Ferrous Magnetic Nanoparticles for Arsenic Removal from Groundwater

Arsenic in water is currently a global concern due to the long-term exposure that could affect human health. In this study, magnetic nanoparticles (MNPs), CoFe2O4, and MnFe2O4 were successfully synthesized and applied to remove arsenic (As) from water. The MNPs were characterized using different techniques, such as scanning electron microscope (SEM), Brunauer–Emmet–Teller (BET), and photoelectron spectroscopy (XPS). The nanoscale size and the specific surface area achieved a fast, selective, and high As adsorption capacity. MNPs have a mesoporous structure with a mean pore diameter of 5 nm and a mean particle size of 30 nm. The adsorption capacity of these MNPs was determined through kinetic and equilibrium experiments, multilayer adsorption that obeyed the Freundlich model equation was observed, and the maximum adsorption capacities reached were 250 mg/g for CoFe2O4 and 230 mg/g for MnFe2O4. Furthermore, MNPs characteristics like regeneration and reuse, several pH tolerances, non-ion interference, and effective As removal from groundwater samples confirms the nanomaterials’ potential for future applications in water treatment systems combined with magnetic separation.

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Fe-FeS2 adsorbent prepared with iron powder and pyrite by facile ball milling and its application for arsenic removal

Water Science & Technology ◽

10.2166/wst.2017.204 ◽

2017 ◽

Vol 76 (1) ◽

pp. 192-200 ◽

Cited By ~ 41

Author(s):

Xiaobo Min ◽

Yangwenjun Li ◽

Yong Ke ◽

Meiqing Shi ◽

Liyuan Chai ◽

...

Keyword(s):

Adsorption Capacity ◽

Ball Milling ◽

Photoelectron Spectroscopy ◽

Arsenic Removal ◽

Molar Ratio ◽

Arsenic Adsorption ◽

Arsenic Uptake ◽

X Ray ◽

Before And After ◽

High Arsenic

Arsenic is one of the major pollutants and a worldwide concern because of its toxicity and chronic effects on human health. An adsorbent of Fe-FeS2 mixture for effective arsenic removal was successfully prepared by mechanical ball milling. The products before and after arsenic adsorption were characterized with scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorbent shows high arsenic removal efficiency when molar ratio of iron to pyrite is 5:5. The experimental data of As(III) adsorption are fitted well with the Langmuir isotherm model with a maximal adsorption capacity of 101.123 mg/g. And As(V) data were described perfectly by the Freundlich model with a maximal adsorption capacity of 58.341 L/mg. As(III) is partial oxidized to As(V) during the adsorption process. High arsenic uptake capability and cost-effectiveness of waste make it potentially attractive for arsenic removal.

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Distribution of Enteric Viruses and Microorganisms in Long-Term Sewage-Treated Soil

Water Science & Technology ◽

10.2166/wst.1983.0046 ◽

1983 ◽

Vol 15 (5) ◽

pp. 129-135 ◽

Cited By ~ 2

Author(s):

Z Filip ◽

K Seidel ◽

H Dizer

Keyword(s):

Soil Bacteria ◽

Pathogenic Bacteria ◽

Sewage Treatment ◽

Anaerobic Bacteria ◽

Enteric Viruses ◽

Sewage Irrigation ◽

Groundwater Samples ◽

West Berlin ◽

Aerobic Soil

To determine whether long-term sewage treatment can take place without a pollution risk for soil and groundwater, samples from sewage irrigation fields in West Berlin which have been in use since about 1890 were analyzed for enteric viruses and microorganisms. Enteric viruses were detected in only seven samples from a total number of eighty seven taken from different soil depths. With only one exception, no viruses were found below 60 cm. No viruses were detected in groundwater samples. Long-term sewage irrigation did not result in significant changes in the colony courts of aerobic soil bacteria, but the counts of anaerobic bacteria and actinomycetes were slightly elevated and those of microscopic fungi slightly decreased. Potentially pathogenic bacteria were not detected in soil below 90 cm.

