Removal of Cd(II) from Micro-Polluted Water by Magnetic Core-Shell Fe3O4@Prussian Blue

A novel core-shell magnetic Prussian blue-coated Fe3O4 composites (Fe3O4@PB) were designed and synthesized by in-situ replication and controlled etching of iron oxide (Fe3O4) to eliminate Cd (II) from micro-polluted water. The core-shell structure was confirmed by TEM, and the composites were characterized by XRD and FTIR. The pore diameter distribution from BET measurement revealed the micropore-dominated structure of Fe3O4@PB. The effects of adsorbents dosage, pH, and co-existing ions were investigated. Batch results revealed that the Cd (II) adsorption was very fast initially and reached equilibrium after 4 h. A pH of 6 was favorable for Cd (II) adsorption on Fe3O4@PB. The adsorption rate reached 98.78% at an initial Cd (II) concentration of 100 μg/L. The adsorption kinetics indicated that the pseudo-first-order and Elovich models could best describe the Cd (II) adsorption onto Fe3O4@PB, indicating that the sorption of Cd (II) ions on the binding sites of Fe3O4@PB was the main rate-limiting step of adsorption. The adsorption isotherm well fitted the Freundlich model with a maximum capacity of 9.25 mg·g−1 of Cd (II). The adsorption of Cd (II) on the Fe3O4@PB was affected by co-existing ions, including Cu (II), Ni (II), and Zn (II), due to the competitive effect of the co-adsorption of Cd (II) with other co-existing ions.

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Tertiary amine-catalyzed generation of chlorine dioxide from hypochlorous acid and chlorite ions

Wood Science and Technology ◽

10.1007/s00226-020-01247-5 ◽

2020 ◽

Author(s):

Estefania Isaza Ferro ◽

Jordan Perrin ◽

Owain George John Dawson ◽

Tapani Vuorinen

Keyword(s):

Chlorine Dioxide ◽

Tertiary Amine ◽

Hypochlorous Acid ◽

Suitable Candidate ◽

Rate Limiting Step ◽

Limiting Step ◽

Chlorite Ions ◽

The Stability ◽

Rate Limiting

AbstractThe reaction between hypochlorous acid and chlorite ions is the rate limiting step for in situ chlorine dioxide regeneration. The possibility of increasing the speed of this reaction was analyzed by the addition of tertiary amine catalysts in the system at pH 5. Two amines were tested, DABCO (1,4-diazabicyclo[2.2.2]octane) and its derivative CEM-DABCO (1-carboethoxymethyl-1-azonia-4-aza-bicyclo[2.2.2]octane chloride). The stability of the catalysts in the presence of both reagents and chlorine dioxide was measured, with CEM-DABCO showing to be highly stable with the mentioned chlorine species, whereas DABCO was rapidly degraded by chlorine dioxide. Hence, CEM-DABCO was chosen as a suitable candidate to catalyze the reaction of hypochlorous acid with chlorite ions and it significantly increased the speed of this reaction even at low catalyst dosages. This research opens the door to a faster regeneration of chlorine dioxide and an improved efficiency in chlorine dioxide treatments.

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Increased production of hydrogen with in situ CO2 capture through the process of water splitting using magnetic core/shell structures as novel photocatalysts

Environmental Science and Pollution Research ◽

10.1007/s11356-020-10752-w ◽

2020 ◽

Vol 28 (3) ◽

pp. 3566-3578

Author(s):

Mohamed S.A. Darwish ◽

Ahmed M.A. El Naggar ◽

Asmaa S. Morshedy ◽

Nils Haneklaus

Keyword(s):

Water Splitting ◽

Co2 Capture ◽

Magnetic Core ◽

Shell Structures ◽

Core Shell ◽

Production Of Hydrogen ◽

In Situ Co2 Capture

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Chlorates(VII) removal on Dowex™PSR-2 resin

Annales Universitatis Mariae Curie-Sklodowska sectio AA – Chemia ◽

10.17951/aa.2016.71.1.105 ◽

2016 ◽

Vol 71 (1) ◽

pp. 105

Author(s):

Dorota Kołodyńska ◽

Aleksandra Łyko ◽

Marzena Gęca ◽

Zbigniew Hubicki

Keyword(s):

Solution Concentration ◽

Intraparticle Diffusion ◽

Optimum Conditions ◽

Order Model ◽

Experimental Conditions ◽

Freundlich Model ◽

Rate Limiting Step ◽

Limiting Step ◽

Pseudo Second Order ◽

Rate Limiting

Lately there has been observed the increased presence of chlorates(VII) in the natural environment which can affect human health negatively. Therefore the removal of chlorate(VII) ions using the gel type resin functionalized with the tri-n-butyl ammonium (Dowex™PSR-2) from waters was studied. The main aim was to evaluate the effects of experimental conditions including contact time, initial solution concentration, pH and temperature on chlorate(VII) ions removal as well as the anion exchanger properties on chlorate(VII) ions sorption. It was found that only the pseudo second order model described the experimental data well and the intraparticle diffusion was not the rate-limiting step. According to the Freundlich model, the qe value was to be 69.26 mg/g at optimum conditions (pH 7.0 at 25 oC).

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In Situ Self‐Assembly of Core–Shell Multimetal Prussian Blue Analogues for High‐Performance Sodium‐Ion Batteries

ChemSusChem ◽

10.1002/cssc.201902013 ◽

2019 ◽

Vol 12 (21) ◽

pp. 4786-4790 ◽

Cited By ~ 6

Author(s):

Jinwen Yin ◽

Yi Shen ◽

Chang Li ◽

Chenyang Fan ◽

Shixiong Sun ◽

...

