β-Cyclodextrin Modified Poly(Acrylonitrule-co-Acrylic Acid) Hydrogel for Thorium(IV) Adsorption

In this report, the β-CD(AN-co-AA) hydrogel was used to remove the thorium(IV) [Th(IV)] from the water system, and the new adsorbent was characterized through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The influences of contact time, pH value, ionic strength, solid-liquid ratio, initial Th(IV) concentration, and temperature on Th(IV) adsorption onto the functional hydrogel were researched. The results showed that the experimental data followed the Langmuir isotherm and the maximum adsorption capacity (qmax) for Th(IV) was 692 mg/g at pH 2.95, which approached the calculated (qe) 682 mg/g. The desorption capacity of Th(IV) in different HNO3 concentrations ranging from 0.005 to 0.5 M was also studied, and the percentage of the maximum desorption was 86.85% in the condition of 0.09 M HNO3. The selectivity of β-CD(AN-co-AA) hydrogel was also be studied, the results indicated that this material retained the good adsorption capacity to Th(IV) even when the Ca2+, Mg2+, or Pb2+ existed in the system. The findings indicate that β-CD(AN-co-AA) can be used as a new candidate for the enrichment and separation of Th(IV), or its analogue actinides, from large-volume solution in practical application.

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Preparation and Characterization of the Sulfur-Impregnated Natural Zeolite Clinoptilolite for Hg(II) Removal from Aqueous Solutions

Processes ◽

10.3390/pr9020217 ◽

2021 ◽

Vol 9 (2) ◽

pp. 217

Author(s):

Marin Ugrina ◽

Martin Gaberšek ◽

Aleksandra Daković ◽

Ivona Nuić

Keyword(s):

Chemical Modification ◽

Aqueous Solutions ◽

Specific Surface ◽

Surface Area ◽

Natural Zeolite ◽

Contact Time ◽

Liquid Ratio ◽

X Ray ◽

Solid Liquid

Sulfur-impregnated zeolite has been obtained from the natural zeolite clinoptilolite by chemical modification with Na2S at 150 °C. The purpose of zeolite impregnation was to enhance the sorption of Hg(II) from aqueous solutions. Chemical analysis, acid and basic properties determined by Bohem’s method, chemical behavior at different pHo values, zeta potential, cation-exchange capacity (CEC), specific surface area, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), as well as thermogravimetry with derivative thermogravimetry (TG-DTG) were used for detailed comparative mineralogical and physico-chemical characterization of natural and sulfur-impregnated zeolites. Results revealed that the surface of the natural zeolite was successfully impregnated with sulfur species in the form of FeS and CaS. Chemical modification caused an increase in basicity and the net negative surface charge due to an increase in oxygen-containing functional groups as well as a decrease in specific surface area and crystallinity due to the formation of sulfur-containing clusters at the zeolite surface. The sorption of Hg(II) species onto the sulfur-impregnated zeolite was affected by the pH, solid/liquid ratio, initial Hg(II) concentration, and contact time. The optimal sorption conditions were determined as pH 2, a solid/liquid ratio of 10 g/L, and a contact time of 800 min. The maximum obtained sorption capacity of the sulfur-impregnated zeolite toward Hg(II) was 1.02 mmol/g. The sorption mechanism of Hg(II) onto the sulfur-impregnated zeolite involves electrostatic attraction, ion exchange, and surface complexation, accompanied by co-precipitation of Hg(II) in the form of HgS. It was found that sulfur-impregnation enhanced the sorption of Hg(II) by 3.6 times compared to the natural zeolite. The leaching test indicated the retention of Hg(II) in the zeolite structure over a wide pH range, making this sulfur-impregnated sorbent a promising material for the remediation of a mercury-polluted environment.

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Adsorción del naranja de metilo en solución acuosa sobre hidróxidos dobles laminares

Acta Universitaria ◽

10.15174/au.2015.778 ◽

2015 ◽

Vol 25 (3) ◽

pp. 25-34 ◽

Cited By ~ 2

Author(s):

Laura Alicia Ramírez Llamas ◽

Araceli Jacobo Azuara ◽

J. Merced Martínez Rosales

Keyword(s):

Methyl Orange ◽

Adsorption Capacity ◽

Dye Adsorption ◽

Temperature Programmed Desorption ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

