min/(g mg)^2.26 and 60.03 mg/g, respectively. The process mechanism was a typical chemical sorption. According to the results of desorption tests conducted using 1 M HCl, the desorption efficiency was 65%.

Municipal sludge aerobic compost application in land faces limitations due to the potential hazard of heavy metals, and adding heavy metal passivator proved a pathway to relieve this issue. However, as a heavy metal passivator, sodium lignosulfonate hasn't been applied in municipal sludge aerobic compost. In this paper, we selected sodium lignosulfonate and proportionally added it to municipal sludge aerobic compost for 45 days to evaluate the passivation impact of Cr, Zn, Pb and Cu. The results showed that sodium lignosulfonate can improve the stability of heavy metals by reducing the bioavailable forms. Specifically, adding 5% sodium lignosulfonate showed the best passivation effect of heavy metals with passivation rates of Cr, Zn, Pb and Cu at 81.46%, 32.58%, 98.61% and 30.91%, respectively. What’s more, scanning electron microscope energy dispersive system, Fourier transforms infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray powder diffraction revealed that sodium lignosulfonate promoted the passivation of heavy metals by enhancing the degradation of organic matter and forming new insoluble sulfates and phosphates. This study might contribute to the understanding of the mechanism of heavy metal passivation during aerobic composting.

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Plastic waste, considered a great threat to the environment, requires an effective treatment process. The ability of the microbes to oxidize the polymeric chain (C–C bonds), hydrolyze and produce carbon dioxide and water as final products of degradation was studied. The process becomes complicated due to structural complexity of the polymer. The present study is the continuation of the LDPE degradation using the Winogradsky Column. The determination of metabolites formed on degradation is discussed. The FTIR analysis indicated the reduction in the intensity of the C-H, confirming the cleavage of the alkane chains in LDPE. The metabolites produced during the degradation resulted in the formation of smaller alkanes, which contain C32, C22, C16, C18 and aromatic compounds such as phenols and benzene dicarboxylic acid. The occurrence of terminal oxidation of the polymeric chain, cleavage, fragmentation and cyclization of the alkanes confirm the biodegradation process. The current research also focuses on the biodegradation of LDPE using bacterial strains isolated from dumpsite soil samples. The degraded LDPE was analyzed for its metabolite production using GC–MS. It enabled us to understand and hypothesize an overview pathway of LDPE degradation by bacterial strains. The hypothesized pathway indicated that bacterial strains performed fragmentation and cyclization of the long polymeric chain, followed by hydrogenation and oxidation, resulting in the formation of alcohols, aldehydes, ketones and carboxylic acid compounds leading to ester formation. The esters are then understood to enter the ꞵ-oxidation pathway or TCA cycle, producing carbon dioxide and water molecules.

In the process of rapid urbanization, any unexpected event will harm the stability of the city. Strengthening urban resilience construction will effectively respond to unexpected events. Taking 22 counties (cities, districts) in Ningxia, Northwest China as the research object, 20 indicators are selected from four aspects of economic, social, infrastructure, and ecological resilience to construct an urban resilience evaluation index system. The entropy-TOPSIS model (consisting of the Entropy method and the Technique for Order Preference by Similarity to an Ideal Solution method) is used to comprehensively evaluate the resilience and comprehensive resilience of various dimensions of county-level cities. The results show that: (1) There is a significant spatial differentiation in the economic, social, infrastructure, and ecological resilience of county-level cities in Ningxia, resulting in a higher comprehensive resilience of cities in the northern region compared to those in the southern region, and comparatively high and high resilience is distributed in the central districts and counties of the northern and southern regions. (2) Low, comparatively low, medium, comparatively high, and high resilience cities account for 13.64%, 31.82%, 31.82%, 18.18% and 4.54% of the total number of county-level cities in Ningxia, respectively. Among them, Xingqing District has the highest comprehensive resilience and Jingyuan County has the lowest comprehensive resilience. The research findings can provide a basis for the dynamic assessment of resilience in county-level cities in Ningxia, the analysis of the impact of geological environment changes on urban resilience, and thus a theoretical and practical basis for the sustainable development of county-level cities in Ningxia and the enhancement of their ability to respond to emergencies.

