International Journal of Environmental Science and Technology最新文献

Increasing pollutants in the environment becomes one of the major critical issues these days due to rapid urbanization and industrialization. Therefore, researchers pay attention towards photocatalytic composites (PC) for the degradation of pollutants. This present paper critically looks into the environmental impact of pollutants generation and the concepts behind the use of TiO₂ as well as doped TiO₂ in PC for the degradation of nitrogen dioxides (NOx), volatile organic agents and organic dye. The methods for evaluating degradation efficiencies of the above pollutants are clearly discussed in this paper. This review presents consensus knowledge of various influential parameters, such as, methods of preparation for making PC, type and amount of photocatalyst/raw materials and environmental conditions, etc., associated with the degradation of pollutants. Finally, recommendations are made for future studies in this review paper. This review provides a broader understanding of basic concepts and valuable insights for avenues of innovation in this field.

Graphical abstract

Water is essential resource vital for economic prosperity, well-being of ecosystems worldwide. Presence of arsenic, even in low concentrations, poses persistent threat due to its high toxicity, stability, its capacity to accumulate within food chains, affecting human health. To combat this issue, detection methods are striving to achieve lower limit of detection than World Health Organization standard of 10 parts per billion (133.3 nM), particularly focusing on toxic form, As³⁺. Various techniques have been developed to detect, quantify arsenic in drinking water, including spectroscopic and electrochemical methods. Spectroscopic methods offer high sensitivity and selectivity but can be complex, costly to operate, while electrochemical methods, although simpler, cost-effective, may sacrifice some sensitivity, selectivity. Recent years have witnessed emergence of portable, field-deployable arsenic sensing devices, primarily based on electrochemical or optical principles, with potential to transform arsenic contamination monitoring. This review explores recent advancements in arsenic detection techniques in drinking water, highlighting substantial progress in development of highly sensitive and selective methods. It covers range of sensor technologies, such as electrochemical sensors, optical sensors, and nanomaterial-based sensors, all of which offer improved detection limits, accuracy. It discusses integration of emerging technologies like machine learning and miniaturized devices for real-time arsenic monitoring in water sources. Practicality and cost-effectiveness of these techniques are evaluated, emphasizing need for robust, field-deployable sensors to ensure access to safe drinking water in both developed and developing regions. This review aims to contribute to ongoing efforts to mitigate the arsenic contamination crisis and protect public health.

Graphical abstract

In this work, a new biochar (BC) derived from woody forest residues and decorated with cobalt ferrite (BC/CoFe₂O₄) was synthesized via co-precipitation. This innovative approach entails a straightforward and cost-effective process. BC was produced via slow pyrolysis (1.66 °C min⁻¹ up to 450 °C, residence time: 72 h). The material was applied for the first time to remove direct red 80 dye (DR80). BC and BC/CoFe₂O₄ had moisture contents of 5.8% and 8.4%, ash of 24.1% and 30.0%, and volatile of 75.5% and 69.5%, respectively. These parameters are crucial for assessing BC quality. The H/C ratio was ~ 0.5, and the O/C ratio was ~ 0.2 for both materials. The materials exhibited thermal stability, with oxygenated groups. The pH_PZC of BC and BC/CoFe₂O₄ were 7.01 and 6.78, respectively. The ratios of D and G bands (I_D/I_G ratio) were 1.07 and 0.74 for BC and BC/CoFe₂O₄, respectively. BC presented peaks related to quartz, dolomite, and calcite, whereas BC/CoFe₂O₄ displayed peaks of CoFe₂O₄. BC presented a morphology of plate-shaped surface, while BC/CoFe₂O₄ presented irregular spheres of 6.6 ± 0.9 nm. The selected area diffraction pattern of BC/CoFe₂O₄ showed crystalline planes of CoFe₂O₄. The oxygen (74.97%), cobalt (8.86%), and iron (16.17%) were detected in BC/CoFe₂O₄ through Energy Dispersive Spectroscopy analysis, confirmed by Inductively Coupled Plasma Optical Emission Spectrometry. The BC/CoFe₂O₄ promoted practically 100% degradation of DR80 in 180 min. The species responsible for the degradation were identified as the photogenerated hole (h⁺) and O₂^•−. The material can be reused without a significant loss of efficiency.