Suitable Temperature ◽

Temperature Programmed ◽

Double Hydroxides

In this paper, layered double hydroxides (LDH) were synthesized and characterized using techniques of Physisorption of Nitrogen, Infrared, Temperature Programmed Desorption, X-Ray Diffraction, TGA and Immersion Microcalorimetry, in order to determine the basic properties of the adsorbent. The methyl orange (MO) is used as a dye and as a result, it is frequently found in effluents from textile industries. The dye adsorption isotherms on LDH were studied as function of pH and temperature. The maximum adsorption capacity of methyl orange on LDH was carried out at pH 5, and the minimum adsorption capacity at pH 11, being 40.2 mg/g and 22.1 mg/g, respectively. Furthermore, the suitable temperature to promote the adsorption of methyl orange on LDH was at 25 °C, as at 35 °C shows a significant decrease.

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Wet-Purification of a Sodium-Based Bentonite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.743-744.692 ◽

2013 ◽

Vol 743-744 ◽

pp. 692-696

Author(s):

Shui Lin Zheng ◽

Yang Yang Huai ◽

Zhen Wei Li ◽

Hao Ran Cui ◽

Zhi Ming Sun

Keyword(s):

Methylene Blue ◽

Diffraction Analysis ◽

Purification Process ◽

X Ray Diffraction ◽

Liquid Ratio ◽

X Ray ◽

Solid Liquid

Bentonite mainly consists of montmorillonite, but is always associated with other impure minerals. In order to increase the montmorillonite content in raw bentonite from Xinjiang, this paper adopts wet-purification process which integrates the scrubbing process with streamlined centrifugalization. The optimum experiment condition is solid - liquid ratio (wv) 130, macerating time 20h, scrubbing time 10min, centrifugation time 13min, centrifugation velocity 1260r/min, ZHL dosage 0.4% and ZHC dosage 0.4%. According to the amount of methylene blue absorption raising from 64.5mmol/100g to 110mmol/100g and X-ray diffraction analysis, the montmorillonite content raises from 48% to 82%.

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Preparation of GO/MIL-101(Fe,Cu) composite and its adsorption mechanisms for phosphate in aqueous solution

10.21203/rs.3.rs-191207/v1 ◽

2021 ◽

Author(s):

You Wu ◽

Zuannian Liu ◽

Bakhtari Mohammad Fahim ◽

Junnan Luo

Keyword(s):

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Adsorption Mechanism ◽

Nitrogen Adsorption ◽

Adsorption Properties ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

Adsorption Mechanisms ◽

Adsorption Desorption

Abstract In this study, MIL-101(Fe), MIL-101(Fe,Cu), and Graphene Oxide (GO) /MIL-101(Fe,Cu) were synthesized to compose a novel sorbent. The adsorption properties of these three MOFs-based composites were compared toward the removal of phosphate. Furthermore, the influencing factors including reaction time, pH, temperature and initial concentration on the adsorption capacity of phosphate on these materials as well as the reusability of the material were discussed. The structure of fabricated materials and the removal mechanism of phosphate on the composite material were analyzed by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption analysis and zeta potential. The results show that the maximum adsorption capacity of phosphate by the composite GO/MIL-101(Fe,Cu)-2% was 204.60 mg·g− 1, which is higher than that of MIL-101(Fe,Cu) and MIL-101(Fe). likewise the specific surface area of GO/MIL-101(Fe,Cu)-2% is 778.11 m2/g is higher than that of MIL-101(Fe,Cu) and MIL-101(Fe),which are 747.75 and 510.66m2/g respectively. The adsorption mechanism of phosphate is electrostatic attraction, form coordination bonds and hydrogen bonds. The fabricated material is a promising adsorbent for the removal of phosphate with good reusability.

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Removal of Copper from Vineyard Soil by Washing with Biosurfactant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1065-1069.3091 ◽

2014 ◽

Vol 1065-1069 ◽

pp. 3091-3095

Author(s):

Da Zhao ◽

Yue Zhao ◽

Shi Bo Tao

Keyword(s):

Removal Efficiency ◽

Contact Time ◽

Ph Value ◽

Batch Experiments ◽

Liquid Ratio ◽

Washing Process ◽

Vineyard Soil ◽

Alkaline Conditions ◽

Solid Liquid ◽

Fermentation Solution

The washing process in batch experiments was conducted to investigate the performance of fermentation solution on removal copper(Cu) from vineyard soil. The effects of solid-liquid ratio, pH value and contact time on the removal capacities of Cu by fermentation solution had been studied. The results showed that the optimum solid-liquid ratio was 1:10 for soil treatment. The fermentation solution showed a better removal efficiency of Cu in alkaline conditions, getting the highest removal efficiency of 34.3%. In addition, with the increase of contact time, higher removal efficiency was obtained.

