Recovery of phosphate from aqueous solution by magnetically recycled modified polishing powder composites

Abstract This study investigated a magnetically recycled modified polishing powder (CMIO@PP) as an adsorbent of phosphate; the CMIO@PP was synthesized by combining the modified La/Ce-containing waste polishing powder with CaO2-modified Fe3O4 (CMIO). Results indicate that the CMIO@PP nanocomposite presents a crystal structure comprising La (OH)3, Ce (OH)3, and Fe3O4, and that CMIO is uniformly dispersed in the modified polishing powder. The CMIO@PP (1:3) is a suitable choice considering its magnetism and adsorption capacity. The magnetic adsorbent exhibits a high adsorption capacity of 53.72 mg/g, a short equilibrium time of 60 min, and superior selectivity for phosphate. Moreover, the adsorbent strongly depends on the pH during the adsorption process and maintains a large adsorption capacity when the pH level is between 2 and 6. The adsorption of phosphate by the CMIO@PP (1:3) accords with the Langmuir isotherm model, and the adsorption process follows the pseudo-second order model. Meanwhile, adsorption–desorption experiments show that the adsorbent could be recycled a few times and that a high removal efficiency of phosphate from civil wastewater was achieved. Finally, mechanisms show that the adsorption of phosphate by the CMIO@PP (1:3) is mainly caused by electrostatic attraction and ligand exchange.

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Adsorptive removal of Rhodamine B from aqueous solution by nanoporous polydivinylbenzene

Water Science & Technology ◽

10.2166/wst.2017.029 ◽

2017 ◽

Vol 75 (7) ◽

pp. 1651-1658 ◽

Cited By ~ 4

Author(s):

Hongyu Jia ◽

Ningning Liu

Keyword(s):

Rhodamine B ◽

Adsorption Process ◽

Order Model ◽

N2 Adsorption ◽

Adsorptive Removal ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Desorption Isotherms ◽

Adsorption Desorption ◽

Scanning Electron

Nanoporous polydivinylbenzene (PDVB) material has been successfully prepared via the copolymerization of divinylbenzene monomers. The nanoporous PDVB was characterized through N2 adsorption/desorption isotherms, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The nanoporous PDVB as an adsorbent was applied for the removal of Rhodamine B (RhB). The adsorption behavior of PDVB for the removal of RhB showed that the isotherm data followed the Langmuir isotherm model and the kinetic adsorption obeyed the pseudo-second-order model. Thermodynamic parameters illustrated that the adsorption process was spontaneous and exothermic. Interestingly, the spent nanoporous PDVB has excellent regenerative performance through treating it with ethanol. These results revealed that PDVB might be an excellent adsorbent for the removal of RhB from wastewater.

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RGO/CNF/PANI AS AN EFFECTIVE ADSORBENT FOR THE ADSORPTION OF URANIUM FROM AQUEOUS SOLUTION

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/56/1a/12500 ◽

2018 ◽

Vol 56 (1A) ◽

pp. 25

Author(s):

Nguyen Quang Dat

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Adsorption Process ◽

Uranium Concentration ◽

Maximum Adsorption Capacity ◽

High Adsorption ◽

Order Model ◽

Pani Composite ◽

Reduced Graphene ◽

Pseudo Second Order

In this paper, we present a recent study in the adsorption of uranium from an aquatic environment by reduced graphene oxide - Cu0.5Ni0.5Fe2O4 ferrite – polyaniline (RGO/CNF/PANI) composite. Uranium concentration was carried out by batch techniques. The effect of pH, contact time, concentration of equilibrium state and reusability on uranium adsorption capacity have been studied. The adsorption process was accomplished within 240 min and could be well described by the pseudo-second-order model. The adsorption isotherm agrees well with the Langmuir model, having a maximum adsorption capacity of 2000 mg/g, at pH = 5 and 25 oC. The RGO/CNF/PANI materials could be a promising absorbent for removing U (VI) in aqueous solution because of their high adsorption capacity and convenient magnetic separation.

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Adsorption of strontium on different sodium-enriched bentonites

Journal of the Serbian Chemical Society ◽

10.2298/jsc161010008m ◽

2017 ◽

Vol 82 (4) ◽

pp. 449-463 ◽

Cited By ~ 6

Author(s):

Sanja Marinovic ◽

Marija Ajdukovic ◽

Natasa Jovic-Jovicic ◽

Tihana Mudrinic ◽

Bojana Nedic-Vasiljevic ◽

...