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Seabird bycatch vulnerability in pelagic longline fisheries based on modelling of a long-term dataset

Bird Conservation International ◽

10.1017/s0959270921000046 ◽

2021 ◽

pp. 1-16

Author(s):

CAN ZHOU ◽

NIGEL BROTHERS

Keyword(s):

Capture Event ◽

Retrieval Rate ◽

Competitive Environments ◽

Global Concern ◽

Competitive Species ◽

Spatio Temporal ◽

Longline Fisheries ◽

Pelagic Longline

Summary The incidental mortality of seabirds in fisheries remains a serious global concern. Obtaining unbiased and accurate estimates of bycatch rates is a priority for seabird bycatch mitigation and demographic research. For measuring the capture risk of seabird interactions in fisheries, the rate of carcass retrieval from hauled gear is commonly used. However, reliability can be limited by a lack of direct capture observations and the substantial pre-haul bycatch losses known to occur, meaning incidence of seabird bycatch is underestimated. To solve this problem, a new measure (bycatch vulnerability) that links an observed interaction directly to the underlying capture event is proposed to represent the capture risk of fishery interactions by seabirds. The new measure is not affected by subsequent bycatch loss. To illustrate how to estimate and analyse bycatch vulnerability, a case study based on a long-term dataset of seabird interactions and capture confirmation is provided. Bayesian modelling and hypothesis testing were conducted to identify important bycatch risk factors. Competition was found to play a central role in determining seabird bycatch vulnerability. More competitive environments were riskier for seabirds, and larger and thus more competitive species were more at risk than smaller sized and less competitive species. Species foraging behaviour also played a role. On the other hand, no additional effect of physical oceanic condition and spatio-temporal factors on bycatch vulnerability was detected. Bycatch vulnerability is recommended as a replacement for the commonly used bycatch rate or carcass retrieval rate to measure the capture risk of an interaction. Combined with a normalized contact rate, bycatch vulnerability offers an unbiased estimate of seabird bycatch rate in pelagic longline fisheries.

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Pristine and Magnetic Kenaf Fiber Biochar for Cd2+ Adsorption from Aqueous Solution

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18157949 ◽

2021 ◽

Vol 18 (15) ◽

pp. 7949

Author(s):

Anwar Ameen Hezam Saeed ◽

Noorfidza Yub Harun ◽

Suriati Sufian ◽

Muhammad Roil Bilad ◽

Zaki Yamani Zakaria ◽

...

Keyword(s):

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Textural Properties ◽

Ion Concentration ◽

Solution Temperature ◽

Maximum Adsorption Capacity ◽

Magnetic Biochar ◽

X Ray ◽

Study Results ◽

Capacity Surface

Development of strategies for removing heavy metals from aquatic environments is in high demand. Cadmium is one of the most dangerous metals in the environment, even under extremely low quantities. In this study, kenaf and magnetic biochar composite were prepared for the adsorption of Cd2+. The synthesized biochar was characterized using (a vibrating-sample magnetometer VSM), Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The adsorption batch study was carried out to investigate the influence of pH, kinetics, isotherm, and thermodynamics on Cd2+ adsorption. The characterization results demonstrated that the biochar contained iron particles that help in improving the textural properties (i.e., surface area and pore volume), increasing the number of oxygen-containing groups, and forming inner-sphere complexes with oxygen-containing groups. The adsorption study results show that optimum adsorption was achieved under pH 5–6. An increase in initial ion concentration and solution temperature resulted in increased adsorption capacity. Surface modification of biochar using iron oxide for imposing magnetic property allowed for easy separation by external magnet and regeneration. The magnetic biochar composite also showed a higher affinity to Cd2+ than the pristine biochar. The adsorption data fit well with the pseudo-second-order and the Langmuir isotherm, with the maximum adsorption capacity of 47.90 mg/g.

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Changes in surface characteristics and adsorption properties of 2,4,6-trichlorophenol following Fenton-like aging of biochar

Scientific Reports ◽

10.1038/s41598-021-82129-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Liqiang Cui ◽

Qinya Fan ◽

Jianxiong Sun ◽

Guixiang Quan ◽

Jinlong Yan ◽

...