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Fe(III) Complexed Polydopamine Modified Mg/Al Layered Double Hydroxide Enhances The Removal of Cr(VI) From Aqueous Solutions

10.21203/rs.3.rs-854606/v1 ◽

2021 ◽

Author(s):

Changcheng Chen ◽

Mina Luo ◽

Fu Chen ◽

Chao Huang ◽

Chunmei Zhu ◽

...

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

Adsorption Mechanisms ◽

Removal Capacity ◽

Double Hydroxide ◽

Double Hydroxides ◽

Influence Of Ph

Abstract Herein, we report the preparation of Fe(III) complexed polydopamine modified Mg/Al layered double hydroxides composite material (LDHs@PDA-Fe(III)) and its application to the removal of Cr(VI) in aqueous solution. LDHs@PDA-Fe(III) was characterized and analyzed by field-emission scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transformed infrared (FTIR), X-ray diffraction (XRD), X-ray photoelectron (XPS). The adsorption performance was studied through a series of adsorption experiments. Under the influence of pH, time, temperature, concentration, the maximum adsorption capacity obtained in the experiment is 683.4 mg/g. In addition, after 5 adsorption cycles, LDHs@PDA-Fe(III) still shows excellent adsorption capacity and stability. Combining adsorption experiments and characterization analysis, it is inferred that the adsorption of Cr(VI) by LDHs@PDA-Fe(III) is the result of the synergistic effect of multiple adsorption mechanisms. Therefore, the efficient removal capacity and excellent stability make LDHs@PDA-Fe(III) an ideal adsorbent for removing Cr(VI) from aqueous solutions.

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Removal of Phosphorus from Wastewater by Different Morphological Alumina

Molecules ◽

10.3390/molecules25133092 ◽

2020 ◽

Vol 25 (13) ◽

pp. 3092

Author(s):

Jianchuan Sun ◽

Awang Gao ◽

Xuhui Wang ◽

Xiangyu Xu ◽

Jiaqing Song

Keyword(s):

Adsorption Capacity ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

Phosphorus Adsorption ◽

X Ray ◽

Transmission Electron ◽

Ft Ir ◽

Series Of Experiments ◽

Level 1 ◽

Adsorption Desorption

In this work, an organic-free method was used to synthesize different morphological boehmite by controlling the crystallization temperature, and alumina adsorbents were obtained by baking the boehmites at 500 °C. The alumina adsorbents were characterized by X-ray diffraction (XRD), High resolution transmission electron microscope (HRTEM), Fourier transform infrared (FT-IR), N2 adsorption/desorption analysis, and their phosphorus adsorption properties were comparatively investigated by a series of experiments. The results showed that the self-prepared alumina adsorbents were lamellar and fibrous material, while the industrial adsorbent was a granular material. The lamellar alumina adsorbents had the largest specific surface area and showed better phosphorus adsorption capacity. The maximum adsorption capacity could reach up to 588.2 mg·g−1; and only 0.8 g·L−1 of lamellar alumina adsorbent is needed to treat 100 mg·L−1 phosphorus solution under the Chinese level 1 discharge standard (0.5 mg·L−1). Further investigation suggests that the lamellar alumina adsorbent kept high adsorption capacity in various solution environments.

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Adsorption Characteristic of U(VI) on Fe-Immobilized Bentonite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.639-640.1300 ◽

2013 ◽

Vol 639-640 ◽

pp. 1300-1306

Author(s):

Zhen Ping Tang ◽

Hui Ling ◽

Shui Bo Xie ◽

S.Y. Li ◽

J.S. Wang ◽

...

Keyword(s):

Adsorption Capacity ◽

Adsorption Mechanism ◽

Ph Value ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

X Ray Diffraction ◽

Solution Ph ◽

Adsorption Characteristic ◽

Order Kinetic Equation

Fe-immobilized bentonite, prepared with bentonite and FeCl3 was used for the adsorption of uranium(VI) in this study, solution pH, ion strength, contact time and temperature were investigated, structural characterization of Fe-immobilized bentonite was assayed by X-ray Diffraction and Fourier Transform Infrared Spectroscopy. Results indicated that the adsorption capacity were strongly affected by the solution pH and ion strength, the adsorption efficiency was 91.8% when pH value was 6 and ion strength was 0.01 mol•L-1, higher or lower pH did not favor the U(VI) adsorption. The adsorption mechanism was discussed by the views of reactive kinetics and thermodynamics along with Scanning Electron Microscope. The adsorption kinetics process was fitted well with the second-order kinetic equation, when the initial U(VI) concentration was less than 38.08mg/L, Langmuir equations could describe the adsorption isotherm of U(VI) well with the maximum adsorption capacity of 169.5mg/g at 303K

