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Purification of Heavy Metals Contaminated Groundwater by Electro-Coagulation Process Using Graphite Electrodes
2024
Muhibbu-Din, Eniola Ismail | Jimoh, Heekmah Oiza | Kehinde, David Pelumi | Tinuoye, Ifeoluwa Agnes
The application of the electro-coagulation process to the identified contaminated groundwater at Abala community, a suburb of Ilorin metropolis in Kwara state, Nigeria, is the subject of this study. The groundwater samples were electro-coagulated in a batch reactor of 2.5L containing 1 litre volume of contaminated groundwater for 1 hour per run using a DC power supply ranging from 10v to 20v at constant current 5amp and 2amp to 6amp at constant voltage 10v using graphite electrodes. The results revealed that electro-coagulation process can reduce turbidity, TDS, Electrical Conductivity, BOD, TOC, COD, and color by 97.3 %, 91.2 %, 91.1 %, 96 %, 99.7%, 99.7%, 79.9%, and 82.96 %, respectively. Through Atomic Absorption spectroscopy analytical study, the process also shows removal efficiency of Manganese, Iron, and Zinc of 82.96 percent, 70.0 percent, and 95.30 percent, respectively. The outcome of the electro-coagulation process met the World Health Organization (WHO), the United States Environmental Protection Agency (USEPA), and the Water Environment Partnership In Asia (WEPA) criteria for both drinking water and general industrial wastewater discharge guidelines. The electro-coagulation treatment for contaminated groundwater was efficient and effective, therefore it is recommended in this study for Nigerians.
Mostrar más [+] Menos [-]Various Elements Levels in Four Freshwater Mussels Shells Obtained from Gölbaşı Lake, Turkey
2024
Uğurlu, Erkan | Kumruoğlu, Levent Cenk
The aim of this study was to determine by SEM-EDS analysis of the surface morphologies of the periostracum and nacreous layer and to determine the sodium (Na), Strontium (Sr), manganese (Mn), potassium (K), titanium (Ti), iron (Fe), magnesium (Mg), cobalt (Co), copper (Cu), chromium (Cr), zinc (Zn) and nickel (Ni) metals levels in the shells of the mussel (Potomida semirugata, Unio terminalis, Anodonta pseudodopsis and Leguminaia wheatleyi) obtained from Gölbaşı Lake, Turkey. The results of the study, the representative SEM analysis and corresponding EDS spectra of the periostracum and nacreous layer of the shells of freshwater mussels confirmed the presence of elemental compositions, including CaCO3. P. semirugata and U. terminalis have the aragonite prismatic layer that shows typical polygonal organizing, regular and polygonal crystal forms, with hexagonal and coexisting rhombic shapes. However, while A. pseudodopsis has round aragonite crystals (Rc), L. wheatleyi has irregular crystal plate layers (Irc). CaCO3, detected strong Ca peaks as well as C and O peaks with Mg and Si peaks. On the other hand, sodium (Na) was found in the highest concentrations ranging from 82.30±0.040 to 155.37±0.050 μg/g, and its concentrations were also higher than those of other metals in all species. The most abundant elements in shells of four freshwater mussel’s species were Sr, Na, and Mn which ranged from 26.07±0.44-58.023±0.52 μg/g, 82.30±0.040-155.37±0.050 μg/g, and 6.06±0.044-9.66±0.053 μg/g respectively. To our knowledge, this is the first study in Turkey that is researched the different four freshwater mussel species in the Gölbaşı Lake, Turkey.
Mostrar más [+] Menos [-]Assessing Heavy Metal Contamination In Surface Water And Sediments Of The Tafna River (North-West Of Algeria)
2024
Mechouet, Ouezna | Foudil Bouras, AliEddine | Benaissa, Noureddine | Ait Hamadouche, Yasmine | Haddad, Fatima Zohra | Dimache, Alexandru
Water and sediments have become a major threat. Heavy metals, some of which are potentially toxic, are distributed in different areas by different routes. Tafna river was studied upstream and downstream under contrasting hydrological conditions during the year 2020.The different levels and sources of pollution are assessed by combining geochemical indicators: geoaccumulation index (GI-go), contamination factor (CF), pollutant loading index (PLI) and supplemented by correlation matrix (CM) as statiscal analyses added principal component analysis (PCA). The elements analysed were physical and chemical parameters (pH, DO, electrical conductivity CE and, COD BOD5), and the metallic elements (Fe, Cd, Pb, Cu, Mn and Zn). They were classified based on how contaminated they were: for the water compartment (Fe> Mn>Cu>Pb>Cd>Zn), while for sediments (Zn> Pb>Fe>Cd>Cu >Mn). The results suggest that the chemical composition of the waters of the Tafna river is influenced by the lithology, which contributes to the enrichment of the sediments. All of the indicators suggest an average levels of sediment and water pollution at the Tafna's summit, then decreases towards the bottom due to the geomorphology with multiple sources of pollution. As a result, our study offers the first comprehensive information on the amount of heavy metals present in the riverbed's sediment and water.
