Fabrication of Mg-Doped Sargassum Biochar for Phosphate and Ammonium Recovery

Biochars prepared from macro-algae have a lower C/N ratio compared to lignocellulosic biochar, which is advantageous for direct nutrition. In particular, Sargassum, a marine macro-algae, has a high Mg content; hence, it can be expected to adsorb P and N simultaneously. In this study, Sargassum horneri biochar (SB), pyrolyzed at 400, 500, and 600 °C, was doped with innate Mg through water leaching, and nutrient recovery from the wastewater-mimicking solution was confirmed. The biochar pyrolyzed at 600 °C showed maximum Mg adsorption during water leaching, and the efficiency of K and Na removal was also high, at 92.7% and 91.9%, respectively. The addition of MgCl2 during pyrolysis and high ion exchange did not show distinct advantages for surface modification and nutrient adsorption. X-ray photoelectron spectroscopy analysis confirmed the participation of biochar in the surface adsorption of Mg and PO4 recovery. The PO4 sorption capacity of biochar reached >120 mg·g−1, while the sorption capacity for NH4 was low, at 22.8–28.2 mg·g−1, suggesting that Mg-surface-doped SB presented excellent phosphorus recovery. Hence, upgrading an adsorbent as a wastewater-treatment material and soil ameliorant that recovers nutrients using innate Mg from Sargassum is possible through appropriate surface modification.

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X-ray photoelectron spectroscopy analysis on surface modification of Konjac glucomannan membrane by nitrogen plasma treatment

Carbohydrate Polymers ◽

10.1016/j.carbpol.2011.12.013 ◽

2012 ◽

Vol 88 (1) ◽

pp. 369-372 ◽

Cited By ~ 14

Author(s):

Jie Pang ◽

Wenjie Jian ◽

Liangyu Wang ◽

Chunhua Wu ◽

Yanan Liu ◽

...

Keyword(s):

Surface Modification ◽

Plasma Treatment ◽

Photoelectron Spectroscopy ◽

Nitrogen Plasma ◽

Konjac Glucomannan ◽

Spectroscopy Analysis ◽

X Ray

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Effects of Thermal Annealing on the Properties of Zirconium-Doped MgxZn1−XO Films Obtained through Radio-Frequency Magnetron Sputtering

Membranes ◽

10.3390/membranes11050373 ◽

2021 ◽

Vol 11 (5) ◽

pp. 373

Author(s):

Wen-Yen Lin ◽

Feng-Tsun Chien ◽

Hsien-Chin Chiu ◽

Jinn-Kong Sheu ◽

Kuang-Po Hsueh

Keyword(s):

Magnetron Sputtering ◽

Radio Frequency ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

Free Electrons ◽

X Ray ◽

Mg Content

Zirconium-doped MgxZn1−xO (Zr-doped MZO) mixed-oxide films were investigated, and the temperature sensitivity of their electric and optical properties was characterized. Zr-doped MZO films were deposited through radio-frequency magnetron sputtering using a 4-inch ZnO/MgO/ZrO2 (75/20/5 wt%) target. Hall measurement, X-ray diffraction (XRD), transmittance, and X-ray photoelectron spectroscopy (XPS) data were obtained. The lowest sheet resistance, highest mobility, and highest concentration were 1.30 × 103 Ω/sq, 4.46 cm2/Vs, and 7.28 × 1019 cm−3, respectively. The XRD spectra of the as-grown and annealed Zr-doped MZO films contained MgxZn1−xO(002) and ZrO2(200) coupled with Mg(OH)2(101) at 34.49°, 34.88°, and 38.017°, respectively. The intensity of the XRD peak near 34.88° decreased with temperature because the films that segregated Zr4+ from ZrO2(200) increased. The absorption edges of the films were at approximately 348 nm under 80% transmittance because of the Mg content. XPS revealed that the amount of Zr4+ increased with the annealing temperature. Zr is a potentially promising double donor, providing up to two extra free electrons per ion when used in place of Zn2+.

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X‐ray photoelectron spectroscopy analysis of photostimulated chemical vapor deposition hydrogenated amorphous silicon/amorphous aluminum oxide

Applied Physics Letters ◽

10.1063/1.107407 ◽

1992 ◽

Vol 60 (10) ◽

pp. 1208-1210 ◽

Cited By ~ 1

Author(s):

K. Uwasawa ◽

F. Ishihara ◽

S. Matsumoto

Keyword(s):

Chemical Vapor Deposition ◽

Aluminum Oxide ◽

Amorphous Silicon ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Hydrogenated Amorphous Silicon ◽

Chemical Vapor ◽

Spectroscopy Analysis ◽

X Ray ◽

Hydrogenated Amorphous

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X-ray photoelectron spectroscopy and positron annihilation spectroscopy analysis of surfactant affected FePt spintronic films

Applied Surface Science ◽

10.1016/j.apsusc.2014.04.190 ◽

2014 ◽

Vol 308 ◽

pp. 408-413 ◽

Cited By ~ 1

Author(s):

Chun Feng ◽

Xujing Li ◽

Fen Liu ◽

Qiang Wang ◽

Meiyin Yang ◽

...