Keyword(s):

Cation Exchange ◽

Adsorption Capacity ◽

Textural Properties ◽

X Ray Diffraction ◽

Order Model ◽

Surface Areas ◽

Alkaline Conditions ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Ph Range

Bentonites from three different deposits (Wyoming, TX, USA and Bogovina, Serbia) with similar cation exchange capacities were sodium enriched and tested as adsorbents for Sr2+ in aqueous solutions. X-Ray diffraction analysis confirmed successful Na-exchange. The textural properties of the bentonite samples were determined using low-temperature the nitrogen physisorption method. Significant differences in the textural properties between the different sodium enriched bentonites were found. Adsorption was investigated with respect to adsorbent dosage, pH, contact time and the initial concentration of Sr2+. The adsorption capacity increased with pH. In the pH range from 4.0?8.5, the amount of adsorbed Sr2+ was almost constant but 2?3 times smaller than at pH ?11. Further experiments were performed at the unadjusted pH since extreme alkaline conditions are environmentally hostile and inapplicable in real systems. The adsorption capacity of all the investigated adsorbents toward Sr2+ was similar under the investigated conditions, regardless of significant differences in the specific surface areas. It was shown and confirmed by the Dubinin?Radushkevich model that the cation exchange mechanism was the dominant mechanism of Sr2+ adsorption. Their developed microporous structures contributed to the Sr2+ adsorption process. The adsorption kinetics obeyed the pseudo-second-order model. The isotherm data were best fitted with the Langmuir isotherm model.

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Equilibrium and Kinetic Study of Lead and Copper Ion Adsorption on Chitosan-Grafted-Polyacrylic Acid Synthesized by Surface Initiated Atomic Transfer Polymerization

Molecules ◽

10.3390/molecules23092218 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2218 ◽

Cited By ~ 6

Author(s):

Carlos Grande-Tovar ◽

William Vallejo ◽

Fabio Zuluaga

Keyword(s):

Adsorption Capacity ◽

Polyacrylic Acid ◽

Adsorption Process ◽

Kinetic Constant ◽

Copper Ion ◽

Toxic Metal ◽

Maximum Adsorption Capacity ◽

Order Model ◽

Equilibrium Studies ◽

Pseudo Second Order

In this work, we synthesized chitosan grafted-polyacrylic acid (CS-g-PA) through surface-initiated atom transfer radical polymerization (SI-ATRP). We also studied the adsorption process of copper and lead ions onto the CS-g-PA surface. Adsorption equilibrium studies indicated that pH 4.0 was the best pH for the adsorption process and the maximum adsorption capacity over CS-g-PA for Pb2+ ions was 98 mg·g−1 and for Cu2+ it was 164 mg·g−1, while for chitosan alone (CS), the Pb2+ adsorption capacity was only 14.8 mg·g−1 and for Cu2+ it was 140 mg·g−1. Furthermore, the adsorption studies indicated that Langmuir model describes all the experimental data and besides, pseudo-second-order model was suitable to describe kinetic results for the adsorption process, demonstrating a larger kinetic constant of the process was larger for Pb2+ than Cu2+. Compared to other adsorbents reported, CS-g-PA had comparable or even superior adsorbent capacity and besides, all these results suggest that the new CS-g-PA polymers had potential as an adsorbent for hazardous and toxic metal ions produced by different industries.

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High Removal Efficiency of Diatomite-Based X Zeolite for Cu2+ and Zn2+

Materials ◽

10.3390/ma14216525 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6525

Author(s):

Guangyuan Yao ◽

Yuqiang Liu ◽

Shuilin Zheng ◽

Ya Xu

Keyword(s):

Ion Exchange ◽

Adsorption Process ◽

Interface Properties ◽

Order Model ◽

Adsorption Capacities ◽

Adsorption Data ◽

X Zeolite ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Kinetics And Isotherms

Diatomite-based X zeolite was obtained and its crystallinity, morphology, and interface properties were investigated by XRD, BET, SEM, EDS, and XRF. The obtained X zeolite possessed a unique meso-microporous structure and showed good ion exchange properties for Cu2+ and Zn2+. The pseudo-second-order model and Langmuir isotherm model can best describe the adsorption kinetics and isotherms of Cu2+ and Zn2+, respectively. The maximal adsorption capacities of X zeolite for Cu2+ and Zn2+ were 146 and 195 mg/g at 323 K, respectively. Meanwhile, the adsorption process for Cu2+ and Zn2+ were chemical adsorption and ion exchange, respectively. Furthermore, the adsorption data turned out to be an endothermic and spontaneous process. Compared with other reported materials, the adsorption capacity of X zeolite synthesized from diatomite was among the highest. Therefore, it could be a promising adsorbent for the disposal of wastewater that contains metal ions.

