Adsorption of As(V) by the Novel and Efficient Adsorbent Cerium-Manganese Modified Biochar

Arsenic has become a global concern in water environment, and it is essential to develop efficient remediation methods. In this study, a novel adsorbent by loading cerium and manganese oxide onto wheat straw-modified biochar (MBC) was manufactured successfully aiming to remove arsenic from polluted water. Through scanning electron microscopy and energy-dispersive spectroscopy (SEM-EDS), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometer (FT-IR), and other techniques, it was found the loading of cerium and manganese oxide on MBC played a significant role in As(V) adsorption. The results of the batch test showed that the adsorption of MBC followed the pseudo-second order kinetics and Langmuir equation. The adsorption capacity of MBC was 108.88 mg As(V)/g at pH = 5.0 (C0 = 100 mg/L, dosage = 0.5 g/L, T = 298 K) with considerable improvement compared to the original biochar. Moreover, MBC exhibited excellent performance over a wide pH range (2.0~11.0). Thermodynamics of the sorption reaction showed that the entropy (ΔS), changes of enthalpy (ΔH) and Gibbs free energy (ΔG), respectively, were 85.88 J/(moL·K), 22.54 kJ/mol and −1.33 to −5.20 kJ/mol at T = 278~323 K. During the adsorption, the formation of multiple complexes under the influence of its abundant surface M-OH (M represents the Ce/Mn) groups involving multiple mechanisms that included electrostatic interaction forces, surface adsorption, redox reaction, and surface complexation. This study indicated that MBC is a promising adsorbent to remove As(V) from polluted water and has great potential in remediating of arsenic contaminated environment.

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Enhanced removal of hexavalent chromium by different acid-modified biochar derived from corn straw: behavior and mechanism

Water Science & Technology ◽

10.2166/wst.2020.290 ◽

2020 ◽

Vol 81 (10) ◽

pp. 2270-2280

Author(s):

Yonggang Xu ◽

Tianxia Bai ◽

Yubo Yan ◽

Yunfeng Zhao ◽

Ling Yuan ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Hydrogen Ion ◽

Corn Straw ◽

Order Model ◽

Freundlich Model ◽

X Ray ◽

Modified Biochar ◽

Before And After ◽

Pseudo Second Order ◽

Kinetics Of

Abstract It is of great significance to remove Cr(VI) from water as a result of its high toxicity. Biochar from corn straw was modified by different acids (HNO3, H2SO4 and H3PO4) to remove Cr(VI) from aqueous solution. To estimate the removal mechanisms of Cr(VI) by the acid-modified biochars, batch experiments were performed in the light of contact time, Cr(VI) concentration, and pH, and the characteristics of acid-modified biochars before and after Cr(VI) adsorption were investigated by Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics of Cr(VI) by acid-modified biochars were consistent with the pseudo-second-order model, and the adsorption isotherm obeyed the Freundlich model. Furthermore, the acid- modified biochars could supply more oxygen-containing functional groups (-COOH and -OH) as electron donor (e−) and hydrogen ion (H+) to enhance the reduction of Cr(VI) to Cr(III), resulting in enhanced removal of Cr(VI). HNO3-modified biochar exhibited the highest removal efficiency of Cr(VI). In general, the acid modifition of biochar was an effective method to increase the removal of Cr(VI).

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Synthesis of 1-(2-Hydroxyphenyl) Dec-2-en-1-One Oxime and Its Flotation and Adsorption Behavior for Malachite

Frontiers in Chemistry ◽

10.3389/fchem.2020.592771 ◽

2020 ◽

Vol 8 ◽

Author(s):

Liqing Li ◽

Lin Yang ◽

Fangxu Li

Keyword(s):