Mostrar más [+] Menos [-]A Novel Nanocomposite Cellulose Acetate Membrane using Green Synthesized Silver Nanoparticles for Bioremediation of Leachate
2024
Pakhuongte, Paul Lalremruot | Velrajan, Mahalakshmi
Conventional remediation techniques have become outdated and insufficient to treat the influx of pollution from different fronts (air, water, and soil). Green synthesis of nanoparticles is an eco-friendly approach to remediate these contaminants and Membrane technology is increasingly becoming popular for the treatment of wastewater due to their efficiency and versatility against a wide array of contaminants. Cellulose acetate (CA) is a polymer obtained from cellulose and hence considered biodegradable, making it a more environmentally friendly option over other conventional polymers. In this present study, silver nanoparticles were synthesized using Staphylococcus aureus and characterized by UV-vis Spectrometer, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Analysis (EDAX). The synthesized green silver nanoparticles were assimilated onto synthesized CA membrane films to fabricate nanocomposite membranes (CA-X, CA-X1 and CA-X2). EDAX results showed higher counts of silver at 3keV on the CA-X, confirming that silver nanoparticles were properly embedded on the membrane. Physio-chemical tests performed on the collected sewage, showed that the total dissolved solids (TDS) were found to decrease significantly during the first hour of treatment, CA-X1 showed 16.2% decrease and 21.95% decrease was observed by CA-X2. A decrease in total nitrogen content by 38.88% and 41.36% for CA-X1 and CA-X2 respectively was recorded after a week’s treatment. Therefore, the work displayed the capability of cellulose acetate nanocomposite membrane for leachate treatment, since it displayed its potential in remediating leachate in a short span of time and scalability could be achieved for a larger volume of leachate with larger nanocomposite membranes.
Mostrar más [+] Menos [-]Escalating Trends of Hydrogen Sulphide (H2S) and its Role in Structuring Pakistan Coastal Zones Barren
2024
Kachhi, Kishwar Kumar | Akhter, Najeeb | Panhwar, Sher Khan | Kashani, Imtiaz
The presence of hydrogen sulfide (H2S) gas in the muddy ecosystems is consequence of anthropogenic interference. To understand ecosystem health present study was intended to gauge H2S concentrations involved in annihilation of meiofauna and associated aquatic life from four hotspots including Manora channel, Korangi creeks, Sonmiani, and Bhambhore along the Pakistan coastal belt. Using a handheld gas detector device, it was observed that Bhambhore exhibited lower levels of H2S therefore embraces numerous benthic organisms whereas Manora channel (backwater) and Korangi creek area showed elevated level that does not allow macro-organisms to stay around. The diversity varied across locations, with Bhambhore collecting the most species of mudskippers and Manora creeks collecting the rarest. Overall result of this study reveals that H2S 5~274 ppm is alarming. The data of crabs, mudskippers, fishes, mantis shrimps, shells in relation to the environmental variables of temperature, salinity, conductivity dissolved oxygen and H2S were used to develop canonical correspondence analysis. The variability among first two components was 64.47 and 28.44%, eigenvalue (0.154, 0.068 and trace 0.239) respectively. Considering baseline findings of this study, greater efforts are required for ecosystem resilience for the sake of human health concerns.
Mostrar más [+] Menos [-]Analysis of CO2 Mitigation Strategies for Iran’s Thermal Power Plants Using Modified STIRPAT Model
2024
Maleki, Shadi | Nazari Kudahi, Saeed
Thermal power plants are one of the main sources of CO2 emissions in the world. On the other hand, increasing carbon dioxide emissions as a greenhouse gas is led to global warming and climate change. In this study, CO2 mitigation strategies for Iran’s thermal power plants regarding Intended Nationally Determined Contributions submitted by Iran using modified STIRPAT model examines are presented. In the first step of this research, CO2 emissions from Iran’s power sector are predicted with respect to the parameters including, population, GDP, and electricity generation. In the second step of this research, CO2 mitigation strategies including, using the renewable sources and increasing energy saving as well as power generation efficiency during the years of 2020 to 2025 are analyzed using modified STIRPAT model to reduce carbon dioxide emissions in accordance with Iran’s INDCs. The prediction of carbon dioxide emissions by 2025 represents an increase of 26.5% in carbon dioxide emissions compared to 2017 while estimating carbon dioxide emissions in accordance with Iran’s INDCs allows a maximum increase of 21.4% compared to 2017. In order to reduce carbon dioxide emissions, the average efficiency of power plants by 2025 should be 1.542% higher than in 2017, or 3.086% of the energy savings should be implemented compared to total electricity generation output projected in 2025, or more than 36.22% increment of electricity generation output from renewable energy is expected compared to the projected level in 2025, or a combination of these three solutions.