Keyword(s):

Prussian Blue ◽

Self Assembly ◽

High Performance ◽

Sodium Ion ◽

Core Shell ◽

Sodium Ion Batteries ◽

Prussian Blue Analogues

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In-situ growth of Cu@CuFe Prussian blue based core-shell nanowires for non-enzymatic electrochemical determination of ascorbic acid with high sensitivity and reusability

Journal of Electroanalytical Chemistry ◽

10.1016/j.jelechem.2021.115718 ◽

2021 ◽

pp. 115718

Author(s):

Jingyu Feng ◽

Yu Liu ◽

Yuansheng Shan ◽

Ying Xie ◽

Zhenyu Chu ◽

...

Keyword(s):

Ascorbic Acid ◽

Prussian Blue ◽

High Sensitivity ◽

Electrochemical Determination ◽

Core Shell ◽

In Situ Growth ◽

Shell Nanowires

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A Molecular Dynamics Study of Primary Production from Shale Organic Pores

SPE Journal ◽

10.2118/201198-pa ◽

2020 ◽

Vol 25 (05) ◽

pp. 2521-2533 ◽

Cited By ~ 1

Author(s):

Felipe Perez ◽

Deepak Devegowda

Keyword(s):

Fluid Transport ◽

Pore Diameter ◽

Fluid Model ◽

Fluid Composition ◽

Hydrocarbon Production ◽

Rate Limiting Step ◽

Wet Gas ◽

Rate Limiting ◽

Organic Pores

Summary We created a model of mature kerogen saturated with a black oil. Our fluid model spans light, intermediate, and long alkane chains; and aromatics, asphaltenes, and resins. The maximum pore diameter of our kerogen model is 2.5 nm. The insertion of a microfracture in the system allows us to study fluid transport from kerogen to the microfracture, which is the rate-limiting step in hydrocarbon production from shales. Our results indicate that the composition of the produced fluids changes with time, transitioning from a dry/wet gas to a gas condensate, becoming heavier with time. However, at any given time, the produced fluid is significantly lighter than the in-situ fluid. The species with the greatest mobility is methane, which is expected because it is the lightest molecule in the fluid and its ability to migrate is greater than that of all other fluid molecules. A sensitivity analysis shows that the produced fluid composition strongly depends on the initial composition of the fluids in organic pores.

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Spatial Distribution of PCB Dechlorinating Bacteria and Activities in Contaminated Soil

Applied and Environmental Soil Science ◽

10.1155/2012/584970 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 17

Author(s):

Birthe V. Kjellerup ◽

Piuly Paul ◽

Upal Ghosh ◽

Harold D. May ◽

Kevin R. Sowers

Keyword(s):

Soil Aggregates ◽

Soil Samples ◽

Time Analysis ◽

Baltimore Harbor ◽

Rate Limiting Step ◽

Dechlorinating Bacteria ◽

Pcb Dechlorination ◽

Rate Limiting ◽

Aerobic And Anaerobic

Soil samples contaminated with Aroclor 1260 were analyzed for microbial PCB dechlorination potential, which is the rate-limiting step for complete PCB degradation. The average chlorines per biphenyl varied throughout the site suggesting that different rates ofin situdechlorination had occurred over time. Analysis of PCB transforming (aerobic and anaerobic) microbial communities and dechlorinating potential revealed spatial heterogeneity of both putative PCB transforming phylotypes and dechlorination activity. Some soil samples inhibited PCB dechlorination in active sediment from Baltimore Harbor indicating that metal or organic cocontaminants might cause the observed heterogeneity ofin situdechlorination. Bioaugmentation of soil samples contaminated with PCBs ranging from 4.6 to 265 ppm with a pure culture of the PCB dechlorinating bacteriumDehalobium chlorocoerciaDF-1 also yielded heterologous results with significant dechlorination of weathered PCBs observed in one location. The detection of indigenous PCB dehalorespiring activity combined with the detection of putative dechlorinating bacteria and biphenyl dioxygenase genes in the soil aggregates suggests that the potential exists for complete mineralization of PCBs in soils. However, in contrast to sediments, the heterologous distribution of microorganisms, PCBs, and inhibitory cocontaminants is a significant challenge for the development ofin situmicrobial treatment of PCB impacted soils.

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Interactions of Polysilicon with Aluminum

MRS Proceedings ◽

10.1557/proc-106-163 ◽

1987 ◽

Vol 106 ◽

Author(s):

G. Ottaviani ◽

K. N. Tu ◽

C. Nobili

Keyword(s):

Energy Difference ◽

Aluminum Film ◽

Isothermal Treatment ◽

Final States ◽

X Ray Diffraction ◽

Free Energy Difference ◽

Rate Limiting Step ◽

Constant Heating ◽

Rate Limiting

ABSTRACTIn-situ resistivity measurements togheter with Auger electron spectroscopy, MeV 4He+ backscattering spectrometry, scanning electron microscope and x-ray diffraction have been used to investigate interactions between Al films and CVD polycristalline silicon layers deposited on thermally grown SiO2 on silicon. A sharp and well defined increase in resistivity around 450 °C has been associated to the erosion of the polysilicon and growth of Si crystallites in the metal film. The kinetic of the transformation has been studied by isothermal treatment over the 390–450 °C temperature range. An activation energy of 2.2 ± 0.2 eV has been measured. Similar results have been obtained by using treatments at constant heating rate. A critical analysis of the available data suggests that the rate limiting step is the nucleation of Si grains in the aluminum film. The driving force for the process can be identified to be the free energy difference between the initial and final states.

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