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Development of Pectin-Based Aerogels with Several Excellent Properties for the Adsorption of Pb2+

Foods ◽

10.3390/foods10123127 ◽

2021 ◽

Vol 10 (12) ◽

pp. 3127

Author(s):

Risi Wang ◽

Ya Li ◽

Xixiang Shuai ◽

Jun Chen ◽

Ruihong Liang ◽

...

Keyword(s):

Mechanical Strength ◽

Adsorption Capacity ◽

Functional Groups ◽

Adsorption Process ◽

Diglycidyl Ether ◽

Order Model ◽

High Mechanical Strength ◽

Adsorption Data ◽

Pseudo Second Order ◽

Large Maximum

Traditional aerogels lack specific functional groups for the adsorption of Pb2+, which results in a low adsorption capacity and limits the application scope. Novel porous pectin-based aerogels (PPEAs) were prepared by incorporating polyethylenimine (PEI) using ethylene glycol diglycidyl ether (EGDE) as a cross-linker for the removal of Pb2+ from water. The cross-linking mechanism, morphology, mechanical strength, thermal stability, adsorption properties, and mechanism of the aerogels were investigated. The aerogels possessed several desirable features, such as a large maximum Pb2+ adsorption capacity (373.7 mg/g, tested at pH 5.0), ultralight (as low as 63.4 mg/cm3), high mechanical strength (stress above 0.24 MPa at 50% strain), and easy recyclability. Meanwhile, the equilibrium adsorption data was well described by the Langmuir–Freundlich (Sips) model and the kinetic adsorption process was well fitted using the pseudo-second-order model. The donor groups, such as -NH2, and oxygen-containing functional groups were responsible for the Pb2+ adsorption, which was confirmed by the FTIR and XPS analysis. The excellent characteristics mean that PPEAs are highly effective adsorbents in the remediation of lead-containing wastewater.

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Preparation of hydrogel reinforced with bentonite by gamma irradiation for metal absorption

Nuclear Science and Technology ◽

10.53747/jnst.v10i4.15 ◽

2021 ◽

Vol 10 (4) ◽

pp. 48-55

Author(s):

Tran To Uyen ◽

Trinh Thi Tu Anh ◽

Tamikazu Kume ◽

Cao Dong Vu ◽

Nguyen Minh Hiep ◽

...

Keyword(s):

Gamma Irradiation ◽

Adsorption Process ◽

Absorption Spectrometry ◽

Order Model ◽

Adsorption Capacities ◽

Dose Concentration ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Aas Method ◽

Irradiation Technology

A natural-based sodium carboxymethyl cellulose (CMC) hydrogel reinforced with bentonite was prepared by using gamma irradiation technology. This is a novel hydrogel that uses natural polymer to absorb metal ions in wastewater. The influence of dose, concentration of CMC and bentonite on the sorption of hydrogels was investigated by atomic absorption spectrometry (AAS) method. According to the Langmuir isotherm model, the maximum adsorption capacities of CMC/bentonite hydrogel for Cu2+ and Pb2+ were 181.82 mg/g and 204.08 mg/g at room temperature, respectively. The pseudo-second-order model which describes the adsorption process of Cu2+ and Pb2+ was also studied

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Nascent Rice Husk as an Adsorbent for Removing Cationic Dyes from Textile Wastewater

Applied Sciences ◽

10.3390/app10103437 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3437

Author(s):

Jude Ofei Quansah ◽

Thandar Hlaing ◽

Fritz Ndumbe Lyonga ◽

Phyo Phyo Kyi ◽

Seung-Hee Hong ◽

...

Keyword(s):

Adsorption Capacity ◽

Rice Husk ◽

Textile Wastewater ◽

Cationic Dyes ◽

Adsorption Model ◽

Order Model ◽

Solution Ph ◽

Freundlich Model ◽

Langmuir Isotherm Model ◽

Pseudo Second Order

We assessed the applicability of rice husk (RH) to remove cationic dyes, i.e., methylene blue (MB) and crystal violet (CV), from water. RH thermally treated at 75 °C showed a higher adsorption capacity than that at high temperatures (300–700 °C). For a suitable CV-adsorption model, a pseudo-first-order model for MB adsorption was followed by the kinetics adsorption process; however, a pseudo-second-order model was then suggested. In the qt versus t1/2 plot, the MB line passed through the origin, but that of CV did not. The Langmuir isotherm model was better than the Freundlich model for both dye adsorptions; furthermore, the adsorption capacity for MB and CV was 24.48 mg/g and 25.46 mg/g, respectively. Thermodynamically, the adsorption of both MB and CV onto the RH was found to be spontaneous and endothermic. This adsorption increased insignificantly on increasing the solution pH from 4 to 10. With an increasing dosage of the RH, there was an increase in the removal percentages of MB and CV; however, adsorption capacity per unit mass of the RH was observed to decrease. Therefore, we conclude that utilizing RH as an available and affordable adsorbent is feasible to remove MB and CV from wastewater.

