Water, Air, & Soil Pollution最新文献

The dyeing industry wastewater has greatly hampered the ecological environment. The carbon quantum dots (CQDs) is a promising catalyst for photocatalytic degradation. To control the specified structure of CQDs, a designable-green deep eutectic solvents (DESs) was targeted as the precursor. In this work, a copper-doped solid-state Cu-CQDs was successfully prepared by combustion method from glycerol/choline chloride/CuCl₂·2H₂O DESs, and characterized by Fourier transform infrared spectroscopy, XRD, XPS, UV–Vis spectroscopy, and fluorescence spectroscopy. The analysis revealed that the metallic copper-doped Cu-CQDs have better morphological and structural properties and exhibit good optics characteristics. The prepared CQDs were applied to the photocatalytic degradation of Rhodamine-B (RhB). It was found that the ⋅O₂⁻ was the main active specie, and it can efficient degrade RhB up to 95%.

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Air pollution is a substantial threat to both human health and plant life. While there has been plenty of study on the effects of air pollution on human health in Dhaka, the influence on plants in this urban environment has yet to be investigated. This study investigated the heavy metal content (Pb, Cd, Cr, Cu, Ni, Zn, Fe, and Mn) in various plant species to elucidate the effects of air pollution on vegetation. Samples of soil and corresponding plant leaves from Mangifera indica (Mango tree), Swietenia mahagoni (Mahogany tree), Polyalthia longifolia (Ashoka tree), Ficus religiosa (Fig tree), and Artocarpus heterophyllus (Jackfruit tree) were collected from industrial, traffic, and control location in Dhaka city. Concentrations of heavy metals in both soil and leaves were analyzed, and the geoaccumulation index, contamination factor, and transfer coefficient were calculated to assess the correlation between metal concentration and air pollution impact. At traffic locations, lead (Pb) and zinc (Zn) concentrations ranged from 2605 to 4289 mg/kg and 35 to 1157 mg/kg, respectively. In industrial areas, chromium (Cr) and copper (Cu) concentrations varied from 386 to 954 mg/kg and 27 to 458 mg/kg, surpassing World Health Organization recommended limits. Pb and Cr exhibited the highest geo-accumulation index. Traffic sites demonstrated the highest Pb transfer coefficients across plant species. This study is very significant as it provides important understandings for urban planning and environmental management, highlighting the adverse effects of pollution on plant species in Dhaka.

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In line with the objective of Sustainable Development Goals (SDGs) 3, 6, 11, 12, and 15, a water footprint assessment (WFA) was conducted at the International Islamic University Malaysia (IIUM) Campus in Malaysia. This study illustrates the concept of water footprint (WF) to map and quantify water consumption and water pollution incurred inside IIUM. Based on calculations conducted on blue water footprint (WFblue), approximately 279,810 m³/month was consumed in June 2022. Zone 5 was found to consume more clean water at 212,440 m³/month compared to other zones in the study area, due to its size and population. In terms of grey water footprint (WFgrey) for the water body calculated, it was found that sampling point P4 has 6,475,770 m³/month of WFgrey resulting from the accumulation WFgrey at three sampling points which are inlets to sampling point P4. This value is found to be higher than WFgrey produced by the community of IIUM at 1,947,495 m³/month. For WFgrey domestic, it showed that Zone 5 produced the highest WFgrey at 88,476,290 m³/month which also included the value of Total Suspended Solid (TSS), Biochemical Oxygen Demand (BOD₅), and Ammonia Nitrate (NH₃⁻N) at the Sewerage Treatment Plants (STPs). Results from this study confirmed that the amount of discharged polluted water is higher than the consumption of clean water. The water scarcity of blue water (WSblue) calculation showed that the value at each zone did not exceed 1.0 and can be categorized as sustainable. Nevertheless, the findings from the water pollution level (WPL) analysis showed all zones did not exceed 1.0 except Zone 5, whose WPL value nearly reached 1.0. Therefore, it can be concluded that all the Zones located in IIUM are still considered sustainable. The management of IIUM is recommended to take mitigation actions to ensure continuous sustainability of the campus, especially at Zone 5.