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Effects of TETA or TEPA Loading on CO2 Adsorption Properties Using Pore-Expanded KIT-6 as Support

NANO ◽

10.1142/s179329201850042x ◽

2018 ◽

Vol 13 (04) ◽

pp. 1850042 ◽

Cited By ~ 3

Author(s):

Jianwen Wei ◽

Dejun Mei ◽

Zhifeng Lin ◽

Linlin Geng ◽

Siqi Chen ◽

...

Keyword(s):

Adsorption Capacity ◽

Maximum Adsorption Capacity ◽

Gravimetric Analysis ◽

Impregnation Method ◽

X Ray Diffraction ◽

Structure Directing Agent ◽

X Ray ◽

Silica Source ◽

Adsorption Capacities ◽

Adsorption Desorption

Mesoporous silica pore-expanded KIT-6 was synthesized using tetraethoxysilane (TEOS) as the silica source, tri-block copolymer (P123) as a structure-directing agent and 1,3,5-trimethylbenzene (TMB) as swelling agents by a hydrothermal method. Then, pore-expanded KIT-6 (PE-KIT-6) was modified with different amounts of amines including triethylenetetramine (TETA) and tetraethylenepentamine (TEPA) by a post-synthetic impregnation method. The samples were characterized by small-angle X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2 adsorption/desorption, elemental analysis and thermal gravimetric analysis (TGA). Experimental results revealed that the modifiers were introduced into the samples and the CO2 adsorption capacity increased first and then decreased with the increase of TETA/TEPA loadings. Under the same loadings of TETA/TEPA, the samples modified by TEPA exhibited better CO2 adsorption capacities than the samples modified by TETA because TEPA has one more amine group than TETA in the molecule. The results also indicated that the samples had good adsorption capacities at the loadings ranging from 30% to 35%. Among them, the sample modified by TEPA with the loading of 35% had the maximum adsorption capacity of 2.9[Formula: see text]mmol/g. After five cycles of adsorption/desorption, the adsorption capacity only dropped 4.59%, indicating that the adsorbent of PE-KIT-6 modified by TEPA has good cyclic stability.

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Synthesis of a Novel Ce-bpdc for the Effective Removal of Fluoride from Aqueous Solution

Advances in Condensed Matter Physics ◽

10.1155/2017/8305765 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Changqing Zhao ◽

Yanwei Cui ◽

Fang Fang ◽

Si Ok Ryu ◽

Jiarui Huang

Keyword(s):

Adsorption Capacity ◽

Removal Efficiency ◽

Photoelectron Spectroscopy ◽

Ph Value ◽

Binding Capacity ◽

Fluoride Removal ◽

Maximum Adsorption Capacity ◽

Fluoride Ions ◽

X Ray ◽

Fluoride Adsorption

Ce-1,1′-biphenyl-4,4′-dicarboxylic acid (Ce-bpdc), a novel type of metal organic framework, was synthesized and applied to remove excessive fluoride from water. The structure and morphology of Ce-bpdc were measured by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The effects, such as saturated adsorption capacity, HCO3-, and pH, were investigated. The optimal pH value for fluoride adsorption was the range from 5 to 6. The coexisting bicarbonate anions have a little influence on fluoride removal. The fluoride adsorption over the Ce-bpdc adsorbent could reach its equilibrium in about 20 min. The Ce-bpdc coordination complex exhibited high binding capacity for fluoride ions. The maximum adsorption capacity calculated from Langmuir model was high up to 45.5 mg/g at 298 K (pH = 7.0) and the removal efficiency was greater than 80%. In order to investigate the mechanism of fluoride removal, various adsorption isotherms such as Langmuir and Freundlich were fitted. The experimental data revealed that the Langmuir isotherm gave a more satisfactory fit for fluoride removal. Finally, the tested results of ground water samples from three places, Yuefang, Jiangji, and Sanyi which exhibited high removal efficiency, also demonstrate the potential utility of the Ce-bpdc as an effective adsorbent.

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