Graphical Abstract

Carbon soot, traditionally considered a pollutant due to its harmful effects on human health and the environment, is now recognized as a valuable functional material. Carbon soot’s unique physical and chemical properties make it attractive for various applications, including energy storage, catalysis, electronics, water detoxification, and more. This review article covers the application of soot-derived carbon nanoparticles for water remediation. The article starts with discussing the soot formation mechanism, followed by a characterization of soot particles. Further, the application of carbon soot for oil–water separation and removal of contaminants from water are reviewed. The effect of various process parameters like pH, time of contact, and concentration are discussed. Further, the article discusses carbon soot particle’s limitations and future scope for water remediation. In conclusion, this review highlights the potential of carbon soot as a sustainable and cost-effective solution for water detoxification and presents an outlook for future research in this field. It also discusses the challenges and shortcomings of the work done till now in this area.

The ever-increasing growth of urban population in worldwide and their unsustainable use of land resources have turned resource planning and management into one of the world's most important environmental challenges. In recent years, the concept of "urban ecosystem health" has been developed to monitor the impacts of human activities on Earth's ecosystems. The present research aims to investigate the ecosystem health status of the Sanandaj city by introducing a spatial decision support system. Urban health indicators were extracted from the Pressure-State-Impact-Response framework and the health status of 26 districts of Sanandaj city has been investigated. Finally, by weighing and integrating of 16 indicators, the total health score in each urban district has been obtained. The results showed that the health status in 9.2% of the areas of Sanandaj were in a very poor to poor, in 30.8% in a poor to moderate, in 52% of the areas in a moderate to strong, and 7.9% of the areas were in a strong to very strong health status. It seems that most of the efforts to restore the health of Sanandaj ecosystem should be focused first on 3, 5, Nanleh and Garizeh and then, on 4, 6, 9, 10, 11, 12 and Naysar districts. The model introduced in this study can be used to monitor the health status of any urban ecosystem which is the most important factor in maintaining the stability and sustainability of urban ecosystems.

Wastewater containing organic pollutants has created serious environmental issues and severely threatened human health due to the industry’s rapid development. Fenton processes, among the most economical advanced oxidation methods, can efficiently decompose and completely mineralize organic pollutants. Fenton processes have been widely employed in wastewater treatment to remove organic dyes; however, their practical application is limited due to the secondary pollution of Fe sludge. This work used the electrospinning technique to create Fe-alginate/PVDF nanofibers with a mass ration of 1:0.3, followed by iron ion exchange (0.08 wt%) as a photo-Fenton catalyst. The catalytic degradation of 20 mg/L methylene blue revealed that Fe-alginate/PVDF nanofibers (10 mg) had remarkable photo-Fenton catalytic performance, degrading 97.24% of methylene blue within 40 min under optimized conditions (pH of 3, H₂O₂ concentration of 0.20 mM). Additionally, the wetting property and the development of the Fe-alginate coordination structure prevented iron leaching and strengthened the Fe-alginate/PVDF nanofibers’ structure stability, thus limiting secondary pollution of wastewater during application. Moreover, Fe-alginate/PVDF nanofibers could effectively remove MB over a wide pH range of 3.0–9.0, applied to the majority industrial wastewater (neutral or slightly acidic pH conditions). This work provides a facile strategy to prepare stable and cost-effective heterogeneous photo-Fenton catalysts, demonstrating potential applications in industrial-scale wastewater treatment.

The maritime transportation sector poses a significant environmental risk due to its reliance on fossil fuels and its proximity to coastal areas. To address this issue, the International Maritime Organization, authorized by the IPCC, is responsible for reducing and preventing ship-borne emissions. The International Maritime Organization regularly updates emission prevention measures through annual MEPC meetings, particularly under the MARPOL 73/78 Convention, to adapt to changing conditions. In this study, we utilized a bottom-up approach to calculate the emissions of NO_X, SO₂, CO, and PM₁₀ emitted by ships transiting through the Istanbul Bosphorus from 2014 to 2021. We employed the AERMOD air quality dispersion model to generate SO₂ spatial distribution maps, focusing on the year 2014 with the highest pollutant release. The obtained results were compared with measurements from air quality monitoring stations, allowing us to evaluate the contribution of maritime SO₂ emissions to overall Bosphorus pollution. Furthermore, we also examined the impact of low sulfur fuel usage after the sulphur was reduced from 3.5 to 0.5% by mass, in accordance with the regulations put into effect by IMO in 2020.