Photoelectron Spectroscopy ◽

Adsorption Behavior ◽

Xps Analysis ◽

X Ray ◽

Benzohydroxamic Acid ◽

Wide Ph Range ◽

Flotation Performance ◽

Ph Range

A novel collector of 1-(2-hydroxyphenyl) dec-2-en-1-one oxime (HPDO) was synthesized from 2-hydroxy acetophenone and octanal, and its flotation and adsorption behavior for malachite were studied by flotation tests and x-ray photoelectron spectroscopy (XPS) analysis. The flotation results of a single mineral show HPDO is a special collector for malachite. Compared with benzohydroxamic acid (BHA), isobutyl xanthate (SIBX), and dodecylamine (DA), HPDO exhibits excellent flotation performance for malachite and satisfied selectivity against quartz and calcite over a wide pH range. The HPDO with a concentration of 200 mg/L can float 94% malachite at pH 8, while only recovering 7.8% quartz and 28% calcite. XPS data give clear evidence for the formation of a Cu-oxime complex on malachite surfaces after HPDO adsorption.

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Hydrothermally Reduced Graphene Hydrogel Intercalated with Divalent Ions for Dye Adsorption Studies

Processes ◽

10.3390/pr9010169 ◽

2021 ◽

Vol 9 (1) ◽

pp. 169

Author(s):

Alvin Lim Teik Zheng ◽

Supakorn Boonyuen ◽

Teruhisa Ohno ◽

Yoshito Andou

Keyword(s):

Surface Area ◽

Photoelectron Spectroscopy ◽

Dye Adsorption ◽

Textural Properties ◽

Diffusion Kinetic ◽

X Ray ◽

Dye Pollutants ◽

Reduced Graphene ◽

Infrared Spectrometer ◽

Pseudo Second Order

Fundamental studies involving divalent ion intercalated graphene-based hydrogel are still lacking in terms of their adsorption behavior towards dye pollutants. In this study, we prepared a self-assembled Mg2+ and Ca2+ intercalated reduced graphene hydrogel (rGH) using hydrothermal treatment to evaluate the intercalation impact on the adsorption capability towards cationic dyes, methylene blue and rhodamine B. The morphological, structural, thermal, and textural properties of the divalent ion intercalated reduced graphene hydrogels were studied using Fourier transform infrared spectrometer, thermogravimetric analysis, Raman spectroscopy, scanning electron microscope-energy dispersive spectroscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller surface area analysis, and X-ray diffraction. The increased adsorption capacity of the divalent ion intercalated reduced graphene-based hydrogels towards the dye molecules resulted from the increase in the specific surface area and pore volume due to the Mg2+ and Ca2+ bridging that formed spaces between the graphene sheets framework. Adsorption kinetics and the equilibrium adsorption isotherm were fitted by a pseudo-second-order alongside intraparticle diffusion kinetic models and Langmuir isotherm respectively. In addition, the divalent ion intercalated reduced graphene hydrogel showed good generation after three cycles of simultaneous adsorption.

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Synthesis, Characterization, and Adsorptive Properties of Fe3O4/GO Nanocomposites for Antimony Removal

Journal of Analytical Methods in Chemistry ◽

10.1155/2017/3012364 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Xiuzhen Yang ◽

Tengzhi Zhou ◽

Bozhi Ren ◽

Zhou Shi ◽

Andrew Hursthouse

Keyword(s):

Photoelectron Spectroscopy ◽

Adsorption Process ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Number Of Factors ◽

Infrared Spectrometer ◽

Pseudo Second Order ◽

Ft Ir ◽

Solid Liquid ◽

Solid Liquid Separation

A magnetic Fe3O4/GO composite with potential for rapid solid-liquid separation through a magnetic field was synthesized using GO (graphene oxide) and Fe3O4 (ferriferous oxide). Characterization of Fe3O4/GO used scanning electron microscope (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR), and Vibrating Sample Magnetometer (VSM). A number of factors such as pH and coexisting ions on adsorbent dose were tested in a series of batch experiments. The results showed that GO and Fe3O4 are strongly integrated. For pH values in the range of 3.0~9.0, the removal efficiency of Sb(III) using the synthesized Fe3O4/GO remained high (95%). The adsorption showed good fit to a pseudo-second-order and Langmiur model, with the maximum adsorption capacity of 9.59 mg/g maintained across pH 3.0–9.0. Thermodynamic parameters revealed that the adsorption process was spontaneous and endothermic. Analysis by X-ray photoelectron spectroscopy (XPS) showed that the adsorption process is accompanied by a redox reaction.