The synthesis of a covalent triazine framework polymer (CTF-P) from the polymerization of piperazine and cyanuric chloride is reported in this study. The prepared CTF-P was used as photocatalyst to evaluate its activity for the degradation of ofloxacin (OFL), an emerging concern in water. The material was characterized using N₂ isotherms, XRD, FTIR, TEM, SEM, EDX and DRS-UV–Vis analyses. FESEM and TEM images confirmed that CTF-P exhibits a nanosheet-like structure. The findings showed that 98.6% of OFL would degrade under pseudo-first-order kinetics in 120 min of exposure to 50 W LED light. Quenching tests showed that holes, superoxide, and exited electrons play crucial roles in the degradation of OFL. The recyclable nature of CTF-P was demonstrated over five cycles, maintaining an impressive 88.9% removal efficiency, which showcases the feasibility of the proposed photocatalyst for reuse. The strategic design of photocatalysts based on the CTF framework offers a novel approach to enhancing the degradation of organic pollutants.

Over the past few decades, numerous researchers have focused on creating novel, practical, affordable, and easy-to-use techniques for determining and estimating organic pollutants in aquatic environments. This study aims to determine ADP drug using KMnO₄ as reagent by spectrofluorometric method. At pH 4, the fluorescence spectrum of the produced complex ion association [Mn (II)-ADP] was obtained at 420 nm with high intensity. The quantification and detection limits were 0.56 and 0.18 µg mL⁻¹, respectively. The Stern–Volmer and the apparent binding constant were calculated to be 158.6 and 159.95 L mol⁻¹, respectively. Also, different variables were investigated such as KMnO₄ concentration, and the optimized conditions were pH 4, and 0.1 µg mL⁻¹, respectively. In studied samples, adapalene recovery percentages ranged from (90–95%), and (90–93%) in wastewater, and sea water, respectively. These results represent an exceptional and a perfect recovery percentage.

In this present study, initially, activated carbon is derived from eucalyptus wood utilizing a single-stage activation method. Then, the developed sample is characterized by different characterization and analytical techniques such as (i) proximate analysis, (ii) ultimate analysis, (iii) Brunauer–Emmett–Teller (BET) surface area analysis, (iv) Barrett-Joyner-Halenda (BJH) pore size analysis, (v) Scanning Electron Microscopy (SEM) surface morphology analysis, (vi) Fourier transform infrared spectroscopy (FTIR) surface chemistry analysis, and (vii) Thermogravimetric Analysis (TGA) thermal stability analysis to evaluate its surface features and ensure suitability as an adsorbent for carbon capture. After that, the characterized adsorbent is filled inside the capture unit and coupled to a test engine. This study uses a computerized diesel engine, and the test engine is operated by employing two distinct test fuels: (i) petro-diesel (D100) and (ii) 80% Jatropha methyl ester (JME) + 20% D100 (JME20). The adsorbent performance is examined in terms of CO₂ adsorption, and the adsorbent sample’s adsorption parameter is discussed. The results obtained from experimental findings are compared with the adsorbent performance and fuels used in a test engine. The experimental test results showed that about 44% and 38% of CO₂ emissions are captured for D100 and JME20 fuel operations, respectively.

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In this study, polyethyleneimine-mesoporous silica composite materials were prepared and the effectiveness of the promising sorbents in adsorbing CO₂ was evaluated, along with the impacts of the silica support types (Mesoporous Silica Nanoparticles (MSN) and Mobil Composition of Matter No.48 (MCM-48)), polyethyleneimine (PEI) loading percentages (50 and 70 wt.%), calcination, surface functionalization by alkyl chains (CTMABr), and adsorption temperature (75 and 100 °C). The analysis’s results revealed that the pores of the sorbents were mostly covered with PEI molecules following PEI-functionalization, and the specific surface area and pore volume were also reduced with rising amine content. The highest CO₂ adsorption capacities were achieved for UC-MCM-48–50 and UC-MSN–50 at 2.26 mmol/g and 3.31 mmol/g, respectively. The CO₂ uptake capacities of CC-MSN–50 and CC-MCM-48–50, composed by dispersing CTMABr surfactant with the calcined materials before incorporating PEI, were remarkably similar to those of non-surfactant functionalized adsorbents. When the temperature’s influence on CO₂ adsorption capacity was evaluated, the maximum holding capability adsorbent UC-MSN–50 had a slight increase in adsorption capacity (~ 3.6%), whereas UC-MCM-48–50 had a considerable drop (~ 23.9%) as the temperature elevated to 100 °C. Besides, Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherms were used to model pure CO₂ adsorption data, and a thermodynamic study was applied. In conclusion, a low-cost and more beneficial approach, which included less PEI handling and eliminating the calcination step, was implemented to enhance the CO₂ sorption capacity of composites of PEI with the long alkyl chain template MCM-48 or MSN silica support materials.