Keyword(s):

Adsorption Capacity ◽

Surface Properties ◽

Aging Process ◽

Surface Characteristics ◽

Natural Soil ◽

Peanut Shell ◽

Soil Environment ◽

Polluted Soils ◽

Physico Chemical

AbstractFenton-like system formed in a natural soil environment deemed to be significant in the aging process of biochar. Aged biochars have distinct physico-chemical and surface properties compared to non-aged biochar. The aged biochar proved to be useful soil amendment due to its improved elements contents and surface properties. The biochar aging process resulted in increased surface area and pore volume, as well as carbon and oxygen-containing functional groups (such as C=O, –COOH, O–C=O etc.) on its surface, which were also associated with the adsorption behavior of 2,4,6-trichlorophenol (2,4,6-TCP). The biochar aging increased the adsorption capacity of 2,4,6-TCP, which was maximum at pH 3.0. The 2,4,6-TCP adsorption capacity of aged-bush biochar (ABB) and aged-peanut shell biochar (APB) was increased by 1.0–11.0% and 7.4–38.8%, respectively compared with bush biochar (BB) and peanut shell biochar (PB) at the same initial concentration of 2,4,6-TCP. All biochars had similar 2,4,6-TCP desorption rates ranging from 33.2 to 73.3% at different sorption temperatures and times. The desorbed components were mainly 2,4,6-TCP and other degraded components, which were low in concentration with small molecule substance. The results indicated that the aged-biochar could be effective for the long-term remediation of naturally organic polluted soils.

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Fabrication of Carboxymethylcellulose/Metal-Organic Framework Beads for Removal of Pb(II) from Aqueous Solution

Materials ◽

10.3390/ma12060942 ◽

2019 ◽

Vol 12 (6) ◽

pp. 942 ◽

Cited By ~ 10

Author(s):

Huo-Xi Jin ◽

Hong Xu ◽

Nan Wang ◽

Li-Ye Yang ◽

Yang-Guang Wang ◽

...

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Langmuir Isotherm ◽

Adsorption Equilibrium ◽

Isotherm Model ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Metal Organic ◽

Langmuir Isotherm Model

The ability to remove toxic heavy metals, such as Pb(II), from the environment is an important objective from both human-health and ecological perspectives. Herein, we describe the fabrication of a novel carboxymethylcellulose-coated metal organic material (MOF-5–CMC) adsorbent that removed lead ions from aqueous solutions. The adsorption material was characterized by Fourier-transform infrared spectroscopy, X-ray diffractometry, scanning electron microscopy, and X-ray photoelectron spectroscopy. We studied the functions of the contact time, pH, the original concentration of the Pb(II) solution, and adsorption temperature on adsorption capacity. MOF-5–CMC beads exhibit good adsorption performance; the maximum adsorption capacity obtained from the Langmuir isotherm-model is 322.58 mg/g, and the adsorption equilibrium was reached in 120 min at a concentration of 300 mg/L. The adsorption kinetics is well described by pseudo-second-order kinetics, and the adsorption equilibrium data are well fitted to the Langmuir isotherm model (R2 = 0.988). Thermodynamics experiments indicate that the adsorption process is both spontaneous and endothermic. In addition, the adsorbent is reusable. We conclude that MOF-5–CMC is a good adsorbent that can be used to remove Pb(II) from aqueous solutions.