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Facile Production of a Fenton-Like Photocatalyst by Two-Step Calcination with a Broad pH Adaptability

Nanomaterials ◽

10.3390/nano10040676 ◽

2020 ◽

Vol 10 (4) ◽

pp. 676

Author(s):

Siyang Ji ◽

Yanling Yang ◽

Xing Li ◽

Hang Liu ◽

Zhiwei Zhou

Keyword(s):

Rhodamine B ◽

Photoelectron Spectroscopy ◽

Active Oxygen Species ◽

Oxygen Species ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Wide Ph Range ◽

Calcination Method ◽

Ph Range

A novel heterogeneous Fenton-like photocatalyst, Fe-doped graphitic carbon nitride (Fe-g-C3N4), was produced by facile two-step calcination method. This Fe–g–C3N4 catalyzed rhodamine B degradation in the presence of H2O2 accompanied with visible light irradiation. transmission electron microscopy(TEM), x-ray diffraction (XRD), FT-IR, x-ray photoelectron spectroscopy (XPS), and photoluminescence fluorescent spectrometer (PL) characterization analysis methods were adopted to evaluate the physicochemical property of samples. It can be observed that the Fe-g-C3N4 exhibited excellent photocatalytic Fenton-like activity at a wide pH range of 3–9, with rhodamine B(RhB) degradation efficiency up to 95.5% after irradiation for 45 min in the presence of 1.0 mM H2O2. Its high activity was ascribed to the formation of Fe–N ligands in the triazine rings that accelerated electron movement driving the Fe(III)/Fe(II) redox cycle, and inhibited photo-generated electron hole re-combinations for continuous generation of reactive oxygen species by reactions between Fe(II) and H2O2. The main active oxygen species were hydroxyl radicals, followed by superoxide radicals and hole electrons. This produced catalyst of Fe–g–C3N4 shows excellent reusability and stability, and can be a promising candidate for decontamination of wastewater.

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Diatomite modified by TiO2 for adsorption of U(VI)

Radiochimica Acta ◽

10.1515/ract-2018-2923 ◽

2018 ◽

Vol 106 (9) ◽

pp. 733-742 ◽

Cited By ~ 2

Author(s):

Ni Yuan ◽

Peng Liu ◽

Wangsuo Wu

Keyword(s):

Photoelectron Spectroscopy ◽

Sol Gel ◽

Water Environment ◽

X Ray ◽

Ph Values ◽

Batch Technique ◽

Adsorption Processes ◽

Novel Material ◽

Pseudo Second Order ◽

Synthesized Materials

Abstract Diatomite was modified with TiO2. The synthesized materials were characterized and used for removal of U(VI) from aqueous solutions. The influences of pH, contact time and temperature on U(VI) adsorption onto TiO2@diatomite were studied by batch technique, and X-ray photoelectron spectroscopy (XPS) was employed to analyze the experimental data. We compared the adsorption of U(VI) onto natural diatomite, TiO2 and TiO2@diatomite made by sol-gel method. The dynamic process showed that the adsorption of U(VI) onto TiO2@diatomite matched the pseudo-second-order kinetics model, and the adsorption of U(VI) was significantly dependent on pH values. Through simulating the adsorption isotherms by Langmuir, Freundlich and Dubini–Radushkevich (D–R) models, respectively, it could be seen that the adsorption patterns of U(VI) onto TiO2@diatomite were mainly controlled by surface complexation, and the adsorption processes were endothermic and spontaneous. The modification of diatomite by TiO2 shows a novel material for removing U(VI) from water environment for industrialized application.