Healthcare facilities (HCFs) such as hospitals, clinics, and health centres are recognized as the first and last line of defence against unfavourable impacts of climate change. This study examined the climate resilience and environmental sustainability (CRES) of HCFs in seven pilot provinces of Iran. In this regard, the action levels of HCFs were explored in four major areas, including health workforce; water, sanitation and healthcare waste; energy; and infrastructure, technologies and products. Analysis of conditions at HCFs in the studied areas demonstrated that energy; infrastructure, technologies, products; and water, sanitation and healthcare waste are at a low level, while the health workforce area is considered as a medium level. Among the various types of HCFs the highest CRES is related to hospitals, and the lowest is allocated to rural–urban health centres. Therefore, raising the level of awareness, training and empowering health workforces, optimizing the use of resources particularly water and energy, waste minimization, replacing fossil fuels with renewable energy, and promoting new systems and technologies can improve HCFs resilience in these centres. The results of this research led to the establishment of an effective tool for the evaluation of the CRES of HCFs. In addition, identifying HCFs conditions can help policymakers and health system officials in planning and managing appropriately to increase the level of CRES of these systems.

This study aimed to investigate the impact of the ratio of Spirulina maxima biomass to inoculum on the anaerobic co-digestion of malting wastewater using upflow anaerobic sludge blanket pilot-scale reactors. The AD process occurred in mesophilic conditions, lasting for 369 h. The experimental conditions included three groups: (1) malting wastewater (control); (2) malting wastewater with an 80:20 inoculum/Spirulina maxima ratio; (3) malting wastewater with a 60:40 inoculum/Spirulina maxima ratio. The 60:40 inoculum/Spirulina maxima ratio demonstrated superior performance, generating 6.7 times more biomethane compared to both the control and the 80:20 inoculum/Spirulina maxima ratio. This condition achieved a chemical oxygen demand removal efficiency of 76%. Furthermore, the digestate generated did not exhibit phytotoxicity towards lettuce and barley. Therefore, co-digestion digestates can be effectively utilized in agriculture. Co-digestion was also found to be efficient in simultaneously treating co-digestion, generating biomethane, and producing biofertilizer. This work emphasizes a promising and sustainable approach to valorizing waste and effluents, which has positive impacts on bioenergy generation and food production. It promotes the principles of the circular economy and sustainability in agriculture.

The textile industry is reported as one of the most pollution-producing industries because of toxic colorants that are hard to remove by conventional treatment methods. These colorants have highly negative impacts on ecology and aquatic biota. Dye, which is a valuable resource, is discharged as waste in the effluent and is considered as an environmental threat, because of its low degradability. If this dye is recovered from wastewater, on the one side it can be reused and can give financial benefits, and on the other hand, its removal from the wastewater can be a secondary advantage for the environment as wastewater treatment could be simplified. Though various methods for the discoloration of textile effluent have been reported in the literature, but many of them are either expensive, inefficient, or environmentally unfriendly. The reported methods in the literature have different removal mechanisms which can be categorized as degrading mechanisms and non-degrading mechanisms. Though the removal of various dyes including indigo carmine is possible through both mechanisms, however for the recovery of these dyes from wastewater one should adopt a non-degrading mechanism. This article summarizes various reported dye removal methods and will relate the suitability of these methods and the extent to which they are suitable for dye recovery. Based on the nature of the treatment these methods are subclassified as physical, chemical, Physicochemical, biological, and physico-biological methods and this article will encapsulate the adaptivity, massiveness, and immensity of these methods for indigo dye removal and recovery. Upto 100% removal has been attained through various methods among which adsorption and filtration are the most feasible methods for recovery of Indigo dye from effluent.