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Corn stalk as starting material to prepare a novel adsorbent via SET-LRP and its adsorption performance for Pb(II) and Cu(II)

Royal Society Open Science ◽

10.1098/rsos.191811 ◽

2020 ◽

Vol 7 (3) ◽

pp. 191811

Author(s):

Yazhen Wang ◽

Shuang Li ◽

Liqun Ma ◽

Shaobo Dong ◽

Li Liu

Keyword(s):

Adsorption Capacity ◽

Potassium Hydroxide ◽

Adsorption Process ◽

Hydroxylamine Hydrochloride ◽

Freundlich Isotherm ◽

Maximum Adsorption Capacity ◽

Corn Stalk ◽

Order Model ◽

Adsorption Performance ◽

Pseudo Second Order

Corn stalk was used as the initial material to prepare a corn stalk matrix-g-polyacrylonitrile-based adsorbent. At first, the corn stalk was treated with potassium hydroxide and nitric acid to obtain the corn stalk-based cellulose (CS), and then the CS was modified by 2-bromoisobutyrylbromide (2-BiBBr) to prepare a macroinitiator. After that, polyacrylonitrile (PAN) was grafted onto the macroinitiator by single-electron transfer living radical polymerization (SET-LRP). A novel adsorbent AO CS-g-PAN was, therefore, obtained by introducing amidoxime groups onto the CS-g-PAN with hydroxylamine hydrochloride (NH 2 OH · HCl). FTIR, SEM and XPS were applied to characterize the structure of AO CS-g-PAN. The adsorbent was then employed to remove Pb(II) and Cu(II), and it exhibited a predominant adsorption performance on Pb(II) and Cu(II). The effect of parameters, such as temperature, adsorption time, pH and the initial concentration of metal ions on adsorption capacity, were examined in detail during its application. Results suggest that the maximum adsorption capacity of Pb(II) and Cu(II) was 231.84 mg g –1 and 94.72 mg g −1 , and the corresponding removal efficiency was 72.03% and 63%, respectively. The pseudo-second order model was more suitable to depict the adsorption process. And the adsorption isotherm of Cu(II) accorded with the Langmuir model, while the Pb(II) conformed better to the Freundlich isotherm model.

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Hydrazinolyzed cellulose-g-polymethyl acrylate as adsorbent for efficient removal of Cd(II) and Pb(II) ions from aqueous solution

Water Science & Technology ◽

10.2166/wst.2016.581 ◽

2016 ◽

Vol 75 (5) ◽

pp. 1051-1058 ◽

Cited By ~ 5

Author(s):

Qiujin Jia ◽

Wanting Zhang ◽

Dongping Li ◽

Yulong Liu ◽

Yuju Che ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Physical Adsorption ◽

Freundlich Isotherm ◽

Isotherm Model ◽

Initial Ph ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Adsorption Desorption ◽

Efficient Adsorbent

Hydrazinolyzed cellulose-graft-polymethyl acrylate (Cell-g-PMA-HZ), an efficient adsorbent for removal of Cd(II) and Pb(II) from aqueous solution, has been prepared by ceric salt-initiated graft polymerization of methyl acrylate from microcrystalline cellulose surface and subsequent hydrazinolysis. The influences of initial pH, contact time, and temperature on adsorption capacity of Cell-g-PMA-HZ as well as adsorption equilibrium, kinetic and thermodynamic properties were examined in detail. As for Cd(II) adsorption, kinetic adsorption can be explained by pseudo-second-order, while adsorption isotherm fits well with Langmuir isotherm model, from which maximum equilibrium adsorption capacity can be derived as 235.85 mg g−1 at 28 °C. Further thermodynamic investigation indicated that adsorption of Cd(II) by adsorbent Cell-g-PMA-HZ is endothermic and spontaneous under studied conditions. On the other hand, isotherm of Pb(II) adsorption fits well with Freundlich isotherm model and is more likely to be a physical-adsorption-dominated process. Consecutive adsorption–desorption experiments showed that Cell-g-PMA-HZ is reusable with satisfactory adsorption capacity.

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