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Preparation of KOH and H3PO4 Modified Biochar and Its Application in Methylene Blue Removal from Aqueous Solution

Processes ◽

10.3390/pr7120891 ◽

2019 ◽

Vol 7 (12) ◽

pp. 891 ◽

Cited By ~ 4

Author(s):

Li Liu ◽

Yang Li ◽

Shisuo Fan

Keyword(s):

Methylene Blue ◽

Photoelectron Spectroscopy ◽

Textile Wastewater ◽

Physical Interaction ◽

Order Kinetic ◽

X Ray Diffraction ◽

X Ray ◽

Modified Biochar ◽

Quality Of Water ◽

Pseudo Second Order

Improperly treated or directly discharged into the environment, wastewater containing dyes can destroy the quality of water bodies and pollute the ecological environment. The removal of dye wastewater is urgent and essential. In this study, corn stalk was pyrolyzed to pristine biochar (CSBC) in a limited oxygen atmosphere and modified using KOH and H3PO4 (KOH-CSBC, H3PO4-CSBC, respectively). The biochars were characterized by surface area and pore size, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), as well as their behavior in adsorbing methylene blue (MB). Results indicated that the pore structure of CSBC became more developed after modification by KOH. Meanwhile, H3PO4-CSBC contained more functional groups after activation treatment. The pseudo-second-order kinetic and the Langmuir adsorption isotherm represented the adsorption process well. The maximum MB adsorption capacity of CSBC, KOH-CSBC, and H3PO4-CSBC was 43.14 mg g−1, 406.43 mg g−1 and 230.39 mg g−1, respectively. Chemical modification significantly enhanced the adsorption of MB onto biochar, especially for KOH-CSBC. The adsorption mechanism between MB and biochar involved physical interaction, electrostatic interaction, hydrogen bonding and π–π interaction. Hence, modified CSBC (especially KOH-CSBC) has the potential for use as an adsorbent to remove dye from textile wastewater.

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Reduction of antimony by nano-particulate magnetite and mackinawite

Mineralogical Magazine ◽

10.1180/minmag.2008.072.1.185 ◽

2008 ◽

Vol 72 (1) ◽

pp. 185-189 ◽

Cited By ~ 44

Author(s):

R. Kirsch ◽

A. C. Scheinost ◽

A. Rossberg ◽

D. Banerjee ◽

L. Charlet

Keyword(s):

Oxidation State ◽

Photoelectron Spectroscopy ◽

Redox Processes ◽

Environmental Behaviour ◽

X Ray ◽

Ph Values ◽

Wide Ph Range ◽

Ph Range ◽

X Ray Absorption

AbstractThe speciation of antimony is strongly influenced by its oxidation state (V, III, 0, —III). Redox processes under anaerobic groundwater conditions may therefore greatly alter the environmental behaviour of Sb. Employing X-ray absorption and photoelectron spectroscopy, we show here that Sb(V) is reduced to Sb(III) by magnetite and mackinawite, two ubiquitous Fe(II)-containing minerals, while Sb(III) is not reduced further. At the surface of magnetite, Sb(III) forms a highly symmetrical sorption complex at the position otherwise occupied by tetrahedral Fe(III). The Sb(V) reduction increases with pH, and at pH values >6.5 Sb(V) is completely reduced to Sb(III) within 30 days. In contrast, at the mackinawite surface, Sb(V) is completely reduced across a wide pH range and within 1 h. The Sb(V) reduction proceeds solely by oxidation of surface Fe(II), while the oxidation state of sulphide is conserved. Independent of whether Sb(V) or Sb(III) was added, an amorphous or nano-particulate SbS3-like solid formed.