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Mechanical Properties of Epoxy Adhesive Under Thermal Aging and Their Chemical Degradation Behavior

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19424 ◽

2021 ◽

Vol 21 (8) ◽

pp. 4444-4449

Author(s):

Bongjin Chung ◽

Shin Sungchul ◽

Jaeho Shim ◽

Seongwoo Ryu

Keyword(s):

Mechanical Properties ◽

Thermal Aging ◽

Photoelectron Spectroscopy ◽

Thermal Exposure ◽

Chain Scission ◽

Epoxy Adhesive ◽

Chemical Degradation ◽

Adhesive Properties ◽

Noticeable Reduction

Epoxy adhesive was analyzed under long term thermal aging and mechanical properties and chemical degradation were observed by X-ray photoelectron spectroscopy (XPS). Long term thermal exposure of epoxy causes a noticeable reduction in adhesive properties. We developed a predictive model of temperature and time dependent aging. The temperature dependent aging behavior of epoxy adhesive shows good agreement with conventional Arrhenius equations. Using XPS analysis, we also discovered a correlation between chemical degradation and the adhesive properties. Decay of C–C bonding ratio induced chain-scission of epoxy adhesive; increase of total numbers of C–O and C═O induced oxidation of epoxy adhesive during thermal exposure.

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Samples disturbance overestimates phosphorus adsorption capacity in soils under long-term application of pig slurry

Archives of Agronomy and Soil Science ◽

10.1080/03650340.2018.1562274 ◽

2019 ◽

Vol 65 (9) ◽

pp. 1262-1272 ◽

Cited By ~ 2

Author(s):

Luciano Colpo Gatiboni ◽

Djalma Eugênio Schmitt ◽

Paulo Cezar Cassol ◽

Jucinei José Comin ◽

Joice Crescêncio Heidemann ◽

...

Keyword(s):

Adsorption Capacity ◽

Pig Slurry ◽

Phosphorus Adsorption

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Point-of-Use Detection of Environmental Fluoride via a Cell-Free Riboswitch-Based Biosensor

10.1101/712844 ◽

2019 ◽

Cited By ~ 2

Author(s):

Walter Thavarajah ◽

Adam D. Silverman ◽

Matthew S. Verosloff ◽

Nancy Kelley-Loughnane ◽

Michael C. Jewett ◽

...

Keyword(s):

Water Source ◽

Free System ◽

Molecular Systems ◽

Long Term Storage ◽

Point Of Use ◽

Regulatory Standard ◽

A Cell ◽

Global Concern ◽

Dna Template

AbstractAdvances in biosensor engineering have enabled the design of programmable molecular systems to detect a range of pathogens, nucleic acids, and chemicals. Here, we engineer and field-test a biosensor for fluoride, a major groundwater contaminant of global concern. The sensor consists of a cell-free system containing a DNA template that encodes a fluoride-responsive riboswitch regulating genes that produce a fluorescent or colorimetric output. Individual reactions can be lyophilized for long-term storage and detect fluoride at levels above 2 parts per million, the EPA’s most stringent regulatory standard, in both laboratory and field conditions. Through onsite detection of fluoride in a real-world water source, this work provides a critical proof-of-principle for the future engineering of riboswitches and other biosensors to address challenges for global health and the environment.

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Empowering Theory of Poverty Reduction for Sustainable Development: Does the Welfare of Descendants Matter?

Problemy Ekorozwoju ◽

10.35784/pe.2022.1.05 ◽

2022 ◽

Vol 17 (1) ◽

pp. 52-63

Author(s):

Juliusz Piwowarski ◽

◽

Larysa Yankovska ◽

Bohdan-Petro Koshovyi ◽

Ira Von-Nagy ◽

...

Keyword(s):

Sustainable Development ◽

Poverty Reduction ◽

Sustainable Development Goals ◽

Poverty Eradication ◽

Sustainable Development Goal ◽

The Future ◽

Development Goals ◽

Global Concern ◽

Valid Form

The first Sustainable Development Goal expresses the global concern in poverty eradication. We looked at the theory of poverty reduction with a long-term perspective in mind to confirm the congruence of modern approaches and their compliance with the principles of sustainable development. Despite clear signs of targeting Sustainable development goals to the future, we have found that future poverty needs deep discussion. We researched legal acts, policies and scientific sources to prove the possibility and suitability of recognising future poverty as a valid form of poverty. We considered the main possible difficulties that will challenge initiatives of future poverty exhausting. Finally, we proposed several perspective directions of further research to include the future poverty concept into the agenda of governments and supranational organisations.

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