Iran plans to build the first coal-fired power plant in 2025 as part of its electricity generation development program. Coal-fired power plants are the main anthropogenic source of mercury emissions. According to Article 8 of the Minamata Convention on Mercury, all Parties need to set targets to control mercury emissions from these sources. No studies have been carried out to estimate mercury emissions from future development plans for coal-fired power plants in Iran. Therefore, the main objectives of this research are to estimate mercury emissions from this power plant and evaluate the best available technologies to control mercury emissions. In the first step, to achieve these objectives, mercury emissions under 13 scenarios were estimated based on the interactive process optimization guidance model and experimental data. To predict ground-level mercury concentrations in the second step, a Gaussian atmosphere dispersion model coupled with a mesoscale numerical weather prediction model was applied. Finally, the hazard quotient was used to assess inhalation risks. The results show that hourly mercury emissions, mercury concentration, and mercury emission factor are estimated to be 0.672 g/h, 0.2 μg/Nm³, and 0.45 kg/TWh, respectively, when circulating fluidized bed boilers equipped with the in-furnace desulfurization process and the cold-side electrostatic precipitator unit are utilized as the best available technology for mercury emission control. In conclusion, the hazard quotient indicates that ground-level mercury concentrations are improbable to induce inhalation risks for the community living within a 30 km radius from this power plant.

Nowadays, wastewater treatment is a huge challenge, especially with the increasing of human caused pollution. The recent study introduced new adsorbents based on thermal treatment of wastewater sludge to eliminate hexavalent chromium from wastewater. The new adsorbents were characterized by different chemical and physical tools, such as sludge pH, total solids, elemental concentration, FTIR, TGA, SEM, XRD, and PET surface area. The adsorption efficiency of sludge samples toward Cr (VI) from aqueous media was studied using the batch method. Various parameters, such as solution initial concentration, pH, time, and adsorbent dose, have been studied. The sludge samples showed high efficiency for Cr (VI) adsorption in aqueous media, with removal efficiency reaching 98.4%, 75%, and 98.4% for SI, SII, and SIII, respectively. The Cr (VI) adsorption occurred via electrostatic attraction in acidic medium. The adsorption data is well-fitting to pseudo-second order and Elovich kinetics models as well as the Freundlich isotherm, which reflect the Cr (VI) favorability adsorption on the hetero-energetic active sites of sludge samples. Additionally, a field investigation of the thermcally treated sludge adsorbent (SIII) application on real wastewater samples from Egyptian wastewater treatment plants and drainage revealed the high removal efficiency of over 67% for TSS, 80% for BOD, 75% for COD, and 100% for Cr (IV), Ni (II), and Fe (II).

Waste management has emerged as a critical issue in the wake of the COVID-19 pandemic and the earthquake that struck southeast Turkey on February 6th, 2023, particularly regarding the disposal of face masks and gloves. Extensively utilized for disease prevention and maintaining personal hygiene, these items are categorized as medical waste, presenting significant disposal challenges in Turkey. This study aims to overcome these challenges by prioritizing key factors in waste management during the COVID-19 era through the application of the Spherical Fuzzy Analytic Hierarchy Process (SF-AHP) in Istanbul. By conducting a comprehensive literature review and consulting with experts, relevant criteria for managing this medical waste have been identified and prioritized. Furthermore, a sensitivity analysis of the decision support model is performed to evaluate its robustness. The data highlight the crucial importance of recycling, landfilling, and incineration capacities, regulatory frameworks, and incineration costs as primary determinants and criteria shaping the waste management landscape. The sensitivity analysis highlights the resilience of our proposed methodology, demonstrating consistent and robust prioritization outcomes even with varying criteria weights, thereby validating the reliability of the methodology in informing policy decisions. The originality of this study lies in its innovative application of spherical fuzzy sets—offering high accuracy and compatibility with human reasoning—to the management of face masks and gloves waste, an area not previously explored using Spherical Fuzzy Multi-Criteria Decision Making (SF-MCDM) in current literature. This novel approach introduces a rigorous and pioneering methodology for investigating this specific aspect of waste management and enriches the academic conversation by providing a practical SF-MCDM framework.