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A Mechanism for the Adsorption of 2-(Hexadecanoylamino)Acetic Acid by Smithsonite: Surface Spectroscopy and Microflotation Experiments

Minerals ◽

10.3390/min9010015 ◽

2018 ◽

Vol 9 (1) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

Bin Luo ◽

Junbo Liu ◽

Quanjun Liu ◽

Chao Song ◽

Li Yu ◽

...

Keyword(s):

Acetic Acid ◽

Zeta Potential ◽

Photoelectron Spectroscopy ◽

Sulfide Mineral ◽

X Ray ◽

Surface Spectroscopy ◽

Wide Ph Range ◽

Flotation Performance ◽

Ph Range ◽

Important Objective

Zinc is mostly extracted from oxidized zinc and zinc sulfide minerals, and this process involves flotation as a key step. While it is easier to float the sulfide mineral, its consumption and depletion has led to an increased reliance on oxidized zinc minerals, including smithsonite. Hence, the development of efficient ways of collecting smithsonite by flotation is an important objective. Herein, we describe the use of 2-(hexadecanoylamino)acetic acid (HAA), a novel surfactant, as a collector during smithsonite flotation. The mechanism and flotation performance of HAA during smithsonite flotation was investigated by total organic carbon (TOC) content studies, zeta potential measurements, Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) analyses, combined with microflotation experiments. The flotation results revealed that HAA was an excellent collector in pulp over a wide pH range (9–12) and at a relatively low concentration (2 × 10−4 mol/L), at which a recovery of close to 90% of the smithsonite mineral was obtained. TOC content studies revealed that the good flotation recovery was ascribable to large amounts of collector molecule adsorbed on the smithsonite surface, while zeta potential measurements showed that the HAA was chemically adsorbed onto the smithsonite. FTIR and XPS analyses revealed that the HAA collector molecules adsorbed onto the smithsonite surface as zinc–HAA complexes involving carboxylate moieties and Zn sites on the smithsonite surface in alkaline solution.

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Kinetics and isotherm modeling of Pb(II) and Cd(II) sequestration from polluted water onto tropical ultisol obtained from Enugu Nigeria

Applied Water Science ◽

10.1007/s13201-021-01402-8 ◽

2021 ◽

Vol 11 (4) ◽

Author(s):

Theresa C. Umeh ◽

John K. Nduka ◽

Kovo G. Akpomie

Keyword(s):

Metal Ions ◽

Low Cost ◽

Water Environment ◽

Standard Technique ◽

Soil Surface ◽

Cost Effective ◽

Polluted Water ◽

Batch Adsorption ◽

Lead And Cadmium ◽

Pseudo Second Order

AbstractDeterioration in soil–water environment severely contributed by heavy metal bioavailability and mobility on soil surface and sub-surface due to irrational increase in wastewater discharge and agrochemical activities. Therefore, the feasibility of adsorption characteristics of the soil is paramount in curbing the problem of micropollutant contamination in the farming vicinity. Soil from a farming site in a populated area in Enugu, Nigeria was collected and tested to measure the lead and cadmium contents using atomic absorption spectrophotometer (AAS). The adsorption potency of the ultisol soil was estimated for identifiable physicochemical properties by standard technique. The mean activity concentration of Pb2+ and Cd2+ was 15.68 mg/kg and 3.01 mg/kg. The pH, temperature, metal concentration and contact time adsorptive effect on the Pb2+ and Cd2+ uptake was evaluated by batch adsorption technique. The Langmuir, Freundlich and Temkin models were fitted into equilibrium adsorption data and the calculated results depict a better and satisfactory correlation for Langmuir with higher linear regression coefficients (Pb2+, 0.935 and Cd2+, 0.971). On the basis of sorption capacity mechanism of the soil, pseudo-second-order model best described the kinetics of both metal ions retention process. The results of the present study indicated that the soil being a low cost-effective adsorbent can be utilized to minimize the environmental risk impact of these metal ions.

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