Coal mining is a critical economic for Colombia. However, mineral extraction is usually carried out near rivers that provide ecosystem services to riverside populations. Cesar River receives discharges from several open-pit coal mines, as well as from other anthropogenic sources. The aim of this work was to assess the chemical and the toxicity profile of the sediments from this river. Bottom sediment samples were collected from 12 points along the river, including tributaries and a Ramsar site, the Zapatosa Marsh. Trace elements were quantified employing ICP-MS, and mercury (Hg) was measured using a direct Hg analyzer. Aqueous extracts (K-medium) were obtained from dried sediments (1:3 ratio) and tested using Caenorhabditis elegans, assessing mortality, locomotion and growth as end points. Transcriptional effects associated with various toxicity mechanisms were evaluated using GFP-related transgenic strains (mtl-2, sod-4 and gst-1). Some trace metals enriched along the course of the river, especially Hg and V. Sediment extract-induced lethality was low (1.5–6.4%); however, nematode growth and locomotion decreased downstream the river, showing inhibition rates up to 23.3 and 35.4%, respectively. Extracts from downstream points increased the mRNA expression of tested genes compared to that elicited by the most upstream site, with greater values on stations receiving domestic sewage and mining outputs. Cobalt and lead were positively associated with metallothioneins and gst-1 expression. In short, coal mining areas should be closely monitored for trace-element release and their impact on biota. The Colombian government should implement laws and programs to protect key ecosystems from mining activities, as a commitment to sustainable development goals.

Air pollution is widespread and poses significant health risks, including respiratory and cardiovascular diseases, cancer, and even lead to death. Among the strategies to mitigate exhaust gases, biological treatment technology has gained significant attention due to its high treatment efficiency, cost-effectiveness, and environmental friendliness. This technology has become a key area of research. This paper discusses the principles, scope, advantages, and cons of various biological treatment methods, including biofiltration, biotrickling filtration, bioscrubbing, and membrane bioreactors. Noteworthy advantages of current biological treatment for exhaust gases include cost savings, reduced energy consumption, and lower secondary pollution risks. However, limitations exist, such as the treatment of treating low concentration and high flow rate of exhaust gases, and the dependence on specific microbial species and fillers. Combining biological treatments with other technologies could significantly improve effectiveness. The review also explores challenges and future directions, aiming to enhance the application of biological treatments in exhaust gas management towards sustainable development.

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This study investigates aerobic landfill stabilization using three bioreactors with different operational modes: R1 with oxygenated (~ 90% pure oxygen) leachate recirculation and waste mass aeration, R2 with conventional leachate recirculation (without oxygenation) and waste mass aeration, and R3 as an anaerobic control. The waste stabilization was assessed by reductions in COD, ammonia nitrogen, NOx (nitrate and nitrite nitrogen), and total phosphorus removal, as well as reductions in volatile solids and subsidence of waste height. Among the three reactors, R1 exhibited the best performance, with ~ 85% COD removal efficiency likely due to the high DO content during leachate recirculation. Additionally, R1 achieved ~ 99% removal efficiency of ammonia nitrogen through rapid aerobic nitrification. An exponential attenuation model was applied to describe the degradation of organic substances, with degradation rates of COD and NH₃-N increasing from 0.005 and 0.007 d⁻¹ to 0.01 and 0.021 d⁻¹, respectively, when leachate recirculation and oxygenation were applied. Reactor R1 could meet the COD emission limit of 150 mg/L, as specified by WHO surface water regulations, by day 478, while reactors R2 and R3 are expected to achieve this level by days 567 and 742, respectively. The results indicated that the aerobic conditions in R1, supplemented with pure oxygen (~ 90%) aeration, elicited rapid stabilization of the simulated landfill waste, reflected by a high waste settlement of ~ 63.5%. The findings suggest that this strategy can improve landfill stabilization in practice, optimize landfill space reuse, and enhance MSW management by reducing the load on existing leachate treatment facilities.