Mostrar más [+] Menos [-]Satellite-Based Chlorophyll-a Analysis of River Tapi: An Effective Water Quality Management tool with Landsat-8 OLI and Acolite Software
2024
Punde, Bhagavat | Jariwala, Namrata
Most pollutants found in rivers come from the discharge of raw sewage from both point and nonpoint sources. So, monitoring the pollution levels in surface water sources is essential. River pollution monitoring is a real challenge. Using remote sensing, precise outcomes can be achieved with the help of the selection of the right combination of satellite images and algorithms. Generally, established available algorithms are site-specific, indicating that they may not work at all areas on Earth's surface due to differences in altitude, cloud cover, and sun glint. The present work determined Chlorophyll-a concentrations in the Tapi River at various locations using Landsat-8 satellite images and Acolite software from 2017 to 2021 Period. The outcomes reveal that applying the dark spectrum fitting with sun glint correction when processing Landsat-8 satellite images is needed. In the present study, water quality results were obtained very precisely for the months of January, February, November, and December after processing and analysing satellite images. Due to factors such as sun glare, cloud cover, cloud shadow, and haze, the desired effect could not be achieved in the remaining months of the study period. This research provides a solid foundation for estimating the impact of eutrophication in the water body by estimating chlorophyll-a concentration from satellite images.
Mostrar más [+] Menos [-]Removal of Congo Red by Waste Fish Scale: Isotherms, Kinetics, Thermodynamics and Optimization Studies
2024
Roy, Tapas | Mondal, Anupam | Mondal, Naba Kumar
Cong-red dye is a precursor of various products of cotton industry and its toxicity in the aquatic environment is a great concern. Present study was highlighted on the efficacy of the fish scale char (FSC) towards removal of congo red from aqueous solution. The prepared FSC was characterized by zero point charge (pHZPC), scanning electron micrograph with elemental analysis (SEM-EDX) and fourier transform infrared (FTIR). Based in the equilibrium and kinetic study, the Langmuir (R2 = 0.967) and Pseudo-second-order (R2 = 1.00) models are appropriate to describe the dye adsorption process. The randomness and exothermic nature of the system were confirmed by the negative values of both entropy and enthalpy, respectively. Finally, optimization by Response Surface Methodology (RSM) study revealed that the experimental data were nicely fitted with central composite design with very high F value (F = 1596.24, p < 0.0001). Perturbation plot suggested that congo-red dye removal is more sensitive with respect to biosorbent dose, pH and initial concentration. The exhausted adsorbent was regenerated with 0.5(M) NaOH solution. Therefore, it can be concluded that fish scale char could be a valuable materials towards purification of industrial effluent.
Mostrar más [+] Menos [-]The Amine-Functionalized MCM-41 for Hydration and Utilization of CO2
2024
Asadi, Mehdi | Azordeh Molkabadi, Soheila | Engameh, Samaneh
Carbon dioxide, as a great part of greenhouse gases, stands as a major contributor to climate change; hence, various techniques have been presented for controlling and decreasing CO2 emissions. The studies show that the adsorption and conversion into environmentally benign substances are the most practical and efficient strategies for this purpose. As amines are active in CO2 adsorption, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane was chosen as an amine group to functionalize MCM-41 mesoporous in order to hydrate CO2 and convert to calcium carbonate in this study. The synthesis of the mesoporous materials and amine functionalization were carried out using the wet impregnation method, and the materials were characterized by XRD, FT-IR, SEM, and BET analysis. The results demonstrated a high adsorption capacity (165 mg CaCO3) due to the presence of the -NH2 group in the catalysts. Moreover, the results have been compared with similar mesoporous materials functionalized with metals for CO2 capture and hydration. The adsorption-desorption isotherm corresponded to type IV, as defined in the IUPAC classification.
Mostrar más [+] Menos [-]The Effect of Magnetic Treatment on some Physico-Chemical Properties of Landfill Leachate (Wadi Al-Hada)
2024
Ahmad, Adnan | Soubh, Alaa Mohamad
The landfill leachate contains high concentrations of organic pollutants that can be biological and resistant to it. Therefore, the resulting leachate must be treated from the healthy landfill before disposing of it in the environment. In this research, the technique of improved magnetic therapy was tested to improve some physicochemical properties of landfill leachate. Where a laboratory model was designed to evaluate the performance of the magnetic field with different strengths on the treatment of the leachate field collected from the Wadi al-Hadda landfill in Tartous Governorate-Syria. By the increasing in magnetic field strength from 272 to 678 µT, the removal efficacy of BOD and COD increased from 9 and 19% to 36.7 and 54.7%, respectively, and, the removal efficacy of NO3-N and NO3 increased from 6 and 17% to 24.6 and 46.8%, respectively. Electric conductivity (EC) values also decreased due to the use of magnetic field.
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