Keyword(s):

Positron Annihilation ◽

Photoelectron Spectroscopy ◽

Positron Annihilation Spectroscopy ◽

Spectroscopy Analysis ◽

X Ray

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SiO2 films as heat resistant layers for protection of expandable polystyrene foam from flame torch–induced heat

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717718238 ◽

2017 ◽

Vol 31 (5) ◽

pp. 657-667 ◽

Cited By ~ 1

Author(s):

S Varnagiris ◽

S Tuckute ◽

M Lelis ◽

D Milcius

Keyword(s):

Heat Resistance ◽

Photoelectron Spectroscopy ◽

Silicon Oxide ◽

Plasma Generator ◽

Expanded Polystyrene ◽

Spectroscopy Analysis ◽

X Ray ◽

Heat Resistant ◽

Pulsed Dc ◽

Gas Atmosphere

Currently, polymeric insulation materials are widely used for energy saving in buildings. Despite of all benefits, these materials are generally sensitive to heat and highly flammable. This work discusses possibility to improve heat resistance of expanded polystyrene (EPS) foam using thin silicon dioxide (SiO2) films deposited by magnetron sputtering technique. In order to increase surface energy and adherence of SiO2 thin films to substrate EPS was plasma pretreated before films’ depositions using pulsed DC plasma generator for 40 s in argon gas. SiO2 formation was done in reactive argon and oxygen gas atmosphere. Laboratory made equipment was used for flame torch–induced heat resistance experiments. Results showed that silicon oxide films remains stable during heat resistance experiments up to 5 s and fully protects polystyrene (PS) substrate. Films are relatively stable for 30 s and 60 s and partially protect PS from melting and ignition. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy analysis confirmed that SiO2 layer, which is distributed uniformly on the EPS surface, could work as a good heat resistant material.

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Removal of Pb(II) and Cu(II) from aqueous solution using multiwalled carbon nanotubes/iron oxide magnetic composites

Water Science & Technology ◽

10.2166/wst.2011.270 ◽

2011 ◽

Vol 63 (5) ◽

pp. 917-923 ◽

Cited By ~ 46

Author(s):

Jun Hu ◽

Donglin Zhao ◽

Xiangke Wang

Keyword(s):

Carbon Nanotubes ◽

Iron Oxide ◽

Multiwalled Carbon Nanotubes ◽

Sorption Capacity ◽

Photoelectron Spectroscopy ◽

Metal Ion ◽

Precipitation Method ◽

Multiwalled Carbon ◽

Magnetic Composites ◽

X Ray

Multiwalled carbon nanotubes (MWCNTs)/iron oxide magnetic composites (named as MCs) were prepared by co-precipitation method, and were characterised by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) in detail. The prepared MCs were employed as an adsorbent for the removal of Pb(II) and Cu(II) ions from wastewater in heavy metal ion pollution cleanup. The results demonstrated that the sorption of Pb(II) and Cu(II) ions was strongly dependent on pH and temperature. The experimental data were well described by Langmuir model, and the monolayer sorption capacity of MCs was found to vary from 10.02 to 31.25 mg/g for Pb(II) and from 3.11 to 8.92 mg/g for Cu(II) at temperature increasing from 293.15 to 353.15 K at pH 5.50. The sorption capacity of Pb(II) on MCs was higher than that of Cu(II), which was attributed to their ionic radius, hydration energies and hydrolysis of their hydroxides. The thermodynamic parameters (i.e., ΔH0, ΔS0 and ΔG0) were calculated from temperature dependent sorption isotherms, and the results indicated that the sorption of Pb(II) and Cu(II) ions on MCs were spontaneous and endothermic processes.

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Effect of Sodium Metabisulfite on Selective Flotation of Chalcopyrite and Molybdenite

Minerals ◽

10.3390/min11121377 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1377

Author(s):

Yuki Semoto ◽

Gde Pandhe Wisnu Suyantara ◽

Hajime Miki ◽

Keiko Sasaki ◽

Tsuyoshi Hirajima ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Separation Efficiency ◽

Diesel Oil ◽

Sodium Metabisulfite ◽

Depressing Effect ◽

Spectroscopy Analysis ◽

X Ray ◽

Selective Flotation

Sodium metabisulfite (MBS) was used in this study for selective flotation of chalcopyrite and molybdenite. Microflotation tests of single and mixed minerals were performed to assess the floatability of chalcopyrite and molybdenite. The results of microflotation of single minerals showed that MBS treatment significantly depressed the floatability of chalcopyrite and slightly reduced the floatability of molybdenite. The results of microflotation of mixed minerals demonstrated that the MBS treatment could be used as a selective chalcopyrite depressant in the selective flotation of chalcopyrite and molybdenite. Furthermore, the addition of diesel oil or kerosene could significantly improve the separation efficiency of selective flotation of chalcopyrite and molybdenite using MBS treatment. A mechanism based on X-ray photoelectron spectroscopy analysis results is proposed in this study to explain the selective depressing effect of MBS on the flotation of chalcopyrite and molybdenite.

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